How to choose between 10 speed vs 12 speed drivetrain on mountain bike. Pros and Cons I'm buying a mountain bike from a company that lets you choose the drivetrain. I am having trouble deciding whether to go for a 1 x 10 speed Deore option (11-42) or a 1 x 12 speed SLX (recently released) (10-51) or GX Eagle Sram (10-50) option.  My budget could stretch to the more expensive 12 speed options. But is it worth it? Can't seem to find a definitive answer and cut through all the marketing. What are the  pros and and cons of 10 speed vs 12 speed drivetrain on mountain bike?

Some obvious benefits of the 12 speed:

Range

Negatives (correct me if I'm wrong):

Less distance between shifts?
Alignment very important for smooth shifting.
More expensive.
Quicker to wear out?

Previous drivetrains I have tried:

Traditional mtb 9 speed with triple front ring
1 x 10 and 44 tooth front chainring on my commuter bike
2 x ? on my road bike
GX 11 speed when I demoed the mtb I'm looking at
singlespeed huret flip flop
8 speed XTR.
fixed gear
mountain bike fixed gear
7 speed SIS
7 speed gripshit
Sturmey Archer 3 speed Chopper

It comes down to what you would enjoy more - how you prefer to ride vs cost.

I can't find any durability tests I trust but from my reading the general impression I get is that 10 speeds is no more or less durable than 12.

You have ridden many different drivetrains so you have built up experience that should guide your preference. 2 extra speeds in the shifting range is nice, is it nice enough to justify the cost? Only you can make that call.


Bottom headset cup doesn't sit flush After a crash, I noticed my bottom headset cup was no longer sitting flush with the frame (see the right side of the image below). If I grab the headset cup I can rock it back and forth slightly. No cracks I can find at all.

Is it possible to repair this and get the headset cup to sit flush/tight again or is the frame ruined?

The frame tube around the cup may have been 'ovalized'. The fork can exert considerable leverage on the bottom of the head tube.

The bearing cup needs to be pulled out and the frome inspected. Specifically you need to check if the tube recess for the cup is still round. This can be done with a good set of digital calipers by taking inside diameter measurements at right angles to each other.


Right hook accident scenario: who is at fault? I just got into a collision with a biker while driving my car. I have read a lot about these types of accidents, but none quite cover the circumstances that were present in my case and I’m wondering who is at fault.

I was stopped at a red light in a line of cars. I was probably the 5th car in a line of 8. The intersection was at the bottom of a hill on a one-lane road with a bike lane on the right side. I had my turn signal on at the red light and when it turned green and I got to the intersection I turned right. As I began my turn, I collided with a biker who was going much faster than me but approaching from behind, and was trying to go straight through the intersection.

The short version is that I was trying to turn right in a line of cars when the biker who was behind me struck the side of my car as I was beginning my turn.

Luckily the biker wasn’t hurt because I wasn’t moving very fast and he just clipped the edge of my car instead of actually hitting the side. He just had a few scrapes, thank God.

I don’t know what to think in this situation because I was in the rightmost lane with my turn signal on, in front of the biker but, on the other hand, it makes sense that he wouldn’t be able to see my blinker very well because of the line of cars and I could have seen him if I looked in my side mirror.

EDIT:  I can't believe this has gotten so many responses.  Thank you all for your thoughts.  A few people have been asking about where this happened.  It happened in California, USA.  A lot of people here are saying that they are thankful that things didn't turn out so bad, at least not nearly as bad as they could have.  I completely agree.  When I was helping the biker up, he said "That's the last time I come flying down that hill" and I responded with, "That's the last time I turn without checking my side mirrors".  So hopefully we, and anyone else reading this, can at least be thankful that it was a learning experience and that we can all be safer in the future.

One more thing.  Because the light had recently turned from red to green and I was in a line of cars, there seemingly was no way for the biker to safely go behind me and pass on my left, as there were a few other cars behind me.

Also, thank you Rider_X for the awesome and comprehensive response.  I come from an area where there are no bike lanes so I didn't realize that you are supposed to move into the bike lane before turning.

You will likely be found at fault. Bicycle lanes are considered a lane of traffic that supports only one type of traffic for extended periods of time (i.e., bicycles). As such, by your description you signaled your intent, then turned right across another lane of traffic and collided with another vehicle  already occupying that lane. It is your job to ensure a lane of traffic is clear before entering it.

If you were talking about two car lanes I think there would little if any questions regarding fault, but because we are talking about cycling many motorists assume it is the job of the cyclist to get out of the way because they are more vulnerable. While true from a practical perspective, this perspective is not supported legally.

Further confusing matters, in some areas  (e.g., North America) drivers are required to merge over into the bike lane (when safe) before turning, while other areas of the world do not allow any merging and instead give the cyclists the full priority at all times. Regardless, both approaches would find legal fault with the motorist turning across another vehicle lane (i.e., the cycling lane) when it was not clear to do so.

So what should you have done (North America)?

Generally in most North American jurisdictions if the bicycle lane is clear you should first merge over into that lane before making a right turn (see diagram below). This merge area is often indicated with dashed lines separating the car and bicycle lanes. If you safely merge over, then you have physical position over the cyclist and they should wait until you complete your turn before passing if they wish to remain in the bicycle lane, otherwise they will need to change lane into the main traffic lane to the left to pass (assuming of course a jurisdiction that drives on the right).

While you had your signal on you were still in the lane to the left of the cycling lane (i.e., left of another vehicle lane) and as such you had only signaled your intent. Until you safely enter the cycling lane, to complete your right turn, it is expectant upon you to check for traffic before moving to the right.

From San Fransisco Bicycle Coalition

Other North American Jurisdictions supporting this approach

I chose the figure above because it clearly communicated the concept. Some might be concerned that this only applies to San Francisco, but similar rules apply in many other North American regions. Some further examples are given below:

Ontario, Canada

  Diagram 2-12

  Bike lanes are reserved for cyclists. They are typically marked by a solid white line. Sometimes you will need to enter or cross a bike lane to turn right at a corner or driveway. (See Diagram 2-12) Take extra care when you do this. Enter the bike lane only after ensuring that you can do so safely, and then make the turn.

  -The Official Ministry of Transportation (MTO) Driver's Handbook

British Columbia, Canada

  Where there is a broken line marking the cycle lane at the approach to the intersection the driver may move over to the curb into the cycle lane prior to making the right turn in the way that most people are used to. Drivers doing so are making a lane change and must yield to cycle traffic in the bicycle lane before moving over! In this situation, the cyclist must wait behind the vehicle until after the turn is made to clear the cycle lane.

  -DriveSmart BC

California, USA

  21717.Whenever it is necessary for the driver of a motor vehicle to cross a bicycle lane that is adjacent to his lane of travel to make a turn, the driver shall drive the motor vehicle into the bicycle lane prior to making the turn and shall make the turn pursuant to Section 22100.

  California Law

European Jurisdictions

European jurisdictions give bicycle lanes legal vehicle status, but what seems less clear is if there is support for motor vehicles merging across bicycle lanes before a right turn (if driving on the right). From the comments it appears most European nations give cyclists the absolute priority (i.e., the driver needs to wait until there is no cycling lane traffic before turning).  Explicit examples are still needed.

Germany (by sleske)

In Germany, you would be at fault (probably fully). If you make a turn (no matter whether right or left), the traffic behind you in other lanes has priority, and you must make sure you do not obstruct or endanger it before turning.

This is based on §9 Straßenverkehrsordnung (German traffic code):

  Abbiegen, Wenden und Rückwärtsfahren [...]
  Vor dem Einordnen und nochmals vor dem Abbiegen ist auf den
  nachfolgenden Verkehr zu achten; vor dem Abbiegen ist es dann nicht
  nötig, wenn eine Gefährdung nachfolgenden Verkehrs ausgeschlossen ist.

Translation (mine, no guarantees):

  Turning and reversing [...] Before changing lanes and again before turning,
  drivers must look out for following traffic; this is not necessary before turning
  if a danger to following traffic is not possible.

Southwestern Pacific

New Zealand (left hand traffic)

In New Zealand cyclists appear to have absolute priority as turning motorists are not allowed to merge across the bike lane to make a turn and are required to wait until the bike lane is clear:

  When there’s a cycle lane at a set of lights, you must not wait in it for the light to turn green, and you must not drive in it as you approach the lights (unless you’re riding a bicycle). Motorbikes must not use this lane, either, but they can filter between stationary traffic.

  Cycles have the right-of-way in this lane. If there are cycles waiting to go forward, you must give way to them before you can turn left.

  The car is waiting in the wrong position, blocking the cycleway

  This shows the correct position with the left-hand wheels of the car not encroaching into the cycle lane

  -Driving Tests NZ


Regaining frame aligment I bought a belt driven bike which had had the rear triangle of the frame moderately bent (i.e. bent but no tubes collapsed or cracked) – it was a gamble as to whether it’s fixable….  It has a Nuvinci 330 hub with disc brakes which requires a large 135mm dropout spacing.

The frame is made of steel and I’ve been able to bend it to near alignment.  However, as I don’t have a reference bike to compare measurements from, I’m struggling to figure out whether I’ve aligned it properly or not.

Firstly I aligned it based on the string test (Sheldon web page and also a Youtube video) so that the distance between the string and the seat tube frame member was equal both sides.  I got this right to within 1mm and was happy with myself.

But then I dropped in the rear hub and tried to pedal it.  It turned but it was making a noise which wasn’t very happy and you could tell the hub wasn’t aligned with the pedal wheel, with the belt rubbing as it seated itself on the gearwheels.

So then I bent the frame some more and now turning the pedals works really well and looks like it’s all fitting nicely, however if I do the string test there’s around a 6mm difference in the distance between the string and the frame between the two sides.  However if I measure distance from each rear axle end to the same point on the headset it’s the same distance within measurement error, so I think the axle is sitting perpendicularly to the line of the frame.

So the question is this.   Does all of the above mean my frame is bent in some way where I just won’t be able to fix it?  The bottom bracket is one of those split types so that you can tension the belt – it looks horrifically weak structurally to my eye and it may well be that the bottom bracket axis is no longer perpendicular to the frame plane which I doubt I could fix.  Or maybe a 6mm difference in the string test is not enough to worry about?  Or are some frames deliberately made so that the string test should not return the same measurement which would mean that the way I have it now is perfect?

Thanks in advance for any help.

PS.  I am waiting for a rim before I can restring the rear wheel and this is taking a while to arrive – hence I’ve not been able to ride it to see how it feels.

A couple things here that could be tripping you up:

Both belt drive and Nuvinci hubs can be noisy all by themselves. Belts frequently also make noise in the stand that vanishes when riding and vice versa. Getting belt tension just right is a whole other step and noise will frequently be the result when it's not dialed. Lubricating it is another piece. (I always use silicone cleaning spray, and yes this is a Gates-sanctioned thing). If the rear cog was visibly out of line with the front, then perhaps this isn't likely to be the problem, but worth mentioning.
When you bent the frame around the second time and the noise went away, it could have affected the belt tension.
If somehow the chainline (beltline) was incorrect with the parts that are on there, it could create the situation where it made noise when the alignment was right and didn't when it was wrong.
Doing what you're attempting without dropout alignment tools or an improvised substitute is iffy. What they do is integral to the whole process of aligning a frame after it's been severely misaligned.

You mention that you're seeing some torsional misalignment between the BB and the front wheel. A way you could go about trying to fix that is taking the fork out, clamping the BB in a vise with some old steel cups, removing the fork and headset, and getting a long steel pipe that mates closely with the inside of the head tube to use as a leverage bar. Then to check the alignment (which you should do first) you can hold the frame up against a light source and eyeball the parallelism between the seatube and headtube. This isn't likely to have any bearing on rear torsional alignment though. You need dropout tools for that.

Something you can do is take a long, straight piece of square aluminum extrusion, like 80/20, and use it as a straight edge referenced off the bottm bracket. For example, clamping them together in a vise, measuring with a caliper between the seat and the straight edge all the way down their lengths, repeating for the down tube, then removing the straight edge, re-clamping the bb, and reefing on the tubes. If there is shell misalignment, something like this is how you'd fix it.


Rear gear change misses 1 gear Hi I have a 9 speed setup with the derailleur that springs to the largest cog.

My problem is that when I change through the gears one at time it misses 1 whole gear in the middle. It doesn't sit and "chatter" trying to change, it just jumps over 1. When I get to the smallest I still have one more shift on the shifter.

I am reasonably experienced at getting gears indexed and can normally get them right but this is driving me mad. the low screw is set just right and their is no slack on the cable when in the low gear. It changes fine the first 2/3 gears then misses one and carries on fine to the highest the same in reverse.
any ideas?

Thanks

Hard to say exactly what is going on but I suspect the problem is in the cables and housing - either a routing problem or the cable is sticking.

Inspect the cable run and ensure there are no kinks and the housing is inserted in frame bosses properly.

Pull the cable out and clean it, lubricate and re-install (can be hard of the tip of the cable is frayed). Even better, replace cable and housing which is relatively inexpensive.

Re-adjust the derailleur. Start by rechecking the high and low limits. Start the indexing on the smallest sprocket - that way you know you won't have the problem of the derailleur arriving on the smallest sprocket with on click to go.


Disc of front brake rubs under force I ride a road bike with carbon frame and fork an hydraulic flat mount disc brakes. A fews days ago the front disc was slightly rubbing on the braking pad, so I readjusted the position of the braking saddle (loosen mounting scews, pull brake, thighten screws back accordingly to producer manual Nm). This worked fine and the rub is gone and hasn't come back.
However, when I put force on the handlebars - and thus the fork - like pulling handlebars when restart after red light stop or when ridding out of the saddle, there is a slight rub when applying force. It immediatly stops rubbing when ridding "normal".
So should I be concernd about this/reajust the brakes? Or is this just the fork flexing under pressure and nothing to worry about?

Flex causes this and it's not going to hurt anything. However, it's frequently the case flex is just the contributing factor that pushes the system into rubbing.

Look down at the gap between your rotor and pads, and slowly spin the wheel. If you were to see consistent .2-.4mm-ish gap on both sides, a true rotor (no warbles), and good parallelism between the pad and rotor, there's not really anything you could do to improve things at that point, and you'd know it was just flex causing the rub.

If you see an out of true rotor, off-center pads, or very minimal gap all around, then that means the rotor is getting closer to the pads in certain spots than it should be able to, and while it may not rub unloaded (in the stand etc), adding flex is getting it there. So to solve it you may need to true the rotor, face the frame/fork, reset the pistons, and/or adjust the caliper position.


How to Reattach Cable End for Road Drop Bar Brake Lever I was installing new brakes and I pulled too hard on the lever and the cable end disconnected from the brake lever. I'm having trouble reattaching it because it can only be pulled out so far due to the cable housing and it's such a small space. Is there a specific tool i need to use because this happened to me once before and the guy at the bike shop fixed it without removing the housing. I don't want to keep going back to a bike shop every time this happens so I need to know how to do it on my own if I am out on a ride.

Going out on a guess for anyone who might stumble on this. it sounds like he grabbed the brake lever and pulled tight, perhaps checking for brake pad alignment, spacing, etc. The cable pulled loose from the brake caliper (not lever) and disappeared into the cable housing. If so, grab a zip tie (or a shoe lace) and pull said lever all the way back to the handebar. Secure it to the handlebar by zip tie, shoe lace, whatever. Grab a flashlight and shine it into the innards. You'll see the cable end coming out of the internal guts of the lever. Take a flathead screwdriver or needle nose pliers and push the head slowly back into the lever until it stops. Check the end of the cable housing by the brake caliper and you should see the cut end sticking out. hold on to it and release the brake lever from the handlebar. That should do it.


What did people ride for cold weather cycling "back in the day?" (Is it cheap?) Everyone who has ridden a bike any real distance in the cold has likely noticed a few things.  Due to the speed to effort ratio of the bicycle, certain thermal realities have different relationships than they do on foot.

For example; a cyclist who is going up a hill can easily become hot and sweaty in clothing that would not sufficiently protect a sedentary person from the cold.  If, however, they were to go down a hill shortly thereafter, they might find themselves facing an improbable gust of wind... with increasingly wet clothing from the prior effort.

To say nothing of if such a poorly protected cyclist were to start by coasting downhill in clothing insufficient to... either way welcome to my commute.

Now, there seems to be a vast array of, well, fiber technology meant to protect someone in just this scenario.  I found that even wearing a $10 jogging undershirt made a huge difference over cotton.  ("Cotton kills" as the boy scouts say.)

But that segue into my question: what exactly were people doing BEFORE spandex (aka lycra) and other synthetic fibers?

If you believe the industry, you'd think you HAVE to have the more advanced stuff, but I doubt that people just stopped riding in the winter before it was invented... or did they?

(And can I avoid buying any kit by imitating them?)

Wool, wool, and wool. Wool undergarments. Wool over garments. (Maybe tweed as well.) Wool is a amazing material. It tends to perform better than synthetics (although the gap is closing) for keeping you warm when it is wet and cold outside.

On descents people also used to just either tough it out or did life hacks such as putting newspaper down the front of the jersey rather than rely on fancy rain shells.

Now here is the caveat about wool and the old world approach. Real wool garments are often much more expensive than equivalent synthetic garments. So from this perspective synthetics are a much better choice than killer cotton if you cannot afford wool. Synthetics also tend to wear a bit harder and typically don't need to be hand washed, so wool is more care. You typically only had a few garments which you washed by hand at night before the next day of riding. You also had to learn how to darn wool, so you could fix damage that can happen to wool over time.

Synthetics dominate today because of the cost, reduced care and good enough performance.


How can I tell what frame model/year this bicycle is? There is a bicycle that is locally owned that I want to buy and the only information I have about the bicycle frame from the dealer is that it's just a OCLV 110. With a couple of zoom-ins and research, I think this is Trek 2002 5900 USPS bike, is this correct?This is the picture

Bikepedia is a good resource for indentifying models, year and spec levels.


Can i set up a 7speed gear and disc brake on hercules rocky mtb 2.0 cycle My cycle is a non gear cycle .Can i set up disc brake and 7speed gear.

[![ this is my cycle ][2]][2]

In short, no.

There are two main problems:

Your bike does not have disc brake tabs.
Your bike does not have a derailleur hanger.

To be fair, it could be done, it would just be so expensive that you'd be better off buying a completely new bike with gears and disc brakes. If you chose to pursue this project, you would need:

a new fork with disc brake tabs (with the type of fork you have, this might actually be pretty hard to find)
some sort of disc brake conversion kit for the rear (I know that these have been made in the past, but they may be hard to find now. I'm also not sure that I, personally, would trust something as important as braking to a conversion kit.)
A new set of wheels with disc compatible hubs and an internally geared rear hub.
disc brake rotors
disc brake calipers
A gear shifter that's compatible with whatever internally geared hub you decide to buy
a derailleur cable
new brake cables

And I'm sure it goes without saying that you'll need some tools and a good book about bicycle maintenance.

I think that covers it. You're probably looking at $500 (US) minimum, probably more like $1000.

For that price, just buy a new bike that has discs and gears.


Multiplication of Cassette Ratios The title can not explain it more specifically, however, recently I watched a video where I guy explains a calculation and tells the result gives how easily you climb ramps. Here is the calculation:

Rear cassette: Biggest sprocket size / smallest sprocket size
Crank cassette: Biggest sprocket size / smallest sprocket size

You multiply the end results and multiply it again with 100 which gives you a percentage.

Here is an example:

Say I have a front cassette 22-32-44 and a rear cassette 11-36. The calculation is as follows:

(44/22)*(36/11)*100 = %654

So the guy says the bigger this number, the easier you climb ramps? That doesn't make ay sense to me. Does it hold any truth or does he try to mean something else?

As others have already noted, the figure to which you refer pertains to the drivetrain's range, not to the lowest gear. The mechanical advantage that allows you to climb hills easily (small chainring driving your largest cassette's sprocket, say 22x36 in your example) is customarily expressed in gear-inches, a rather meaningless measure -- it indicates the equivalent diameter of a wheel that would be geared 1/1, but a standard nonetheless. 16 gear-inches would be considered small. Your example yields 15.9 gear-inches.

An excellent gear calculator can be found here. Play with it and all should become clear.


Maillard Freewheel refurbishing I have a Maillard freewheel, big cog stamped 10 - 84, which i have taken apart, cleaned, lubed, and reassembled following the excellent youtube by RJ the bike guy

            .

i don't know for certain, but i may have "misplaced" the spacers which slide down the body and allow the pin spanner locknut from crushing the bearings. the freewheel is back together, but i cannot tighten the locknut and still have the cogs rotate.

Q; how far up the river am i, and what can i do to get new spacers/ what size?

thanks

this week should be the litmus test. i had to order a freewheel removal tool (Maillard 40 mm x 24 notch if memory serves) and i have found 2 companies* that might have the parts i need. i've had to put it down for a couple of days and take a deep breath. i'll regroup and go at it again when the remover arrives.

Bike Tools Etc. &
Loose Screws Bicycle Small Parts


Is my saddle at the correct position? I am trying to determine if my saddle is setup right.

In the picture below, my feet is at 9 o'clock and the improvised plum line that starts under my knee cap (hard to see, spot the white line against the bottom tube) is not going through the ball of my foot or near the pedal.

IIRC, the line should go through the ball of my foot and pedal spindle right? In this case, I need to back up my seat?

Edit #1

In the hopes of adding and clearing this post up a little, here's the other screenshot that I had taken with my heel on the pedal, to show the height component of my saddle:

I thought the height was ok.

I'm trying to solve an issue and wanted to tackle each bit individually starting with my saddle setup.

The issue that I'm trying to solve crops up after some time on the bike. It seems to be related to the amount of cranking going up hills. It varies in time and distance. If I concentrate on being in a lower gear than I want, and patiently go up hills, I can delay the pain from appearing.

The pain will start on the back and outer side of the knee, at the very top of the right calf. It first starts off with a warning, a dull pain. Then, I need to push the bike up the hill due to the pain when I crank on the bike. I can do flats and downhills ok.

IIRC, this is entirely related to my cleat positioning.

So far, I have been moving the seat around a bit to test to see if it made any difference. It doesn't. This post was to take the seat out of the equation so that I can move on to other things.

Edit #2

For the sake of completeness, I'm adding new snaps featuring more legs :)

Edit #3

IMO, it seems highly likely a cleat issue. However, wondering out loud, could my issue be related to lack of mobility perhaps due to some muscle groups not firing properly? (Glutes maybe?)

Not enough information can be seen in your picture.

What you are looking for currently is a red herring. Whether a line from your knee cap does or does not cross any point on the shoe or on the pedal is strongly affected by the seat tube angle (and also the crank length). In the extreme case of a recumbent bike there is no way those could intersect - but the position setup is no less important there.

And not just the (for some to far-fetched) recumbent bike example, check this racer

(from https://www.slowtwitch.com/Photos/Products/Winners_and_Losers_Helmets_4712.html)

Due to his seat-tube angle the guy cannot ever fulfil the rule.

What you should look for are the smallest and the greatest angle your knee makes. For that you need the pictures of you pedalling made from higher point, best completely perpendicular to the knee. That's what bike fitters are looking for (among other stuff). A bike fitter can do that for you or you can try to do that yourself, there are instructions available on the internet (e.g., https://www.ludd.ltu.se/~torger/bikefit/ - the site also discusses the KOPS method you have used, for most common bikes and average riders it works quite well but the site does also offer better methods).

(from https://www.ludd.ltu.se/~torger/bikefit/)

To answer your actual question about your own position, taking your edit into account: I cannot see any obvious problem in your seat height and I would indeed try to search a problem in the cleat position. You can also try flat pedals for a while and check whether they change your situations. The may help to narrow down the problem. It is less easy to assess your forward-back seat position but considering the KOPS method it is not way off but may be slighly forward. Or it may not, I would still try to measure your min and max knee angles, it is more accurate and considers the actual piece of your body that hurts.

Ad Edit 3: It can and it can be due to many various gate issues. For example, I have problems with my hip and knee orientation and resulting duck feet which is worse on the right leg. Some issues are more obvious and some less. A professional eye will know better (a physiotherapist or bike fitter, but not just any, but some that actively deal with similar problems). Consider cleats that allow some float and try to find out what Q-factor may be the right one for you.


Is cycling on this 35mph road too dangerous? I'm thinking of bike commuting to work and there is a stretch of road with no sidewalk and 35mph speed limit.  Is this too dangerous for biking?  I'm not in the best shape so I can't go very fast. This is Hawaii in the United States.

As an experienced cyclist who has been all over the country and even done hundreds of miles on interstates, after finding that location on Google Maps, and checking  how you might conceivably get there, there is absolutely no way in hell I would ever be caught dead there on a bicycle.
How you answer this question is not by taking one isolated photo out of context, but by looking at the totality of how you would get into and out of the location on your bicycle. By doing this, we can quickly see that it would be unwise to use this road, and a serviceable (and far safer) bike path alternative exists.
There are two ways to get there: The first is to exit H-1; your picture was taken where that off-ramp merges with Nimitz Hwy. I won't discuss this further as it would be illegal to cycle there anyway.
The second is to enter Nimitz Hwy from Kamehameha Hwy at Middle St here:

That means you would have to ride in one of the two left lanes, likely in the middle of heavy traffic, from at least there until you merge with H-1 later on up the ramp:

You would be cycling in the lane where this picture was taken, and would then have to cross those two lanes to the right which are full of cars coming off H-1. This is extremely unsafe unless there is virtually no traffic. I might do it at four in the morning. I would not go anywhere near it in normal waking hours.
Fortunately you don't have to. Just to the right is a bike path which runs parallel to this bit of Nimitz Hwy, ending at Peltier Ave. The sidewalk on the right turns into the bike path just after Middle St:

Instead of trying to play Frogger with high speed vehicles up above, I'd use this bike path.
Given that it's pretty much impossible to get to the point in your picture safely, I've omitted the analysis of how to get out safely.


Truing stands, go big or stay home? I'm looking to buy a truing stand. Is the Park TS-8 Home good enough? Or should I pay double the price and get the Park TS-2.2 Pro. I have some experience truing wheels, but never on a nice stand. I was using my makeshift home made stand which consists of an old fork and calipers constructed from u-brakes that are bolted on to the fork.  Obviously anything would be huge step up from my current method, but I wonder if the Pro is really that much better?

I only need to true bmx wheels (20in) and I used to run 48 spokes so they would stay true for a long time. However, I recently switched to 36 spokes and I find they need a lot more attention.

The TS-2 is what I use and I quite like it.

3 of them are 17 years old and we just purchased a brand new one. Of course everyone likes the older ones ... hah.

Anyways, in my opinion you do not NEED to buy the more expensive one. If you are truing 10+ wheels a day, yes you need it (in my opinion). For home mechanic work, the TS-8 is just fine.


Hydraulic disc brake - lever compatibility I purchased a gravel bike with drop handlebars, mostly for commuting and maybe for some weekend bike camping trips.  I've only ever ridden mountain bikes with flat bars in the past, but I figured I'd get used to the drop bars.  After a month I'm realizing that drop bars are just not for me.  So I want to take my Jones Loop off of my MTB and put it on the new gravel bike.

The gravel bike had Micro Shift MTB bar end shifters so I picked up the matching flat bar adaptors for $40 and that will be a real easy 10 minute switch.  Now I just need brake levers but I can't seem to find definitive answers online about which ones will be compatible with my brakes.

I've never bled a brake line before but I'm confident that I could do it and its only another $20 for the line bleeding kit.  More than one blog says that there are not many compatibility issues with hydraulic levers when switching from drop bar to flat, but I can't find anything that says if I can just use any random hydraulic levers with these brakes.

The brakes on the bike are TRP Hylex hydraulic disc brakes.  From what I can tell, TRP only makes one flat bar hydraulic disc brake set and they don't seem to sell replacement levers.

I don't need top of the line parts, but I don't want to buy something that is going to break easily.  I found a store selling what look like very basic levers, Shimano BL-MT200, at $15 for the set.  I also found a list of other Shimano levers at varying price points, BL-M6000, BL-M7100, and BL-M8000.

My questions are:

Can I just swap out the TRP Hylex drop bar levers for these cheap Shimano levers?
Could I hypothetically use just about any random hydraulic levers? SRAM / Tektro / Shimano
Does it make good sense (would I notice a difference) to buy a more expensive lever like the BL-M8000?

An important reason why you can't randomly mix and match hydraulic brake parts is because different manufacturers use different hydraulic fluids. SRAM uses DOT 5.1 brake fluid. Shimano uses mineral oil. Campagnolo uses mineral oil. Using the wrong kind of fluid can damage the seals.


White foam around tubeless tires I've bought this bike new about 10 months ago. No issues until now, only the fact that my tires (tubeless) lately have constant white foam like this:

Now I have to pump up my tires every day before I ride, but the bike is still usable through the day even for long rides.

Now I know that I should take it to a shop, but I want to know what to expect there, would it be a difficult and expensive job?

Thanks!

Modern tubeless bicycle tires require a sealant to be added to the inside of the tire. If a small leak develops the sealant seeps out, meets air, solidifies and seals the leak. I believe this arrangement has become popular because earlier tubeless standards like UST required heavier tires.

The white foam dots you see is the tubeless tire sealant leaking out of holes in the sidewalls of the tire, and failing to seal them completely it seems.

what's fascinating is the pattern of holes in the sidewall, I've never seen anything like that before. I think commenters on on your question are correct, there's possibility you have damaged the sidewall by riding with excessively low pressure which has folded the sidewalls at an acute angle.

Refreshed sealant may solve the problem - sealant loses effectiveness over time. Replacing sealant or a tire is not difficult and is relatively inexpensive, depending on the the replacement tire you choose.

Have the bike repair shop check the tire for damage, if the tire is obviously damaged or even suspect I'd opt to replace it as the labor cost for replacing the tire with new sealant will be the same as replacing sealant in the existing tire.

While you are at the bike repair shop, have the rear wheel checked for trueness , you may have suffered some impacts with the tire under-inflated. Also, think about getting yourself a pump with a pressure gauge to avoid future problems if you have been under-inflating the tire.


What is the difference between cheap and less cheap road bikes? I am new to road biking. I have ridden mountain bike in school and have been away from biking for about 5 years now. Looking around online tells me that three categories (in terms of price):

Some real cheap ones, for example Vilano Aluminum Road Bike 21 Speed Shimano for $329.00 - $379.00
Medium range ones around $800, for example Diamondback 2013 Podium 3 Road Bike with 700c Wheels
And then very expensive ones.

I am planning to buy it for casual use (not for high speed). I would probably go ride in evenings for about 25 miles. Can somebody please suggest the differences in first two categories?

There are many causes for price difference in bikes. There are others reasons than these listed below, but they tend to fall in line with one of these four categories.

Brand

Branding is always a premium. As in every industry I can think of, some brands have a reputation that to some extent justifies a premium price. This reputation is based off a multitude of sub factors, such as warranties, customer care, recognized build quality, athlete association and such. Top brands such as Trek, Giant, Bianchi, etc. have built up a reputation over the years of their existence that people deem worthy of a premium price.

Materials

Materials used in the frame (and also components, but more on that later) affect the characteristics of the bike, but due to the nature of high-tech processes, these come at a price. For instance, high-modulus carbon fiber performs better than cheaper carbon types. The pricier stuff is lighter, stiffer, stronger, more durable or some combination of the above. Likewise, carbon has superior performance properties compared to aluminium or lower still, steel. Within the scope of any one material (carbon, aluminium or steel) there are many sub-classes that will perform better or worse - and have a price to match. The two bikes listed exemplify this point - both are made from aluminium, but the more expensive bike is made from a higher grade (7005 as opposed to 6061). The more expensive option also has a carbon fork - an expensive but potentially worthwhile investment.

Components

Bikes most commonly come as complete units, with only super high-end models available as frame only builds. This means your money is covering all the components on the bike as well as the frame. Components make a big difference to the bike's performance, from weight or strength to durability or aesthetics. The componentry of your bike directly influences the way you use it. For instance, clipless pedals (such as Shimano's SPD system) determine the way you pedal. The bike listed have some important differences in componentry:

The cheaper of the two has gear shifters separate to the brake levers. This is common on cheap road bikes, but in my opinion is incredibly annoying. Purists may argue that old bikes were made this way, but honestly, I find them almost dangerous due to the necessity for hand position changes every time you go to change gear or brake. Perhaps just a personal opinion, but worth considering.

The other big component difference is the gruppo - the drive-train, gears, etc. On the dearer model we have a FSA Omega compact BB30 Crankset. While not the top of the line, I would assume that this particular set would be more reliable or better built that the otherwise unnamed model from the cheaper option.

Finally, before we get bored of details, the wheels are an important component to consider. More expensive options are sometimes made from carbon, but stepping down from the elite we still see performance features such as flattened spokes or radial spoke arrangements. The Equation R's on the Diamondback have radial spoke lacing, but the Vilano does not.

Customization

In the realms of the super elite, performance gains become harder to achieve, and the associated cost increases drastically. There appears to be some sort of law of diminishing returns at play - the price difference between a 20kg bike and a 19kg one may be $200, while it could well cost you $2000 to save a couple of grams of paint (not kidding - check out Trek's Project One customization site, specifically the 5gm Vapor Coat Paint. That's pricey!). Essentially, we reach a point in the spectrum of bikes that performance is so good, that other factors such as custom paint or gram savings through carbon brake levers and spacers become the only avenues for improvement. This uber-rich world of cycling is almost exclusively for the professionals and hence self-funds through sponsorships and such, but it is available for anyone lucky enough to have deep pockets and exorbitant taste!

So those are the main reasons for the price discrepancy. Hopefully that should educate your purchasing decision! Good luck!


Are granny gear chainrings supposed to have directed teeth (i.e., be non-flippable)? I was replacing a worn-out 34-teeth chainring on my MTB crankset. In the course of the work, I detached the granny gear chainring (22-teeth).

Compared to the big chainring, which has all these ramps and non-regular teeth shapes designed to facilitate gear change, the small ring is completely flat. It looked completely symmetric to me, apart from apparent slight wear on one side of teeth caused by chain contact.

After I'd given it some thought, I flipped the granny chainring over so that another side of teeth was used to contact the chain. This is a regular practice with single-speed chainrings which are symmetric, and it is used to double their useful life span.

However, after I'd put everything else together and adjusted it, I took it for a test ride. Immediately I uncovered that shifting up from granny gear to big gear was now accompanied with chainsuck, as the chain managed to "stick" to the small ring all the way around its circumference. It happened in about nine of ten shift attempts.

No amount of tuning of the front derailleur helped to solve this problem. Now I start thinking whether my judgement about the granny chainring was wrong, and it is asymmetric and cannot be flipped over.

Another possibility for chain suck that I can imagine is that the new big chainring is actually smaller — it has 32 teeth. It is also possible that I installed that new ring incorrectly (should have rotated it 90 degrees relative to bolt holes); but then again, I cannot see how it matters as the smallest ring has no ramps which could be aligned against the big ring.

So what should I do? Flip the granny gear back, look for a bigger chainring, or rotate it?

The crankset is Truvativ X5, 22/34t. The derailleur is SRAM X5.

I think @Chris H is most likely correct, the ring is probably not symmetrical.

Other possibilities are that you did not install it quite correctly, or that there are raised burrs caused bu wear that are hanging on to the chain.

If you really want to find out if you can reverse the ring, install it the 'correct' way around, get shifting working, then reverse it again. That way you know that shifting setup is not causing the problem.


What bike is this? Need to find derailleur hanger I know derailleur hangers are specific to their frames, and since there are numerous brands with numerous models, I would need to know which one mine is before I can start searching for it, right?

What I know about the bike:

Brand: Giant
Model: Boulder
Frame: Size L, 6061 ALUXX Butted Aluminum

What I need to know:

The year this one was brought to market
Info on how to search for a derailleur/mech hanger (I fiugre the above will be relevant to that)

I have found this, but how can I be sure it's the right one?

Any help would be much appreciated!

It looks like you need this one (Wheels Mfg 21, which they list for Giant Boulders of all years).

If you took the bike to your bike shop, they'd compare the derailleur hanger visually to other ones used by Giant and see there is nothing else like it. Or pull up a chart from Wheels Mfg and look up what bike it is and which ones could fit.

So it looks like the one you have found on eBay is the right one.


Can you have an Ultegra crank arm on the one side and a 105 crank arm on the other side I have an Ultegra groupset, but I also have a 105 left crank that has a power meter. Can you mix these two? I don't care about the weight difference, only talking about a geometry point of view. My left shoe and right shoe's cleats are in exactly the same position, but my left side shoe (at the contact point of cleat and shoe) is against the crank arm?

Yes, 105 and Ultegra components are largely compatible but it depends on the exact model numbers. Its best to check Shimano's compatibility charts.

I myself have a 105 crank on the left and an Ultegra on the right as the bump in my left Ultegra power meter crank won't clear my chainstay. They're both Hollow Tech II which means they're compatible.


Bike computer that logs all data to smartphone Is there a cycling computer that logs all data on your bike and can output that data to a smartphone in a meaningful way?

The issue with something like a Garmin Edge and Strava is the notion of "workouts". Besides times I'm actually working out, I ride my bike everywhere, and though a 1.5km ride to get groceries seems negligible, in a single day I can get 20km of these short rides in.

Ideally, something like a good old Cateye Velo 7, which logs as soon as movement is detected, but can sync all the data to my phone where I can see graphs and all the good things modern health apps provide.

Yes, but the SRM computer is designed (and priced at close to $800) with the professional athlete in mind. It is said to autostart.


Why does my chain have a single hollow pin? I have some version of a SunRace 10-speed chain, and I'm curious as to why it seems as though each pin is a regular "non-hollow" pin, and a single one on the chain is hollow.  Is this some kind of a master link?  I couldn't tell via - How can I tell if a chain has a master link?.

Its not a master link - that's probably the one-use pin that was used to close the chain the first time.

This is what a Shimano pin looks like after its been snapped off.   There's a clear difference to show this pin should not be pushed out again because the plate holes will be enlarged slightly.

Your one doesn't look quite the same - it does look like a snapped off line exists though.  This was probably a hollow connection pin rather than the solid one supplied with that chain, or perhaps sunrace pins are all hollow.


How to mount central (two-legged) kickstand on normal bike frame I bought this kickstand, but it has grooves in the top that the instructions said should slot into the "stand plate" on the frame.

My frame looks like this: doesn't seem to have a plate of any kind, and the chainstays don’t fit into the grooves on the kickstand.

So is this kickstand a weird one that needs some kind of plate, or are all centre kickstands like this?   If so, how do I fit one to my frame - can I buy a separate base plate?  This was the only thing I could find like that..

The groves are for any cables that are routed under the stays.
Your kickstand should have come with a counter plate - B in the picture below
Your kickstand is slightly different but the mounting instructions will be the same as the kickstand below
ergotec Double-leg kickstand Double Flex 3 manual

Bicycles without a stand plate

Check if the distance between the housing of the bottom bracket bearings
on the frame and the tyre of the rear wheel is sufficient for the assembly
operation.
Now you attach supporting surface C from below to the chain stay on the
frame. If there are cables here you press these into the notches D provided
for this purpose.
Adjust the double-leg kickstand in such a way that when folded into place
there is space of at least 15 mm between the kickstand and the tyre of the
rear wheel.
Now you place counter plate B on the chain stay from above and fasten it with clamping screw A.
Tighten clamping screw A to a tightening value of 21- 23 Nm.
Finally you check that the chain can move freely. For this purpose you should
engage all the gears once.


Chain length adjustment If I change my 1x chainring from a 44 to a 42, do I need to shorten the chain? If so by how many links?

I am running a 44 with an 11-42 cassette (SRAM Apex1).

You are reducing the minimum length of chain required by 1 link. (i.e. 22 teeth vs 21 teeth on the front chainring.)

Unless the initial chain sizing was overly generous, you should not notice any significant difference in that small a chainring size change. Since you can only remove 2 links, not just the one link you are changing, you are likely already in
the appropriate zone for chain length.


What type of brakes are best for mountain bike racing? Disc brakes are more expensive than v-brakes, but in a heavy rain they will break down. V-Brakes are becoming harder to find, but they're much easier to maintain and don't break down as easily.

What kind of brakes are best for mountain bike racing?

Look at any high end bike and you will find hydraulic disc brakes.

There will be people who argue the pros/cons of hydraulic vs mechanical disc brakes but it's hard to deny what the entire industry is putting on their most expensive rigs.

For ease of stoppage, minimal brake fade and ease of modulation - the hydraulic disc brake wins hands down.  You can hammer downhills w/ disc brakes all day long and your hands don't get tired... try that with old school cantis or v-brakes.

Plus - disc brakes will maintain stopping power in wet vs a rim brake which will definitely be compromised in wet.


Shimano clipless pedal screw loosening On my MTB I have Shimano M505 clipless pedals and one of the pedal bases has play. The screws that keep the front piece attached to the pedal base regularly loosen irrespective of how much I try to tighten them.
Any suggestions on how to fix the pedal?

In addition to the comments about using a blue thread locker (or red if you plan to never remove them), I would wonder if a different material of machine screw might have more friction in the threads as well.  Stainless steel may have had threads cut too smooth to provide enough grip.  Additionally, if it is a flathead or philips type screw head you will not be able to put much force on it, even with both hands turning a screwdriver.  Using a hex head or star head with a ratchet can get magnitudes more torque, just don't strip the threads.
PS:  I now realized with the idea that stripping the screw from overtightening could happen on a new screw could still apply to the old screw.  If you've really tightened it with all you've got its likely that the threads have been pulled out and your screws are now more like toothpicks.


Why doesn't my (battery-powered) light work in the cold? I've got a cheap LED lamp running on three AAA NiMH batteries which stops working when exposed to near-freezing temperatures; is there a likely reason for this?

The lamp has been dropped a number of times due to my incorrigible clumsiness and the batteries are a year or two old; could either of these factors play a role?

Batteries, especially most types of rechargeables don't work well in cold conditions. The chemical reaction that powers the electric voltage does needs some temperature to perform as intended. If you then have a consumer load that requires a bigger amount of power, they tend to drain rather quickly since they cannot set free much energy when cold.

You could try with newer batteries, maybe yours are already a bit exhausted or you can try ones that are based on a different cell type.


Is there any good software to track and compare rides using my own computer I like being able to see a record of my cycling in Strava, and compare rides with previous ones, see if I'm speed up or slowing down etc.

But I don't like the idea of a company creating a database of where millions of identified people go. It seems like a privacy problem.

Is there any good way to view a history of my cycling and calculate cumulative figures using my own computer rather than sending the data to someone else to analyse?

I can copy a GPX file record of each ride to my computer but I haven't seen anything that will let me view all the data together, rather than just one ride at a time.

I use IPbike for Android. It has strava upload in case you want it but also gives you files in sensible formats by sensible means. It's got sensor integration but I use it with only GPS. You can give it a good try before you buy.

The author is no stranger to this site; despite being almost a neighbour of mine according to play store, I've no connection (except for having eventually bought the software)


Is it possible to rebuild a a steel bike frame (to make it lighter) by welding aluminum tubes I have an old (80's I guess) road bike, it is heavy, I'd like to make lighter. is it posible to cut and replace the tubes on the frame by welding aluminum ones?

I would not.  Instead I'd strongly recommend you look at buying the bike you want rather than chopping up a working vintage bike.  At best you'll come out with something worse than a replacement aluminium road bike, and perhaps slightly better or worse than the bike with which you started.

A used 2000's bike would be a far better bike than some chopped-up monster, and then you have N+1.

Steel and aluminium are dissimilar metals and welding is not possible. You'd be looking at brazing them. If you expected to weld them, then perhaps this is beyond your welding skill level.

If you are paying someone commercially to do the welding, then they will braze or silver solder the work.  Check for what their workmanship guarantee is as well.

You will have to paint the whole frame properly afterwards too, the steel parts need protection.


Help altering old Marin MTB to an In-town pavement cruiser? I have an old Marin Bobcat Trail MTB with 26" wheels. I want to make a road bike out of it, and don't want to spend a bunch of money. I just want to be able to go fast and coast for awhile, so I don't have to crunch around on my Talus 29er.

I'm also ~230lbs and 6'6". I used to blow tires like crazy on that bike. Am I going to be struggling with that same issue with the tiny road tires??

I'd love to post pictures of the transformation. I just need pointers on how to RE-USE what I have on the bike, minus buying new a wheelset.

Thanks all!

There really isn't much required to make a MTB into a formidable city bike.

The obvious thing is to change tires. But I wouldn't actually recommend to go for something skinny just something not knobby. Skinny tires offer very little advantage but absorb a lot less of the bumps encountered in city driving which makes them less comfortable and put the wheels under more stress. Just find some nice (semi-)slick tires and you should be good to go (I just posted my preference in another answer and would feel like over-advertising if I mentioned my personally preferred make and model ;-)).

You may think about adding bar ends which offer an extra position for your hands which is quite comfortable on longer rides.

Most other things are personal preference or at least depend on how you're actually going to use the bike. Depending on your speeds you might want to look into larger chain rings for more top end and, since you're a tall guy, possibly longer crank arms.

Other things to think about: lights (hub dynamo vs battery), racks, mud guards, lock.


What wheels can I buy that fit this Shimano UG 5 speed freewheel? I am refurbishing an old 70s/80s bicycle, I have everything ready but the wheels, what set of wheels should I purchase that will fit this freewheel from Shimano?

A bicycle of that era will likely need 27" wheels and 126mm rear spacing.

To confirm this, you could put a quick release or other straight small object through the dropouts (as if it were an axle) and measure the distance to the brake pads. A 27" is going to be around 630mm/2 = 315mm in radius to where the tire sits, so the brake pads should be able to extend a little bit closer to the dropouts than this (this is not exactly a way to determine what size wheels the frame was designed for, but just determine that they will work). Depending on exactly when it is from in that era and the quality of the bike, its possible that it would use 700c wheels (which have a very similar 622mm diameter) but very unlikely.

The spacing is the distance inside the dropouts:

from http://farm3.static.flickr.com/2061/1819835696_836e18f8ea_o.jpg

The rear should measure 126mm I would expect, and the front should almost certainly be 100mm (any wheelset that meets the specifications for the rear should also fit the front)


SRAM x5 derailleur fitting So I am a complete novice when it comes to bike maintenance but working on a project mtb, old Saracen rufftrax.

The rear derailleur was knackered so fitting a new SRAM x5, my question is do I need to buy a separate bolt/nut to fit it properly? The derailleur didn’t come with one and the derailleur seems to have too much movement.

The bolt I am on about would be for the hole in the centre of the picture where it attaches to the hanger

I assume you are using the derailleur bolt from the original with the new derailleur. Derailleur bolts are standard M10 x 1.0mm pitch, so that should be fine. The derailleur should rotate around that bolt, as long as it's not loose and does not have any play it's OK.

Without a chain installed the range of rotation will be quite wide, especially if the b-screw is wound out. After installing the chain, just adjust the derailleur properly and you should be OK.

Update:

Make sure the B-screw adjustment washer is in place. If it isn't the derailleur would move laterally on the bushing the bolt goes through.

BTW if you are a novice, there is plenty of bike wrenching instruction on the web. the Park Tool site and YouTube channel is a great resource.


Feasibility of coupling internal hub gear and derailleur Price considerations apart, would it make sense to install together an internal hub gear and a derailleur?

I was thinking of it as a viable way to avoid having the front gears.

Given that most contemporary internal gear hubs are designed to take up the entire width of a normal rear hub (135mm), there isn't space to add a rear derailleur cassette unless you have an abnormally wide rear frame. Perhaps you could try it with a fat tire bike but most regular bikes don't have the hub spacing to do this with regular IGHs.

And would it make sense? Not normally. Most contemporary internal-gear hubs have a wide-enough range (Shimano 7 speed has 245%; Shimano 8 speed has 307%; Rohloff 526%) and enough 'steps' to satisfy most of what you'd want with a derailleur. Bicyclists tend to be conservative and want to reduce the number of moving parts (and thus breakage points) to a minimum: having both IGH and a rear derailleur increases friction and doubles your maintenance and repair profile.

That being said, Brompton 6-speed bikes combine a 3-speed internal gear with a 2-speed rear mini-derailleur. This is in part to make up with the wide spacing of the 3-speed internal-gear hub. It wouldn't have been necessary if you had a 7- or 9-speed Shimano or 14-speed Rohloff, but the Brompton has a very narrow rear frame and only a custom 3-speed IGH fits. The Brompton IGH was initially made by Sturmey-Archer, then they switched to SRAM.

And as @armb has so cogently noted, SRAM does have a "Dual Drive" line that has a three-speed IGH combined with a rear derailleur.  It's unclear if any bike manufacturers in the USA have adopted the DD-3, although @gschenk noted in chat that:

  three speed hubs with seven speed cassettes are/were fairly common here in Germany. It's an old Sachs thing. Advantage: Without a front derailleur a chain guard may be mounted. While it still offers 3x7 gears.
  That dates back at least to the eighties (maybe but seven then). It is rare now, most bikes appear to be seven speed IGH.

Finally, with all that being said, you could use a front derailleur with an IGH rear hub if you wanted extra mountain climbing gearing (there's also front internal-hub cranks). Some people put schlumpf mountain drives on their Bromptons so that they have a 3-speed IGH, a 2-speed rear derailleur, and 2-speed IG front crank.


how can you index a 9 speed 11-46 tooth cassette if the gears arent equally apart I am looking at purchasing a 9 speed 11-46 cassette but on inspection the bigger cogs are not equally apart from the smaller ones.  How would you go on with indexing (I use a thumb shifter 9 speed) if the gaps aren't equal as I'm guessing my shifter pulls and pushes the same amount of cable per click.

EG Cassette Range: 11-13-15-18-21-24-28-32-37-46T these arent equally spaced apart in particular the biggest ring is alot further away from 2nd ring 9 tooth difference than the others that are 2-4 tooth difference.

It sounds like you're talking about the tooth difference, and not the horizontal spacing between cogs.  Most cassettes are "uneven" in this sense.  It does not affect indexed shifting, so long as the derailer can accommodate the max number of links difference and can "reach" as high as the largest cog.


Pinion C1.12 with drop bars? In your opinion, what's the best way to install drop bars on a bike with a Pinion gearbox, in particular the C1.12.

Some of the options I'm aware of:

shifter on bar end
split bars with shifter next to the stem
a stubby accessory mount attached to the fork.
the Cinq Shift:R Road kit, listed on cinq.de for a lovely 700 euro and possibly not even out of the kickstarter phase yet.

The following links are about the Cinq shifter:

https://cinq.de/en/shifting-technology/434/shift-r-road-for-pinion?c=136

https://www.kickstarter.com/projects/1769923126/cinq-shift-r-for-pinion/posts/2625804

https://pinion.eu/en/eurobike-news-2/

Also of great interest is the link below, which lists various ways to install a Rohloff shifter on a drop bar, the Rohloff shifter being not entirely unlike the Pinion shifter. They're not identical, though. Cinq has more finished products for Rohloff and there appear to one or two other manufacturers that produce shifters for Rohloff (but not for Pinion).

Thank you.

Specifically addressing the second of your suggestions

  split bars with shifter next to the stem

This is a bad idea and would strongly recommend against it.

The GMC Denali uses this method in order to fit grip shifters to a dropbar.

The dropbar has been cut through in the middle, allowing the maker to fit the twist or grip shifters.  These will be generally similar in design to your rotary shifter for a flat bar.  The two parts of the bar have been reattached with a two-part clamshell, which holds the bar-halves with set screws.  However, in order to get the thickness in the clamshell, the maker used thinner bars and left a larger hole in the stem.

The beginner rider might not notice the problems.  Once you start putting a bit of power through the bike, you push the bike down with your hands to raise the pedal and eek out some more power.  To have your bars connected to the bike in this manner is not good, and any failure at any speed will have serious consequences.

Somewhat related example of bar-failure. (ok its a pro whose carbon TT bars failed at speed, not because they were cut in half, but its hard to find relevant video)
https://road.cc/content/news/229200-video-pro-rider-takes-nasty-fall-handlebars-are-snapped-clean

Upshot - don't cut your bars.


Why is it not recommend to put V brake levers on cantilever brakes? I understand that V brake levers pull more cable out then cantilever brake levers. However, the argument why one shouldn't put V brake levers on cantilever brakes I often hear and also the only one I found by searching is that by doing that, you will not be able to create enough "power" to brake properly. This doesn't make sense to me, if it is true, can someone try to explain why it is true? The thing that does make sense to me is that by having that setup you will not be able to use the brake "half-way", that is, either it will be far from rim, or when you pull the lever slightly it will already be "very tight" to the rim braking "100%".

It's the old lever law: You can either increase force or movement distance at the expense of the other; the product force times distance remains the same.

The V-brake levers pull more cable, so they pull it with less force. If you pull cantilever brakes with a V-brake lever, that force reduction means that you get much less braking power when you put the same force into your grip.

Whether that's a problem depends entirely on you. I have strong hands, and I use good brake pads, so I can easily apply too much force on my V-brake levers, and consequently wouldn't hesitate to use it on a cantilever brake. If you have weaker hands, and/or worse pads, you may not be able to comfortably get enough braking power out of a V-brake-lever-actuated cantilever brake.


Fundamental principles of tire friction for off-road biking This is a two-part question.

I've been watching various videos and getting various advice about mountain bike cornering. My impression is that all of the advice cannot be true, because the advice, taken together, seems self-contradictory. Also, some logic out there seems rather disconnected from the physics.

A few years ago, I read this book on race car driving: "Going Faster! Mastering the Art of Race Driving". It is the best physics-based explanation of car handling I've seen. Based on the laws of physics, each tire has a maximum amount of traction for a given amount of downward force per tire. I want to point out two things that result from this:

If you need more traction, you can: (a) get stickier tires, (b) increase contact patch, (c) increase downward force (i.e. the 'normal' vector, perpendicular to the surface).
For a given amount of friction, it may be used for some combination of acceleration (forward), braking (backward), or cornering (sideways). By combination, I mean the sum of the force vectors. So, the more friction you use in acceleration or braking, the less you have available for cornering.

Unless I hear a better explanation, I think the above explanation above serves as a useful fundamental grounding of tire traction, whether it be on-road or off-road.

Question, part 1: Is my summary of the physics detailed enough to be useful without overlooking any key aspects? Are there problems in borrowing the logic of automotive tire grip and applying it to mountain biking?

Here is one way to apply this knowledge. As an example, I heard something like this from a video about mountain bike handling (sorry, I lost the link):

  "pedaling out of a corner gives more traction at the rear wheel" (paraphrased)

This seems bogus to me. If you pedal, you are asking the rear tire to use grip for acceleration, meaning less is available for cornering. Question, part 2: Is my logic correct?

So let me get this straight before it becomes a mess:

  ..increased downward force from pedalling..

When you pedal the downward force is not increased - you are not getting any heavier. You can only increase the downward force on a rear wheel by shifting your body back - this will decrease the downward force on front wheel though, which is good for steering actually. Controlling your body position is easier and more precise when not pedalling.

Cars actually act differently while cornering than bikes - bikes lean into the corner. But for the tires and traction that part is the same and you are right.

Maximum cornering angle is proportional to the coefficient of friction of the tires to the gravel/road/whatever (this is only affected by the tire tread and tire compound). The faster you want to go in corner the more you need to lean-in with you center of gravity. So if you manage to throw your body off seat closer to the ground the tires won't have to lean that much - see the picture - giving you a better cornering grip.

So the correct way is: Pedal before the corner to get your speed, then off the seat and control the centre of gravity for maximum cornering grip (you are not able to pedal now), keep weight on both wheels equally for steering, focus on hitting the corner apex (this is actually the most important part), then pedal again off the corner.

With bikes and cornering also the width of the rim plays a role. If running lower pressure to get more grip (bigger contact surface for the treads to bite into ground) with narrower rims you can get a tire blowout (when tubeless) or lose balance as the tire sidewalls have less support. Wider rims provide better support for cornering (but wider are also heavier giving less acceleration).

TL:DR: your logic is correct, tire tread veeery important, pedaling is BS, use your body weight to your advantage, lower pressure, wider rims.


Any advice for wobbly/slightly bent bicycle rims on older bicycle? I have an older RWC Female bicycle that I bought second hand a year ago and it has now in the past weeks began to feel extremely wobbly and shaky when I am riding it. It feels as if both the front and back wheels are wobbly.
I continued to ride the bicycle having a plan to take the bike into the shop to get looked at and hopefully fixed. Before I was able to do that my back tire blew out and is now completely flat.
I took the bike to the shop today and the mechanics there stated that the front rim (and maybe the back rim) is bent from bike stands etc. The ISO size of the RIM is 37-590, and the mechanic after looking at the wheel stated that this rim size is old and therefore will be very difficult to source and that they do not stock this type of wheel size.
Could you suggest if the wobbling of the wheels is due to the rim being bent (I can't see the bend with my eye as I am no expert) and whether the rim is able to be fixed with tools or if a whole new rim is required to fix the bicycle?
We are in Europe so if you know any suppliers of these size wheels that would be great too.
Thank you!

ISO 590 is indeed an older wheel rim size, also known as '650A' in the French system of wheel sizes (See this page for more details). I did some quick internet searching and found that 590 rims are available in the US at least. If you need new wheels you can have them built up, possibly using the existing hubs.
If you want to check yourself if the rims are out of true (or how bad they are) that's easy. Hold the bike off the ground, spin a wheel, watch the rim where it passes a brake pad. If the rim appears to move side to side or up and down as it passes the pad more than a few millimetres the rim is out of true.
Depending on how bad the apparent movement is the spokes may simply be adjusted, or you may need to have the wheel re-built with new spokes, or you may need new rims. What you  should do is look for a local bike repair shop that offers wheel rebuilding and have them evaluate the wheels and make a recommendation.
An additional complication is that your hub bearings may be worn out or badly adjusted. Hold the bike off the ground, grab a wheel by the rim and try to push it side to side. If you can feel the wheel moving more than just a tiny bit there is an issue with the bearings (I suspect this is contributing to the 'wobbly' feel of the bike. With old wheels there is a significant chance the bearing surfaces inside the rims are worn out which will mean you need new hubs. Chances are your bike need hubs for an obsolete rear triangle and fork width, but these are available if not common. Again, have a bike repair shop evaluate the hubs to see if they can be re-used.
Depending on what you determine about the state of the wheels you'll have to make some decisions about how much money you want to spend on new ones.


Should I be able to peel off a glued tire patch? One of the things that I've noticed with the low-cost tube patch kit that I bought is that I'm able to catch an edge of the glued patch with my knife or fingernail and peel the patch off the tube like a bandaid.  While handy for repatching, it doesn't give me a whole lot of confidence in this kit.

Shouldn't a glued patch be essentially so welded to the inner-tube that it's unable to come off through any normal means?

** This is a cheap kit with glued patches (ie, separate glue and patch, not a "glueless" patch)

No, you shouldn't be able to peel a patch off, regardless of if its a glued or glueless patch.

Confirming that this is a wet-glue patch that has failed to stick?  Possible causes for failure of a patched tube

You didn't clean the tube properly
you didn't buff the tube properly
There is a ridge in the tube which is in the way, has left a tunnel of weakness under the patch
its a latex tube not a butyl rubber tube
The patch was cheap and/or nasty, or possibly old, or damaged by heat/sunlight.
The rubber cement was cheap (watered down or just not very good)
The cement was really just a glue (cheap again)
The cement was old, more-so if it had been sitting around open for a while since your previous puncture fix.
You didn't wait long enough for the cement to dry - 10 minutes is my normal wait time.
You didn't spread the cement out far enough on the tube.   It should make a wet area bigger than the patch.
You stuck the patch on upside-down, so the wrong side was out
When unpeeling the patch backing you touched the surface, and left finger oil or other contaminants enough to interfere with bonding
You didn't press the patch on firmly to the tube.  I use a tool as pictured below, but a round coin works well too.  You have to roll it over the whole patch, back and forth over and along the edges
Did you inflate the tube outside the tyre?  Without restraint, the tube will stretch, which causes extra strain on the cement.

These aren't likely to be the cause of the patch peeling off

You missed the hole completely, or far enough so that it was to the edge of the patch
The hole is too big to be patched.  Cuts over 5 mm generally mean a new tube, and holes more than 2 mm in diameter tend to not patch so good.

EDIT: Other points I missed
 * patching in the rain or dampness - water/cold stops the cement from curing as quickly, and being wet makes you hurry.

Personally I'm not very good at punctures, I have a success rate of 2/3 repaired okay if I start patching a tube.

In a pinch, I've successfully cut a round piece of spare innertube, buffed and glued its innerside, waited 10 minutes and slapped it on the buffed and glued inner tube.    It worked perfectly and is still on the bike today.

I know yours isn't a glueless patch, but for completeness:

By comparison, glueless patches are really glorified stickers.  They don't bond to the rubber of the tube as well as one with vulcanising fluid/cement.  But they're also a lot quicker to buff, slap on and ride more.  Their maximum pressure seems to be lower too, so bad for roadies on 100psi, workable for MTB on 30psi.


Running multiple dynamo lights on a single dynohub I have a Shutter Precision PD8 hub, and a B&M headlight. I happen to have a spare B&M headlight of a different model in my parts bin. I'm thinking about putting the second light on just to have extra light, and potentially to aim it lower so I can see close-up better. Can I just patch the second light in? And if I do, should I put it electrically parallel or series? And will it be any brighter at all, or will each light just be proportionally dimmer?

Most bike dynamos produce roughly constant current, so if you ride fast enough, doubling the resistance by wiring two lights in series gives 12v, neatly split between the lights. The classic setup in old days was two lights in series and switch to short circuit one when riding slowly, so that the other would get the full voltage.
Some new LED lights designed for dynamo can take advantage of this feature even with single light, so it would make sense to not add any current limiting to new models. The only way to know if it works for any specific model is to try.


Can I add gears on a bmx? Just asking if it is possible.
My friend added gears, but won't it damage the look or my cycle?

It is possible. There are a lot of 20in wheel bikes with gears. There are some problems, though:

The frame might need to be opened so that the larger hub can be inserted;
There are no derailer hanger in bmx frames, so you'll have to use an adaptor, or a simpler derailer model which is mounted together with the axle;
The derailer itself is closer to the ground compared to 26in wheel bikes, but this might not be important, since many folding bikes are that way.

The least of your problems would be "looks"...

OR...

You can throw some more dollars and install an INTERNALLY GEARED HUB, which not just wouldn't break the clean looks, but would actually benefit from the horizontal dropouts found in BMX frames. But those are usually quite expensive.


Why would semi-solid fork make whizzing sound? Alert the semi-solid fork is probably not the right terminology, it shows that I don't know 100% whether the work has some sort of inner suspension.

My bike is almost this one but I feel there is some sort of inner suspension thing because there is a rubber or it is just decorative and I just imagine it is suspension due to tires. There is a small rubber cork to the fork so I think it is to oil the suspension. I looked inside the rubber thing and there is suspension looking metallic thing. Notice the small rubber cork for the oil, I have never put anything there.

I haven't yet dissasembled the bike and no specific specs because I bought it as 10k-driven used bike. So no precise diagnosis yet.

Description of the sound

The front makes a lot of whiizing sound. When I drive with weight on the front, the sound disappears. When I slow down even a little (i.e. the force is less on the front due to de-accelerating), the sound emerges again. Because of this observation, I thought that the fork is not rigid-fork but with small suspension. What would you suggest to do with the fork? I will disassembly it and apply some sort of special lubrication (it may be just that lubrication is eroded) or will I do something else?

From looking at the picture, you do have a front suspension, of a type you would usually see on "hybrid"/"comfort" bikes, with a very small amount of travel. I can't think of any way that a problem inside that suspension component could cause a whizzing noise, though.

I think it's more likely the wheel rubbing against something, such as a fender, brake pad, etc.  If the wheel is off true (not straight) or not seated properly on the fork, it could be slightly rubbing against something but get better with some weight on it.

What's on the front of the bike that gets anywhere near the wheel? Front brakes? Fenders? A basket or rack? Lights? Disk brakes like shown on that bike?

Here's some things I'd try:

Does it make the noise with no weight on it?  Can you hold up the front of the bike and listen? Figuring out exactly where the noise is coming from would be very helpful.
If you hold the handlebars or fork steady and try to move the wheel sideways, is there any play (does it wiggle or is it solid)? The wheel should spin freely
Look at one of the brake pads (or something else that's close to the wheel) and spin it; can you see the wheel move side to side as it spins?
Wiggle the spokes. Do they all feel the same, or do some feel looser than others?
If there's anything optional, like fenders and you still haven't found the source of the noise, try removing those and see if the noise goes away.


Why aren't sealed hub bearings common place? Loose hub bearings may be cheaper to mass produce, but why wouldn't sealed hub bearings be one of the first upgrades to a bike?  It seems that most of us choose loose bearings.  I'm thinking of putting in a set of sealed bearings front and back and be done with it.

Cone, ball and cup aka traditional wheel bearings are the simplest and cheapest expression of wheel bearings. Simple to manufacture, easy to maintain and repair with the simplest tools and a handful of standard parts that have been around for more than a century in the remotest locations. And the wheel will even turn after emergency repair when, say, one bearing ball is missing, while a toast sealed bearing means a break-down.
Sealed bearings require high precision manufacturing, logistics & stock-keeping, special tools and trained mechanics.


New front derailleur I need to replace the front derailleur on my friends bike, this one is old and rusted, its a shimano FD M191. I've read a bit about what I need to know before I buy a new one but I just wanted to be sure before I make the plunge. Please excuse my newbiness...

The current one has a down pulling cable fix and serves 3 cogs, from what I gather these are the only factors that I have to ensure my new derailleur caters for. Is this correct? Can anyone recommend me something sub $30 that would work, and is there anything else I need to consider?

Thanks.

There are several criteria when selecting a front derailleur. Top, bottom and now side cable pull. Some Shimano models are both top and bottom compatible. The mount type, seat post clamp mount (correct diameter or have an adapter), bottom bracket mount or direct mount. The derailleur must be compatible with your crankset size. This is usually specified by a maximum number of teeth. It must also match the number of ring gears on the crank (double or triple). It must also match the chain 8,9,10 etc, speed. There is some overlap on 7 and 8 speeds that will work with both.


What causes a slight rhythmic knock in the pedal? My left pedal is sending a slight knock to the sole of my foot at every turn, at the 1 o'clock position. What could cause this? It happens on all chainring-sprocket combinations though not with the same intensity.
Edit: this is a flat pedal, JIS square taper bottom bracket.
Edit: By "1 o'clock" I mean there's a click in the left pedal when the right pedal is exiting its power sector/downward push, and the left pedal is about to come "over the top" ready for its own power stroke.
Edit 2: Solved! This is a brand new crank set that I installed onto a year-old bottom bracket. I must have installed the left arm wrong. I took it off, cleaned and re-greased the crank bolt tread and the faces of the square tapered spindle, put everything back together, tightened with care, and the knock is now gone.

It can be many kinds of stuff. The obvious to look for are the pedal bearings, the bottom bracket bearings or the interface between the crankarms and the bottom bracket (for 3-piece cranks) or the interface between the crank spindle and the left crank (2-piece crank), but many other things could do it.
It is useful to test the pieces in isolation. Disconnect the chain and try to turn the crank. Try to turn the pedal on the pedal spindle. Do you feel any grinding or clicking? That would point to the right spot. Try to tighten the cranks to the required torque (depends on the exact type, 2-piece vs. 3-piece, the brand...).


Can a 10-speed chain be used with a 9-speed cassette? I have an extra 10-speed chain I would like to use with a 9-speed cassette on my mountain bike. Will this combination work ok?

The 10 speed chain is narrower and will work. Not ideal and the shifting might not be as crisp.

Since you have an extra chain you can use it, but if purchasing new I would get a 9 speed chain.


Any experience about radially-laced hub flanges actually breaking? Most hub manufacturers forbid lacing spokes radially, mostly because there is less material in the radial direction away from a flange hole than in the standard 3-cross, tangential lacing.

(UPDATE: as it appears, the actual breaking point is the material betwen consecutive spoke holes in the flange, the spoke holes acting like a perforated-toilet-paper effect...)

I have previously laced a Shimano front hub radially and rode it a lot, and nothing happened. Some friends of mine have done the same in the past (allways front wheel, always XC mountainbike), and nothing happened either. Currently, I have just laced another hub radially, and I am pretty sure nothing evil will happen, but still there is some discomfort for doing a theoretically Wrong Thing.

So, I want to ask you about FACTS (disregarding what manufacturers say): is there any WITNESSED (by yourselves, not internet stories) evidence that radially spoked FRONT hub flanges have ACTUALLY BREAKED? Any photos, stories, or preferrably shop experience?

(ANOTHER UPDATE: as already mentioned, there are a lot of photos and stories about hub flanges broken with radially laced spokes. But, as it turns out, if the search terms contain only "broken hub flange", and not "radial", there are also a lot of photos and stories of broken flanges with standard cross-laced spokes. This makes me think of flanges braeaking for a lot of possible causes, but when this happens with radial spokes, it draws more attention and provokes some confusion bias about causality, relating the failure to the spoke pattern instead of other form of abuse or material wearing.)

Thanks very much!

While it is possible for a hub flange to fail due to radial lacing, if the wheel is built properly, to proper tension, it doesn't happen, generally.

The reason it happens is because the amount of material between the spoke head and the edge of the flange is least when the spoke is pulling directly to the edge.  Under normal usage, the flange has more than enough strength, even when laced radially.

However, if the wheel is laced with too much tension, or if the wheel is placed under abnormal stress, like when used for braking on a fixed gear, then the hub flange is more likely to fail when radially laced, than when laced with a proper crossing pattern.

It can still fail, even when crossed, but it is far more likely when laced radially, due to the smaller amount of material, and more direct tension on the flange.

I have used radially laced wheels, mainly for BMX racing as a kid,  I have had only one failure of a hub flange, though, and that was on a Bontrager Race XXX Lite rear wheel in 2003. That wheel uses a radially laced, paired spoke pattern, which I do believe contributed to the failure.  They are also excessively high tension wheels, due to the low spoke count, and I think it took both the radial pattern, and the excessively high tension to cause the flange to break.

I hope that helps.


What are these two "clips" on the bolts holding by rear disc brake bracket to the frame? My rear disc brake is attached to a bracket, which is attached to the frame.
This bracket is held by two bolts that each have a clip on them:

The clips are clamped around the bolts, and can easily be twisted around the bolt (without the bolt moving).

What are they for?

From https://www.jensonusa.com/Shimano-XT-BR-M775-Caliper-Fixing-Bolt:

  Keeps the bolt from backing out. Torq the bolt then slip the lock over the bolt head and rotate in the direction the bolt would unscrew unntil the tabs hit something. This will stop the bolt from turning if it loosens.

Also: https://bicycles.stackexchange.com/a/29154/908


Are brake lever reach limit screws necessary for any reason? I have some generic cantilever brake levers on my MTB.  The brake reach adjustment screws are normally fully wound out, so are not limiting the brake's reach at all.

Can I remove them permanently ?   I can't see any downside?

Generic image showing Reach Adjustment Screw

Their purpose differs between hydraulic and mechanical brakes.

On these cantilever brakes, the purpose is simply to adjust the rest position of the brake. If you have the screw fully wound out, you should not feel any difference if you remove them.

BUT there is be a real difference in properly bled hydraulic disc brakes:
Here, it is used is to adjust the point at which the brake actually starts to grip to adapt the brake to your hand size. On hydraulic brakes, this is the only way to do that (in contrast, you can e.g. adjust the cable length on cantilever brakes). If an adjustment screws exists, it is most often an integral part of the lever that pushes on the cylinder and cannot be removed. (Especially lower-end brakes do not necessarily have them.)

Depending on your hand size, it can be really uncomfortable if they grip too early. For example, I rode some trails with the brake (BR-M486) gripping too early. To keep my fingers on the brake meant a hand position that got really tiring after some bumpy sections. Then I adjusted the screw so that I could keep the lever close to the handlebar in a rest position and my hands never got tired from that again. (Of course, a similar thing probably goes for the brake point being too close to the handlebar.)


Is it a good idea to buy second hand bike model that has been discontinued? I am a new rider looking for a road bike.  I found a deal to buy second hand 2017 Orbea Avant M40 size 51 for $800.  I see that this model is discontinued by Orbea. Will it be a problem to find parts should I need some repairs done in near future?

My last bike was Diamondback Calico - Aluminum frame. I had problem going up on steep hills. At max I have rode a bike for 20 miles in one ride, and my average in the summer would be anywhere from 10 to 25 miles.  This year planning to ride for a 40 miles ride.

Generally it's absolutely fine to buy a relatively new bike, and not worry about component availability.

Bicycles are not like cars that have specific components for each model, or at best some component sharing across a manufacturers models. In general, practically all bicycle components are standardized so that bicycles can be built up (or modified) with components from many manufacturers.

There is an increasing trend for some manufacturers to integrate the seatpost, stem and sometimes handlebars of some models into the frame design for aerodynamics or to facilitate internal cable routing, but the Orbea model you mentioned does not have this.


How to center Gates belt drive? The Gates belt is running slightly off-center on the rear sprocket. Does anybody know how to adjust the rear sprocket/wheel such that the belt runs centered?

Thanks

The short answer is that they had a bunch of problems with this on the center track-less version(s), and added the center track to finally solve it.

For the belt to not get off-center, the gears need to be in exactly the same plane.

Rear triangle alignment, dropout alignment, and BB shell alignment are all potential factors. The former two are things you could do something about on a steel frame, but the last isn't. (Shell alignment is also not a common issue, just a possible one.)

Imperfect chainline (or whatever you want to call it when it's a belt, not a chain) also causes it. If possible I recommend you get the frame aligned before even starting in with addressing chainline in this case. The reason is that rear triangle and to a lesser extent dropout misalignment affects your chainline measurements, but chainline can't really be used to compensate for alignment problems here.

The belt also needs to be properly tensioned. But if there are problems with alignment and chainline, tension won't solve them.


Back wheel jumping out of rear dropout with child transporter Some days ago, I was riding my bike towing a child transporter. I was going steep uphill and put quite some force on the pedal. Suddenly, I heard a loud snapping sound and the back wheel was blocked. After dismounting the bike, I found that the back wheel actually had jumped out of the rear dropout. I have a Shimano Alfine with a solid axle and had no tools with me to tighten the axle nuts.

Luckily, nothing worse has happened than that I was standing in the middle of a forest below 0 °C with my two year old daughter in the child transporter and a bike with a loose back wheel. The way back to civilization was not too far, so we managed all right, but I would like to prevent this from happening again.

I have been using the child transporter on a regular basis for a year now, and nothing similar happened before. I recently (two weeks ago) switched to the Alfine hub from a derailleur setup which had a quick release (might be relevant for this case). I am very sure that I had tightened the axle nuts enough when mounting the back wheel.

What I suspect is that the force exerted by the child transporter in this steep uphill passage was big enough to rotate the bracket holding the shaft of the child transporter counterclockwise, thus partly loosening the axle nut and releasing the back wheel.

Now my questions are: Do you think that this explanation is correct? Have you made a similar experience? And most importantly: What can I do that this will not happen again? Thank you for your help.

Update after comments and Chris H´s answer below:
I had a closer look at the bracket as well as the green washer on the left side, see photos below. The bracket has some grooves on the inside which are probably meant to increase friction when mounted directly on the dropout without washer, like when using a quick release. The green color from the washer is rubbed off where it was in contact with the bracket. So there is evidence that there was some movement going on and that this is probably the critical spot.

Update after doing some further research: The way I mounted the bracket on the axle of the back wheel together with an internally geared hub is not how it is recommended by the child transporter manufacturer and should not be reproduced by anybody. Instead, they have an adapter which replaces the axle nut on the left side for this purpose (https://www.thule.com/en-gb/accessories/thule-internal-hub-hitch-adapter-shimano-_-20100797). This is the way I will go, and this should be considered when changing from a derailleur setup where there are no washers to an internally geared hub which needs the non-turn washers.

Now some photos in order to support the descriptions above:
To give a detailed impression of how the child transporter is attached to the bike, here are some photos. First an overview of the situation:

Close-up of the bracket holding the shaft of the child transporter:

How the bracket is mounted on the left side:

How the back wheel is fixed on the right side:

Inside of the bracket holding the child transporter shaft:

Green washer after having been used in contact with the bracket:

The green anti-rotation washer is at least part of the problem. Its purpose is to prevent the nut rotating easily , but with the bracket in between, it can't, and any torque on the bracket is transferred to the nut.

I expect you'll have better results if you put the washer outside the bracket; this works on mine with QR skewers. Even omitting the washer might be better than what you've got now. With an extra part in there you may need to do things up a little tighter than normal in addition.


Can you use SRAM 11-spd trigger shifters such as NX and GX with Shimano 11-spd derailleurs such as SLX and XT? I have read some threads that say these work well together and solve the hard shifting issue with the Shimano shifters.

SRAM and Shimano use different cable pulls and derailleur actuation ratios, so their shifters and derailleurs are nominally incompatible with each other.

This Art's Cyclery blog page documents derailleur pull ratios, sprocket spacing and cable pull for a variety of derailleurs.

SRAM and Shimano 11 speed mountain use the same sprocket spacing - 3.9mm, so for shifters and derailleurs to be compatible they would have to designed for the same actuation ratio.

Shimano 11 speed mountain derailleurs have an actuation ratio of 1.1. SRAM has two 11 speed mountain uses two actuation ratios: 'Exact Actuation' is 1.3, 'X-Actuation' is 1.12.

NX and GX use the X-Actuation ratio, so maybe the ratios are close enough with Shimano 11 speed mountain that they are compatible. The difference between 1.1 and 1.12 is about 2%, so if you indexed the middle sprocket correctly the high and low sprockets would be out by 3.9mm x 0.02 x 5 =~ 0.4mm.


Is my brake line bad? I recently purchased an old bike and got the brakes replaced. My front brakes are working as expected and my rear brakes are not. I am squeezing my brake lever which has a lot of resistance, but isn't really tightening my brakes. My brakes are moving a little bit but the line flexes a lot.

My brakes are properly installed and the line on that end is attached properly. Any ideas what the issue could be?

From your description the brake cable (or the rear caliper) may be rusted up.  (Although, if you "got the brakes replaced" whoever did that should have checked brake operation and lubed the cable and caliper if necessary.)

Observe the rear caliper as you squeeze the handle -- gentle motion on the handle should result in smooth closing of the caliper, and you shouldn't feel any significant resistance in the brake lever until the caliper is closed against the rim.

Do note that there's a lot of stretch in the rear brake cable (because it's so much longer than the front), so once the caliper is closed against the rim the cable will continue to stretch as you squeeze.


Transfer components from a Scott Spark 20 to a Orange Alpine 160 My beloved Scott Spark 20 with an all carbon frame bit the dust after many years. I would like a new bike to rise out of the ashes of the spark and have seen a 2nd had Alpine 160 frame I fancy. Is this a good match though, the Spark has 120mm travel forks and I guess the Alpine has 160mm rear travel, would that make for a badly handling bike?

They are not even vaguely comparable.

The Scott Spark is a short travel XC bike, and the Orange Alpine is a big burly enduro bike.

An enduro bike will need a longer fork as a bare minimum, but even if you move over the rest of your components, will not behave anything like an XC bike in terms of pedalling or handling.