How to carry a trumpet for long trips I'm a trumpet playet and I would like to carry my instrument with me on long trips. I have a quite light bag for my trumpet which can be carried as a backpack, but this might be troublesome for long trips. I would like to somehow attach my trumpet (probably inside of a case) directly to the bike. Currently my bike is equipped with a luggage rack at the bag to which saddlebags are attached.
Any idea is welcomed !

I'd suggest a top-of-rack bag for your instrument, because its more aero when the load is in-line with the rider.  If there's no bag big enough, use a series of bungee cords to securely strap the case to the top of the rack, lengthwise.  Feed a cord under the case's handle too.   If this becomes a regular thing, you can even make a "tray" permanently secured to the top of the rack, exactly the right size for your case, with lips/sides to stop it sliding out.
You could use panniers / saddle bag on the side of your rack, but that tends to stick out into the wind a big more.  There's also the increased risk of damage being stuck out.  But a pair of panniers lets you carry other stuff on the other side, and still use a top rack bag/tray.
Carrying the trumpet on your back is a workable solution too, but it increases the sweatiness of your back, and can exacerbate damage and injury in the event of an accident so its not ideal.
Carrying it inside the frame triangle, or above the top tube is probably not going to fit, and will interfere with your legs while pedalling.
A front rack might be a good idea too - you can see it while riding.
A trumpet is not really large enough to need a trailer, so that can wait until you upsize :-)

Whatever you choose, also consider waterproofness.  Most instrument cases have a velvet / velveteen liner fabric which doesn't like getting wet.  If you have to ride in the rain, consider a "dry sack" large enough to hold the whole case and seal up.   Good for a towel and dry clothes too.  This would also help prevent marking of your case by vibrations against the rack.


Which way does the seat clamp go on the post? I have one of the older style seat clamps, the one with the bolt all the way through it with two male ends that tighten on either side. I'm not sure if the bolt side goes to the front of the post or the back of the post, or if it makes a difference. I have it to the front right now because it makes the seat closer to the bars and shortens the cockpit nicely, but looking at my friends bike, it seems like it may go the other way, and I don't want to bend or break anything.

Which way is the seat clamp supposed to go, to the front or the back? Does it make a difference?

Here is a picture of the clamp:

If you align the gap of the clamp to sit over the gap of the seat post, you'll need much less clamping force to keep the seat from sliding down into the seat tube. There are likely some riders who place the clamp in a position they like strictly for the aesthetics, while others go for functionality. From what I remember, the position is determined by how much force you intend to apply to keep the seat from moving left, right, or down.


How to avoid turning the spokes while tuning the wheel When I tried to practice tuning my wheels, I found my spokes turn with the nipples. I tried to drop some lubricant on on the nipples, but I had the bike for two years now and there are a lot of dust clog in it. So the lubricant doesn't help too much. What can I do in this situation?

When I build/maintain wheels, I specifically make an extra quarter-turn to the nipple and then quarter-turn backward to release the rotational tension. This was recommended by Sheldon Brown

Lubing the spoke can help, but if your spokes are rusted, you might as well replace them with the new ones.


Is it ok for the trunk bike rack to rest against the glass of a hatchback? I feel like this is one of those obvious questions, but I have been unsuccessful at finding an answer (even in the manual for the rack!).

I just purchased a bike rack (only holds 2 bikes) for my Subaru hatchback. I have found that I can mount the rack such that it doesn't press against the glass of the back windshield, but mounting it so low requires that I remove the front wheel of my bike (at least to make me comfortable, it probably would be fine).

Can I instead mount it so that the rack presses against the back windshield?  Is this likely or possible to break the back windshield?

Note that my back windshield is not cracked, though the car is 10+ years old.

EDIT: The bike rack, which is a Thule Thruway Pro 2, uses two foam-padded bars as the main contact points between the rack and the car.  I figure that this question is probably valid for any bike rack with padded bars as the contact points, not just Thule bike racks.

Being both a hatchback owner and a trunk rack owner, I can tell you yes...and no.

I've got a Saris Bones 3 rack and the feet have etched the window slightly. While the feet are of a more rubbery plastic, I think it's when there's dirt and grit underneath and moves (even unnoticeable movement) it grinds at the window. It usually cleans up pretty well, but I can tell where the feet marks are.

I would recommend putting a sock or other cloth over the feet (the body ones wouldn't hurt either). Also, make sure the contact point is clean, which means lossening or removing the rack to clean behind it.

Lastly, I've never had an issue with the rack slipping or moving, but most of the weight (even on your type of rack) will be going to the lower feet or bars.


Attaching LED strips to bike I'm interested in attaching LED strip(s) onto the frame of my bike. Are there features of LED strips that I should be looking for when making my decision of which one to get? What's the best way to attach them?

I plan to use the lights only from time to time, and would not mind having them battery powered (I would use rechargeable batteries anyways). In terms of colors, I would love to have the strip able to oscillate in patterns (most do in any case), though this is not necessary.

Sense this topic has re-opened i will submit an answer.

For custom frame lighting i believe it would be easiest to adapt a product that is already intended for use on bicycle frames or wheels such as what it seen below. It is a weather proof battery box wired to a silicone tube filled with chip LEDs, basically a rope light, the idea is the battery box attached to the hub, and the rope portion is woven through the spoke and centrifugal force with a little help from zip ties keeps it in place.

They come in a variety of colors from a variety of manufacturers. Thus is why i think this would be the most simple and cost effective form to adapt. You could simple attach the battery box beneath the stem or any area out of the way and zip tie the rope where ever you want it on the frame. you could combine colors and get creative with it quite easily.

I know that the US distributor J&B sells them so most bike shops in the US should be able to get them, and ive seen them other places on the net as well. Their rather popular for customizing cruisers.

Heres a couple images of them installed:


Friction shifter for Rohloff speedhub? This is might be trivial for someone who actually have a one, but after countless hours reading and watching about the Rohloff speedhub I can't answer this question myself.

AFAIK the OEM grip shifter is not the most loved feature of the system. It can't be used with drop handlebars, - as all other grip shifters - it is slippery when wet, and it is not a trigger shifter. So far I have found 23 quirky ways to overcome the handlebar issue, and one trigger shifter review.

My first idea would be just to use a one-cable (maybe indexed) friction shifter, and some counter pull mechanism on the other end of the cable to replace the second cable. Seeing the how much effort has gone into mounting or replacing the original shifter, there should be something why this won't work.

So why? Why there is no friction shifter available for this hub?

The Rohloff shifting mechanism is designed specifically not to include a spring or other mechanism to move one of the directions. Since it pulls so much cable, it would indeed be difficult to do a single friction shifter. The 2-cable system is feature, not a bug, since Rohloff believes the 2-cable system to be more reliable than one cable + spring.

They discuss spring mechanisms as prone to failure. I've had a high-end SRAM x.0 derailleur main spring break on me in the middle of a commute (fixed it with a zip tie in the middle of the cassette so I could at least get home with the 3 rings in front as my gears), so I've seen them go myself. The 2-cable system also makes it pretty simple to keep the bike going should one cable fail, since you can shift the bike with a wrench, something that wouldn't be possible if there were a spring trying to return the hub one direction or another (unless that were accounted for in some design).

That said, there is a trigger shifting option (ed. by cinq5) which is using 2 triggers. It's described in a blog post by Cycle Monkey.

  I love my Rohloff but I'm no fan of the grip shifter, only because it
  slips in my greasy hands. If it just had a different texture, I'd be happier.

Best solution I've seen was to save a few of those giant rubber bands, that are used to tie broccoli in stores, and apply them to the shifter with a cross pattern for an easy friction increase. I need to go visit the produce section myself.


What should I expect from a bicycle service? I'm thinking about getting my bicycle serviced for the first time to make sure it's entirely roadworthy.

My question is what should I expect from a bike service from a professional?

i.e. what checks are carried out, what maintenance is done, to what price level will parts be replaced within the service price?

And finally what price should I be paying for a service? (London UK)

EDIT: I'll further add there might be a minor problem with my back dérailleur, no parts needed to fix, just the know how...

These services vary wildly from shop to shop.

My local shop will look at any bike and tell the owner if it's safe to ride. And of course, they'll tell the owner how much it would cost to make it safe if it's not already. They're pretty honest about it, but of course I can't guarantee that other places are.

Most shops offer a free "tune-up" with the purchase of a new bike. This usually includes minor maintenance and inspections such as tightening bolts, airing up tires, adjusting brake and derailleur cable tightness, checking that the wheels are true, etc., but no parts replacement. If the bike was not purchased from the shop in question, they will usually offer the same tune-up service for a relatively low fee, $25 (~£16) US where I live.

Many shops offer additional service levels beyond this. They may include replacing cables and/or cable housing, bar tape, brake pads, actually truing the wheels (this can be a more time consuming job and may not be included in a basic tune-up), and perhaps even a bike wash. These tune-ups can get fairly expensive, $100-$150 (£67-£100) US.

Exactly how much you pay for any tune-up will depend on exactly what combination of services a shop offers and the amount of local competition, so you should really shop around.


Why should one clean a chain? I do understand that this may sound like a troll question but please bear with me.

I've always been a maniac about drive train cleanliness until I got a 11 speed bike and realized I didn't want to spend the ca$$$h on the only reusable 11 speed chain link. Cleaning with the chain on the bike is too messy for my taste. Therefore I rode ~2k miles (new bike) with only periodic lubrication (using a good lubricant). Result? Nothing obviusly bad happened. Drive train is unsightly but quiet. Shifting is impeccable. Which made me wonder why should one clean a drive train at all: the process is cumbersome and a shiny drivetrain gets messy in no time with road only use under dry conditions. So why bother at all? Is there any objective study on the effectiveness of drivetrain cleaning?

A lot of people are now out of the habit of doing chain cleaning beyond wipe down level.

The reason to clean thoroughly is a marginal improvement in wear life and performance. But the key word is marginal. What you get for the effort is below the threshold of what many would consider worthwhile, especially riding recreationally.

Note that the expense level of your chain is a major factor here. It takes the same amount of time to clean a $13 basic 8-speed chain as it does an $60 Campy Record 11 chain, so clearly there's more economy in maximizing the service life of the latter.


Alternative uses for RockShox fork oil I currently have a small bottle of red RockShox 15wt fork oil left over. As I no longer own a RockShox fork, this oil seems pretty useless to me. (Fox specifies different oil weights, and I can't figure out whether the oil would be ok to service my new 34 Rhythm fork. Preliminary research ranges from "usable in the lower legs" to "better safe than sorry, so use only Fox oil".)

Suppose I can't use the oil for the lower leg service of my Fox fork - are there any reasonable bike-related use cases for the oil? Probably the oil is too thin as a chain lubricant, right? Or should I rather try to find someone who actually needs it for his/her fork?

As an aside: There are loads of questions on the internet about the reverse case: "What oil can I use instead of the manufacturer-recommended oil?" But I can't seem to find an answer to my question.

Offering your remaining oil on a local marketplace might be a good idea. While servicing an older RockShox suspension fork, I spilled out the original oil and needed to replace it. Costs were greater than $10 for sourcing this. My LBS offered me a slightly different weight from their old stock, so I got lucky. During the search I would have appreciated picking up a slight amount of shock designated oil / lubricant locally.


Why are aero bars usually disallowed in gran fondos? Why are aero bars usually disallowed in Gran Fondos (cyclosportive events)?

I'm just curious.  I would think it would be a useful piece of equipment when riding 100 miles.

I now realise "gran fondo" is American terminology for "cyclosportive". That sort of event falls loosely between audax and racing. The randonneuring community prize responsible riding, and tend to frown upon behaviour or equipment that could be deemed "antisocial". For example, most audax events require riders to fit mudguards, for the benefit of others.

In "gran fondos", although riders may only be competing against their own personal goals, they may find themselves sharing the same stretch of road with others, and some participants may wish to treat the event as a private race.

Steering control is severely compromised when using aero bars. They're not considered safe when riders may be racing in close proximity - a slight wobble could cause a major takedown. They're not great for cornering either. Hence the reason they're illegal in most events, except triathlon and time trials, where riders are mostly spread apart and riding fairly straight courses.


why change gear and brake cables? So people say you should change cables because of stretch. But after the cables have stretched, isn't it just easier and cheaper to adjust the cable and pull it a bit tighter?
Why do I need to replace the entire cable?

Cable stretch is mostly just things settling into place (ferrules into housing, housing into frame stops, housing compressing) rather than physical stretching of the cables, and after a week or so of installing new cables, you simply adjust them to the right tension. This is normal, as is periodic adjustments of cable tensions involved on your bicycle.

Replacing cables is done for a different reason than "cable stretch". A Bowden cable (see also here), such as the shift and brake cables used on a bicycle consists of an inner wire and housing. As the housing's lubrication wears away(*) or the cable rusts, the cable catches on the housing causing things like the brakes not releasing properly or sloppy shifting. Also, sometimes the cables (which are made of twisted wires) fray and break. If this happens on your brake cable, you don't have braking (which is bad!). Most shift cables fail safely by just forcing you to some extreme gear combination (rear is normally the smallest sprocket). Thus, it is advisable to replace your shift and brake cables periodically.

I have to replace my cables at least once every winter due to corrosion and road crud, for example, but I do have to do cable tension adjustments periodically when the cables are not replaced (such as indexing getting a bit sloppy or to account for my brake pads wearing down or something).

(*) Some people oil their cables. Most manufacturers now recommend against this.


Worth it carrying spare spokes? Truing a wheel and lacing spokes is a big deal, requires a truing stand and everything. I know some do it without tool just with the spoke wrench and the naked eye, but feels like a big deal to me.

When one breaks a spoke, I believe it is safe to say the wheel is out of true within a few meters.

The question therefore is: is it worth it carrying spare spokes when touring longer distances (200+ km)?

It's pretty easy/light to carry around a couple extra spokes per wheel and a pretty good idea for a long tour.  You'll probably need a few different lengths though for the front, rear left, and rear right sides.

Another good option is to carry an emergency fiberfix spoke that can be used with most wheels, which will help in an emergency.

http://www.amazon.com/FiberFix-Emergency-Spoke-Replacement-Kit/dp/B001GSMQZC

You may want to work on your skills with truing a wheel without a stand as well. You can use a couple zip ties on your seat stays in place of a truing stand. Just make sure you are comfortable with this process before you go on the road, and don't forget your spoke wrench.  You may need a cassette tool / chain whip as well if you need to replace a spoke on that side of the rear wheel.


What kind of bb is this? not sure what kind of bb mount this is for a crank? It’s like this on both sides

Probably ISIS splined. That’s the only one with splines of that length with the smooth end.
https://www.sheldonbrown.com/bbsize.html


How wide is a 2.2" MTB tire? I brought my MTB into reputable local bike shop to swap out a worn 5 year old tire.  Front and back had 2.2" tires that were actually 2.2" wide.  Mechanic says he has a new tire of the same kind ("Continental 29 Mountain King 2.2") in stock.  I was thinking to go wider but say ok and ask them to install.  New tire says "2.2" on the side, but installed and inflated it is 1.8" wide and visibly narrower than front.

Are tires sized like lumber, you take 0.5" off from nominal?

It otherwise seems fine, aggressive tread, etc.  Should I care?  Am I over thinking this?  I'm just a fitness XC rider on single track trails in all kinds of weather.

MTB tyre sizes are very variable, and the only way to be sure what size you will end up with is to read online reviews and/or see it mounted on a wheel in person.

mattnz is indeed correct in his comment that size can even vary between models from the same manufacturer.

The Conti Mountain King 2(and the XKing that shares the same carcass) in 2.2" flavour are well known to come up small and are generally considered to be a 2.0/2.1.  No need to be concerned though, as they are generally well thought of as XC tyres.

With these two tyres i'd be more concerned about getting the correct rubber variant of rubber compound (either the PureGrip or BlackChilli) than the true size of the tyre.


Do pedal-driven bicycles exist that can handle highway commutes? Do pedal-driven bi/tricycles exist which can be driven at highway speeds without fuel or electric drive assistance?

Assisted brakes, steering, lights, and amenities such as climate control or navigation are valid addons as long as the drive system is manually operated. Drive assistance must be limited to gearing (and perhaps flywheels.)

No.

The Tour De France currently has an average speed of about 40km/h, fasted speeds are a team time trial, about 58km/h over 25km. (Wikipedia), average cyclist would be with 1/2 those speeds, average person probably half again. These speeds, while impressive, are well below what I would consider "highway speeds", and the bikes they rode , while expensive enough to expect it as standard equipment rather than optional extra, certainly did not have climate control and power assisted steering

An elite athlete can output about 1000 Watts peak, 700W over 10 minutes, and sustain about 300Watts of power indefinitely.  A normal person half of that*

Climate control in a car requires about 3000W. A small car engine produces about 50000W, a super car engine, 500000W.
The more power you need to go faster climbs exponentially, so a cyclist maintaining say 30km/h needs 10 times the power to go 100km/h (and that seems light to me).

That is presuming all the extras weight nothing and do not increase rolling and aerodynamic losses, but lets argue that those are offset by technology that improves efficiency .

If you want to create a cycle that can cruise at highway speeds, with Climate control and power assisted everything, you will need to create a rider with a power output of about 10kW-20kW. At this time, society will have bigger problems than highway congestion and climate change - like feeding and controlling these 10kW humanoids.

*Actual number may be out by a factor of 10, but  does not change the disccusion.

Also: Note the recent drop in average Tour speed? When did the drug doping scandal happen? I'll let the reader decide.....


3% difference speed sensor vs GPS I'm using the Wahoo ELEMNT BOLT with RPM speed sensor. First few rides with my dad I noticed my measured distance was about 2-3% off from his, I used the standard 2.096m size of my wheel (700x23C). He uses the Polar V650 which measures it with GPS. When I let Strava recalculate the distance is also has this difference.

After this I started using the auto-calibrate feature but this error still holds, not much has changed. I also did a rollout test where my circumference come to be around 2.093m. This difference however only accounts towards a 100m difference in distance. Nowhere near the difference that the GPS units calculate.

Anyone of you have any experience with these kind of sensors and data discrepancy? GPS is quite trustworthy when looking at the total distance so I'm not sure what to trust.

It may not have to do with sensors or wheel diameter. My gf and I go on rides together both using Strava via phone app. Every time, without fail, the data will claim she rode about .15 per mile more than I, even though we stayed together during the ride. I've tried it with my Garmin and get similar results. I think GPS technology is just jankier than we perceive it to be. I have looked closely at some of the map data after rides and often, my path on the map looks like a squiggly line when I know I wasn't swerving THAT much. Gps is just not perfectly accurate. If your wheel and your dad's wheel are the same diameter and you get different results, this is probably why.


How do the wheels attach on this trike design? How do the wheels attach on this trike design?

Here are the design drawings.  If you go to the section titled Steering Bridge Components you can see were it should attach.

However it does not show the actual way it is attached.

Here is picture from the drawings of the steering bridge:

and here is the finished product:

The wheels are 24 inches with reinforced axels.

Here is an interesting look at wicycle using this type of wheel.

They have an "attacher piece as seen in the kit.  One axel, one wheel, and the attacher pieces.

How do the wheels attach?

The instructions never illustrate how the wheels attach to the frame so all we can do is guess.

Looking at the picture (the vehicle is facing left)

The wheel bolts to the steering rack - attaching something like a wheelchair wheel.
The there is a black verticle rod with a black ball on top on each side used to pivot the rack and steer the vehicle.

(The vehicle is facing right)

The wheel bolts to the end of the "steering bridge".
The only place I can see to attach a wheel has been marked in the picture above.

It would be wonderful if the instructions had illustrated the arrangement of the axle bolt, washers, and nuts.


Submitting road data to Google I have really enjoyed Google Maps cycling directions but find it lacking a lot where I live. I really want to update the maps with new/better information but I don't know the what, how, or where.

What data can I submit to update Google Maps cycling data?
What format does the data need to be in to submit it to Google Maps?
Where do I submit this data? (i.e. url)
How is the data submitted?

The easiest way to submit data is to right-click on the map and choose "Report a problem".  This pops up a small form with a marker.  You drag the marker where the problem is, and you pick a category and type something to explain the problem.  In a few days, a human being reads it and (assuming he/she agrees) fixes it.

For instance, Google Maps would send bicycle routes near my house to a road with a killer hill.  There's a reasonable alternate route that adds only about a quarter of a mile, but avoids the killer hill for a much more gentle hill.  So I reported it.

In a few days I got an e-mail that said "Your Google Maps problem report has been reviewed, and you were right! We'll update the map soon and email you when you can see the change."

Sometimes you'll also get an e-mail afterwards that says "Google Maps has been updated to correct the problem you reported. You can see the update here, and if you still see a problem, please tell us more about the issue:  (link)"

And now those same bicycle routes, by default, route along the gentle hill instead of the killer hill.


Torque Wrench required for trainer cassette installation? I have a new trainer arriving on the 29th and obviously this will involve either using my existing cassette that’s still on the wheel or a new cassette to put on the trainer.
As my existing cassette has already run the same distance as the existing chain I’m thinking of using the existing cassette.
Now removing and installing the cassette doesn’t seem too hard and I’ve ordered the relevant tools

Chain whip
Cassette tool

How important is a torque wrench on this?
I think I remember somewhere that the R7000 cassette is 40Nm, or roughly 29 ft-lbs.
Do I need a torque wrench or is it a case of being tight is good enough?
Looking at the trainer install video the guy literally does it up with an adjustable wrench. This got me wondering how important is a torque wrench in this instance?
Install Video
Skip to around 6 minutes for the cassette installation

How important is torque wrench on this?

It's not important at all.  The cassette lockring just has to be tight enough to not come off as it's not doing anything other than keeping the cassette from sliding off - some cassette lockrings are even make of aluminum.
Use a long wrench and put a bit of force behind it and you'll be fine.


Chainline calculation I need to replace my completely worn cheap cranks (not sure how those are called, but the chainring and right crank are one piece). The chainline of my singlespeed freewheel is approx. 43 mm. I have a brand new Sugino RD2 crankset lying about (listed as 45 mm chainline with ring in outer position when used in combination with a 103 mm JIS spindle). I pulled my left crank and it revealed a Campagnolo bottom bracket (looks like centaur or veloce). I measured the width of my bottom bracket frame tube (standard 68 mm) and the  spindle protrudes for 22 mm on the left side (measured from the edge of the bottom bracket tube), so I concluded that the spindle length is probably 111 mm.
First question, is that a safe guess? Or should I really pull the right crank too?
Quick inspection gave me confidence that the combination of the ISO bb and the JIS crank won't be a problem. According to the late Sheldon Brown, this would cause the chainring to sit 4.5 mm more inboard, so the combination should give me a chainline of 44 mm with ring in outer position. Is this right?

You're taking the right approach, although 2(34+22)=112. Measuring half of the spindle as you did is fine as long as you're 100% confident it's a symmetrical spindle. In practice it's something I might do with the knowledge I have to double check later and fix things if by chance they didn't work out.

Even if Sheldon's 4.5mm number is right on, this would give you 45mm front chainline, which would work despite not being ideal. Personally I don't know if it's just 4.5mm cut and dry like that in all cases. But it's probably worth a try.


Mountain bike tires for rocky, steep, dirt trails? I live in central Iowa and travel once a year to the Breck area (Breckenridge, CO) to do mountain biking. Since that is the Rocky Mountains, well they are rocky and steep. Very different terrain from the dirt top soil trails here in Iowa.

Anyone have some tires they would recommend for the trails out in Colorado? Btw, I ride a 29er.

It has been a while since I have been to Breckenridge, however, from what I remember of the terrain and trails it is 'rocky'. I am not sure that I would like to get caught out on punctures there - this will matter whether you are going into true back-country or finding your way around on resort cycle paths.

My recommendation is for the Specialized 'lightweight' 'Armadillo' tyres 'Captain Elite' - dual compound, nice and nobbly, good TPI casing, foldable - the wishlist boxes get ticked for where you are riding and what you plan to be doing (that'll mean no mud, then).

For the front you can put the 2.2" and on the back the 2.0", and in 29-er.

Anyway, I am quite envious - I wish I had got my act together and had the dream to head off to Colorado for cycling this summer! Enjoy, I am sure you will.


Where can I find the complete Tour de France routes? I fear this may not be fully on topic as I'm looking for some map data.

I would like to get the routes for all the stages of Tour de France for a particular year, ideally on Google Maps/Earth. Here's what I've tried so far:

Le Tour - Tour de Fance Official website
Tour de France Manche - Stage 1,2 and 3
VeloWire - first Tour de France 2016 stages in Google Maps/Google Earth
2travel2 - Tour de France 2016
CyclingStage - Tour de France 2016 stages 1, 2, 13

Some of these have Google Maps routes which is great, but that covers about 4 stages out of 21. Is there an online resource that has the routes for the other stages ?

Google Maps/Earth would be nice, but even a text based list of locations through which the Tour de Frances passes (rather than just start-end locations) for the stages would be useful.

The official website now has a list of all stages with links to (fairly small) maps, route profiles and estimated timings for various points on the route.


Is there excessive lubricant on my new rear derailleur? I just received a new Shimano Deore rear derailleur, which has large gobs of lubricant in two locations (one clearly visible in photo). This seems excessive.

Do I leave it, or are they expecting you to wipe the excess away before installing?

All of that goo is very typical of drivetrain components that are fresh from the factory. The factory uses a particularly thick lubricant to protect the parts until they're purchased or installed (lest they sit on a shelf and risk being exposed to moisture).

Basically, the factory is expecting whoever installs said drivetrain components to identify any excessive grease (some of it is there for good cause, such as protecting the inner spring from the elements), wipe it down, and re-lubricate with something lighter!


Broken rear axle. Why does it happen and is it worth trying to repair? So I'm taking the time during the holidays to overhaul my commuter bike. The whole drivetrain was full of old oil, road salt and grime so I decided to take the whole thing apart starting with the back wheel. Once I got it off, I ended up with half of the rear axle in my hand and a bunch of ball bearings on the floor (I found them all eventually).

The bike has been in use for about 18 months, and there were no rust and plenty of lube inside the hub so I don't really think it's natural wear.

What could have caused the axle to break? My theory is that they pulled the nuts too tight when they built the bike.

More importantly, is this a "user serviceable part" or do I need to get it repaired/replace the wheel? Seems to me getting the ball bearings to stay in place while I insert the axle would be quite challenging.

Most of times the axle is broken when not accurately jumping with bike (the same is with obstacles on road like holes and speed bumps). Wheels with freewheel are more exposed to this because their bearings (i.e. the place where wheel touching the axle) far from the place where the bike touch the wheel, therefor it have more moment to brake the axle.
To the question about worth repair. The only available repair of this - is to put a new axle, that means it will be like a new wheel (if you do not have other problems in your wheel). If you going to replace the axle, examine the bearings cup if it have any deformation. If it have, in most cases the wheel must be replaces. Examine also the cones.


How thin/worn out can you allow road bike rims to get? My mechanic measured the rim off my front wheel to be 0.8mm thick and recommended to get a new wheel. How thin can a rim get until it gets very dangerous to keep riding it?

0.8mm is very thin and dangerous. The mechanic is right to tell you to replace the rim! Keep it only if you want to play with your life because it may fail in a catastrophic manner! More dangerous even on a front wheel.

Many rims have wear indicators, usually a couple of holes along the braking surfaces, that tell you that the rim is over the limit once one of the holes becomes invisible.


Disadvantages of run 650B wheelset on a 29'er I am in need of a new wheel set for my 29'er, and wondering if 650B's are an option. My current bike handles more like a supertanker than a bike. Great for straight lines once up to speed, but if there is a corner, watch out...  The 650's are supposed to more responsive than the 29er and roll better than the 26". Additionally my wife rides a 650B, so we would be able to reduce pare tubes and tires.

Bike has disc brakes so that is not a problem.

Apart from lower BB, hence increased risk of pedal strike, if I were to put 650's on my bike, what disadvantages would I have.

But you don't know your bike would handle any better with 650.  In an earlier post you said you liked your  wife's bike.  Wheel size is not the only difference unless they are otherwise the same bikes.  Put your wife's wheels on your bike and try for yourself.  My 29er is better than my old 26 is every way.

The clearance is only 1/2 the difference so a change of about 2 cm. But 2 cm is enough to notice. Not just clearance you change geometry.  But that may be a good thing for your supertanker.

Also the weight of the wheel and tire will effect the performance.  Even how easily it turns Angular_momentum.  A lighter wheel and tire will be more nimble to turn.   A lighter 29er might give you (a bit) or what you are looking for.  In the end a different frame geometry may be what you need.  I think you are putting too much on wheel size alone.


Reattaching fork to mountain bike - What is the correct assembly order? I'm trying to reassemble my mountain bike fork making sure to put the bottom crown race and assorted pieces back together, but I can't quite figure it out:

Here are all the parts I have:

(click the images for full size)

Am I missing something? For some reason, these don't feel like they fit together correctly no matter which way I try it.

There are a number of different schemes for fork headsets, but this seems pretty close to what you have:

Here is a different image of an older design, but with the same basic components, and a little easier to understand.  What's called the "crown race" in the first image is called the "bottom cone" in the second.

And this link may help you understand things a bit better.


Should I dispose of my cheap bike or is it worthy to keep? I was given a bike that cost £150.  How can I tell if this bike is rubbish or not?

Depends on your definition of rubbish! If I were to guess it is probably all entry level components, unless they have been upgraded. That would be the first indicator. You can cross reference them by typing model numbers into Google.

However, before throwing it away I would recommend putting it up for sale, or even better if there is someone in need, why not dust it off, polish it up and donate it to the less fortunate!


Folding Bike Seat Post Replacement I have a folding bike (basically this Origin8 model) and the seat/seat post got stolen.

I haven't replaced a seat post before, but this is the only replacement post I could find, and I'm not sure what else I need besides a saddle.  It doesn't have any sort of mounting apparatus, so I'm not sure what kind of saddle I need or if I'm missing really important hardware.  Is there a specific seat I should be looking for or do I need to buy mounting hardware?

You want a separate saddle clamp, that clamps round the top of the post and the rails of a standard saddle, something like this.

See also http://sheldonbrown.com/saddles.html#seatpost

http://sheldonbrown.com/harris/seatposts.html (scroll down to 'Traditional "pipe type" seatposts, use with separate saddle clamp'.)


Rear Shock Size for Felt Virtue 1 2008 I have just bought a 2008 Felt Virtue 1 frame and have no idea of the size of shock I need. Measuring the eye-to-eye length, it looks like 185mm, but how can I work out the stroke length?

The spec page on BikePedia says the rear shock is "Fox Float R Air, 130mm travel" and the fork is "RockShox Recon 351 Air, 80 - 130mm adjustable travel".
Unfortunately it appears that Felt doesn't have information on bike previous to 2010 on their archive page.


Are CO2 cartridges feasable for use on fat bike tires? Are CO2 or other portable cartridge style devices feasible for use on fat bikes with tires 26x4.5" or greater? I know there are large 20g or 40g cylinders available?  If so, what sizes of cartridges would be appropriate?

Though, I'm sure it might be good to have a pump as a backup as well in case you run out of cartridges.

The short version: Yes, they are feasible.

The long version: You can do a minor adjustment of my answer in this question by changing the molar masses involved.

The molar mass of carbon dioxide is 44.01 g / mol. The ideal gas law says PV=nRT, where P is pressure, V is volume, R is the ideal gas constant and T is temperature (in an absolute scale, e.g. Kelvin). Rearranging terms and converting from mols to grams, we see (44.01 grams/mol)*PV/(RT) is the grams of carbon dioxide you need to achieve pressure P for a tire of volume V at temperature T.

Lets be crude about estimating the volume of a tire using a torus. The volume of a torus is V=(pi*r^2)(2*pi*R) where R is the major radius and r is the minor radius. Google will calculate it for you (and has a picture of what major and minor radius is). We'll use an estimate of 15.25 inches for the major radius and 2.25 inches for the minor radius giving 1524 cubic inches, or V=25 liters. Assume a temperature of T=293 K (room temperature) and asking for a pressure of 1 bar (14.5 PSI) gives 44.01*1.02 g which is about 45 grams. We'll also assume the volume of the tire is independent of the pressure (which is reasonable).

You can use this wolfram alpha link to play around with the numbers. Note that this calculation is linear in the pressure for fixed volume, so asking for half the pressure requires half the CO2.

Alternatively, rearranging the terms, if your cartridge has M grams of CO2, you can rearrange  (44.01g / mol) *PV/(RT) = M to see P = MRT/(44.01 g / mol * V). Thus, the pressure you can achieve changes linearly with the mass of CO2 you use provided temperature and volume remain fix.

So, if you want to go to up to around 14.5 PSI, carry a 45 g cartridge. A 20g cartridge will give you 14.5*(20/45) PSI = 6.4 PSI, and a 25 g cartridge will give you 14.5 * (25/45) = 8 PSI. 16g gives you 5.2 PSI, 14g gives you 4.5 PSI and two 16 g cartridges (i.e. 32 g) would give you 10 PSI.

Note that these numbers are a bit rough -- you might lose some pressure connecting the CO2 inflator, and we used an estimate of the tire volume. With more accurate numbers you can improve the estimates (and they should be quite good with a good estimate of the temperature, volume of tire). Overall though, I believe this calculation gives a bit overestimated amounts of CO2 required -- the volume is likely a bit smaller than the volume we used as an estimate.

But they should be good enough for determining the right size of CO2 cartridge to use.

Note that increasing temperature means you need less CO2 (while holding pressure and volume fixed). Increasing volume (i.e. using a bigger tire than what you calculated for) means more CO2 (while holding pressure and temperature fixed). Increasing pressure means you need more CO2 (while holding volume and temperature fixed).


Do belts on belt-drive bicycles stretch under load and spring back? Reputedly they don't stretch over their lifetime Does a belt on a belt-drive bicycle stretch under load and then elastically return?
The only current manufacturer I know (Gates Carbon Drive) claims the belt does not stretch over its useful lifetime, but my question is does it stretch under load and then return?
I have read some forum posts (can't find them now), that say they stretch under load, so are no good for power applications such as single-speed racing. This argument would not seem to hold up since Gates now have a single speed racing team and they've won some races.

Does anyone have any factual information or practical experience that can answer whether the belt stretches under load and elastically returns?

A related question is if there is some slight elasticity would that help prevent the damage that can be caused to internal hubs from changing gears under heavy load?

Everything stretches under load.  How much is the question.

The belt manufacturers should have technical data, including stress/strain graphs, modulus numbers, or other "hard" numbers.

But, generally speaking, carbon fiber and steel both have a modulus of around 200.  It's not clear now much carbon fiber is in the belts (and the cross-section area times the modulus effectively tells you how much stretch will occur), but when you consider the thinnest parts of a steel chain, and the fact that the pins will tend to flex in tension, it's probably comparable.

In any event, stretching should not be a concern so long as it's not sufficient to cause the belt to skip on the cog, or some other mechanical issue.


is a SRAM XX 1 crankset compatible with an XT 8000 BB can I put a SRAM XX 1 2x10 crankset into the BB of an XT 8000 (also 2x10)

Not at all. GXP cranks need a left bearing with a 22mm ID, not 24 like Shimano.


Choosing lights for my bike I recently bought a bike and I'm looking at getting some lights for riding at night. I live pretty well lit city so I would just want them to make me more visible to drivers. What kind of things should I look for when purchasing lights for my bike?

The main things to look for when purchasing new lights:

How bright are the lights? Can you see them for a few feet, a block, half a mile, etc?
What is the angle of visibility of the light? It does you no good if you can only see the light from one single point - you want to be sure your light can be seen from a wide range of angles, especially for your rear light.
What features are included? - Do you get multiple levels of brightness (for your front light) or different flashing modes (for your rear)? It's nice to have different flashing modes on your rear because it catches people's attention at lot quicker than a steady light.
How long do the lights' batteries last? You don't want to get caught out with a dead battery (trust me, it's not fun)
To go along with the above - rechargeable set or normal batteries? The rechargeable is a lot nicer IMO, because you don't have to worry about getting AA/AAAs every few weeks/months. However, it's a lot harder to bring or find backups if you're going to be out for quite a long time. If you go with AA/AAA's you can also use rechargeable versions, which would cut down on the cost if you use your lights often.
Price point - How much is your safety worth?
Theft/secturity - How often do you need to worry locking your bike up in an area where people can take / mess with your equipment? If it is quite often, you'll want to look into something that has a quick release from the light to the frame or rubber O-rings (those are fairly easy to take on/off often) - thanks Colin Newell


Am I using the crank extractor correctly? I have this X-Tools crank extractor:

  X-Tools crank extractor tool for removing standard Square Taper and ISIS type cranks.

Here's the end that pushes against the crank:

Here's my crank: (it's threaded on the inside, but there's also threading on the narrower bit further in behind the square opening, which my crank extractor pushes against but does not engage with those inner threads...)

I screw in the crank extractor like so:

Then I put an allen key into the crank extractor and try to turn it clockwise, but it's just not budging:

The inner bit of the extractor seems to be pushing correctly against the crank. But do I have the right tools for the job? Am I going about this correctly? Do I perhaps just need more torque than I'm getting off the allen key?

Follow-up

Well, I left what I thought were "dust protectors" off after working on this. During a cycle, my pedal fell off the bike. Here's are a couple of photos for more info:

What I thought were just dust protectors, which keep the pedal screwed in:

View of the spindle after pedal fell off:

The pedal that came off:

Now I have to get the pedal on the drive-side off, and will follow up.

I don't know about this this particular crank extractor, but the one I have came with two different end caps, one for ISIS/Octalink and one for square taper. Check that the end cap you are using fits inside the square hole in the crank, otherwise you will just strip the threads.

After you are sure you have the right tool, use more torque. If you have a piece of metal pipe at hand, use it for extra leverage, or get a longer wrench. Turning clockwise is correct.


Can I run Campagnolo 10 speed chainrings on 11 speed crank arms? I  have been using a Campagnolo Chorus 10 speed compact for a while. Recently  the thread insert for the pedals came out with my pedal while riding.   Just before this happened I had ordered new compact chainrings.
Can I take an 11 speed  crankset with 110 bolt pattern and put on the chainrings from the 10 speed  crankset and run it efficiently with my existing 10 speed?

I m trying to find a solution because I can't find replacement  crank arms for the 10 speed and I really want to stay with compact gearing.

If the hole-pattern matches, there is nothing technical why you shouldn't run those chain rings on your crank. The difference between 10s- and 11s-components is the outer width of the chain. It is a bit narrower to squeeze between the closer spaced sprockets on an 11s-cassette. Chains for 11-speed systems are around 5.4mm wide on the outside, vs. around 5.9mm wide for 10-speed ones. The inner width is the same (3/32 inches).

So your chain rings are effectively fully down- and upwards compatible with your crank, and your other 10s- and 11s-components.


Consequences of under-tight cassette ring? I have a torque wrench that goes up to 24 N⋅m but as far as I understand a cassette ring should be tightened to about 40 N⋅m. What is the consequence of tightening the cassette ring to 24 N⋅m instead of 40 N⋅m? Will it damage the bicycle or make the bicycle unsafe?

Assuming your cassette and freehub body are conventional, the cassette sits on a series of splines, and would be free to slide left/right if there were no locknut in the way.
Since the hole in the cassette will be larger than the diameter of the freehub body, a missing or loose lockring will allow the cassette to twist out of the vertical plane parallel with the rim.  Effectively this will vary the horizontal position of the teeth over each wheel rotation, more noticeably on the bigger cogs.
However as long as the lockring is done up sufficiently to not back itself out and also tight enough to stop the cassette moving relative to the freehub body, you'll be fine.

I've serviced bikes where the lockring has needed a cheater bar to undo, and others where the lockring was not even finger-tight.   These latter ones tended to have poor shifting and/or damage to the freehub body's splines.  Since finger-tight is under 3 Nm  ( okay 0.1~0.3 Nm or 1.7~2.6 Nm depending on what study you're comparing)  then 24 Nm from your torque wrench plus a yank more with a spanner should be close enough.
In full disclosure, I've never used a torque wrench when securing a cassette lockring (new or reused) and I've never had one come off or fail.  You develop a feel for a pressure that is tight enough for this application.

https://www.ors.org/Transactions/59/PS2--085/1535.html tests .1 to .3 Nm
https://en.wiktionary.org/wiki/finger_tight says 1.7~2.6 Nm


Why does my rear derailleur keep breaking? I upgraded my rear-mech with a new cassette, chain and new cables a few weeks ago since then i've mangled two rear mechs!

Both times I've just been riding along; not in a big gear; not at the extremes of the cassette, the mech just seems to get caught on something (the chain?) and bends and snaps!

I've got to buy a 3rd mech and I'm wondering why it's happening, is it just bad luck?

The mech I replaced (an ageing XTR) I'd had for years without any miss-hap but now I've mangled two XT mechs, one was a Shadow and the one prior to that was a standard.

Any sugggestions?

Did you change the chain after the first derailleur broke?  If the same chain was on and you're positive the derailleur didn't connect with the spokes, then the chain is a likely culprit.  Another thing to watch out for is loose pannier straps (or anything else that could get caught in the chain and take out the derailleur).


Is there any way to remove a rear cassette WITHOUT a cassette wrench? I've tried to and tried, but just can't do it. Can anyone help me with a way to remove my crappy old 7 speed cassette and install a brand new 11 speed without using a cassette wrench? I'm not rich enough to own one.

Use the correct tool.  There really is no other good answer.

Bodges that could get the old one off, maybe

a hammer and cold chisel - likely to upset the threads on the freehub.
a grinder and cutoff disk - guaranteed to damage the freehub, plus throws sparks and metal shavings into the mechanism.   I've actually done this to a cheap bike where all I needed to save were the spokes, and not the freewheel or hub.  Most enjoyable.
a gas axe/torch will definitely cut the lockring off, but you'll also damage the hub and spokes, and possibly the rim too.

Practical Alternatives

You need a cassette lockring removal tool.  As per comments they're a few dollars from China, or about 10x that from your local bike shop immediately.

Park FR-5, likely to last decades.

You will also need some way to hold the old cassette to undo the lockring.  The correct tool is a Chain Whip

Park SR-1, again expect 30 years service out of this tool.  It costs three times as much as the locknut tool.  I have managed to bodge this by using a length of worn old chain and a pair of vise-grips.

What can I do?

There exist Bicycle Co-operatives who exist to help you with your bike.  They're generally free or donation-if-you-can levels.  And they will have these basic tools for you to use, and may even run workshops.  For me locally, RAD (or Recycle-a-Dunger) is a good service, and can be found at http://www.radbikes.co.nz/

Another option is any kind of "mens shed" which are global, and tend to be populated by some very handy chaps.  Example  http://www.kinrossmensshed.org/what-we-do.html

A third option is to ask around anyone you know who cycles.  Worst that can happen is they say no.

Lastly, you might be able to take your (clean) wheel into your Local Bike Shop and ask for help.  If you're a customer, a LBS might be able to help by quickly slapping it through, for minimal or even no charge.


Please help identify my 1940's (?) Tandem Bicycle Please help me identify this tandem bicycle. Here's what I know:

I'm pretty sure it's not a Schwinn, as all Schwinn bikes had straight frames without curves.
From what I can tell, Hawthorne used the same skip-tooth sprocket on Hawthorne bikes until the early 1950s.
It has lines like a Colton, but I can't find out if Colton made a tandem that front steer only.
The serial number has been painted over/obscured.
Seats not original.
It has fenders, not shown.

(Not for sale at the moment.)

This is a little crazy but here goes.

I think it's the front of a Hawthorn men's bike

With a Hawthorne ladies bike wielded on for the back half

The rear stays of the men's bike are removed. The head tube on the ladies bike is removed, the top and bottom tubes are wielded to the seat tube on the men's bike. Both bikes have the correct skip tooth front sprockets.

The connecting tube between the "top" tube and the "bottom" tube on the ladies bike is no longer parallel with the ground on the tandem because the seat tube angle is not the same as the head tube angle.

An extra tube is wielded between the bottom brackets on the two bikes.

The ladies bike is listed as being a 1941. The men's bike is listed as "pre-war".

Here is a good discussion on dating a Hawthorn bike.

  Hawthorne used three different chain rings on their full size prewar balloon models, the ?snowflake? the ?speed-comet? and the ?torque-star? (my names). The torque-star chain ring didn?t appear until 1940 so if it is original to your bike that would date it to 1940-1942.


Winter riding: Is it safe to ride on a BSO/cheap bike at temperatures below -15°C on icy or damp roads? OK so I'm new to cycling and only own a road bike but I've been told that it's not suitable to ride in the winter in Canada. Winter here goes from -15°C to -35°C and there's plenty of ice and snow.

The only other spare bike I have is a BSO my parents bought for my birthday 2 years ago and I really want to keep cycling as a mean of commuting even in winter. I'll be mostly riding on flats for that matter and my average speed on my BSO in summer is 20km/h. (For a 15km trip)

I can only speak from my experience, as a winter rider in Norway (around the capital).

When the winter sets in I usually just end up putting more clothes on myself, and studded tires on my bike. I avoid hard biking (biking so that I get tired, breathing heavy) when it's below minus 10/15 degrees C, because breathing in such cold air can be damaging for your lungs.

Of course, with all the extra salt (at least in Norway) the bike parts get worn out faster, and I usually end up changing at least the chain after the winter, and maybe also the cassette. I have some friends that usually buy used cheap MTB and throw them away or sell them at the end of the winter season.

Edit: One other thing that is important, is to be visible. Depending on the road you're riding, you may share it with other cars or cyclist/runners/walkers. In Norway it is mandatory to have light (yellow in front, and red in back), plus a bell. In the winter I also use a safety vest (they may look silly, but it's not cool to be hit by a car!), plus a stronger light in front, than in the summer. Just be aware that the light should point down, so you don't blind other people.

I think the best solution is just to try it out, and take it easy. Wider studded tires will help you.

Also, be careful about sharp turns. They are dangerous in the snow/ice/winter.


What does the "c" in bicycle tire size mean? For instance, in some cases I will see a particular bike tire listed as available in 700x25, 700x25c, 700c x 25, and 700 x 25mm.  (Just picking out a number here, it could be 23, 25, 27, etc.)

What, if any, is the difference between these?  I would think that 700x25 is the same as 700 x 25mm, but I'm not so sure about the "c" when it lists both "700x25" and "700x25c" as sizes for the same tire on the same site, and lists different prices for each!

It doesn't mean anything, really. It's a historical relic.

At one point in time, "700c" was a standard tire/rim size, where "c" indicated the bead seat diameter and "700" was the diameter, in millimeters, when the tire was installed and inflated.

That "700c" tire size has a 622 millimeter bead seat diameter. There's an ISO standard that's often listed in small print where those tires are all '25-622'. This is the same as "29er", though usually tires marketed that way are substantially wider. "700", "622" and "29" are really all the same size.

All those tire sizes you list are the same.  If there were different prices for the "700x25" and the "700x25c", it's because there was some other difference between the tires, like model, threads per inch, bead type (wire or kevlar), etc...


How can I prevent theft of mirrors? I want to know to permanently fix back view mirrors. Last night, somebody stole them.
Please tell me any solution.

Make your bike less accessible.  Don't park it near where people walk past.  Instead, park it down the row a little.  Avoid parking it anywhere that will be in anyone's way—inconvenienced people may take it out on your bike.

Park your bike in a secure location if possible.  That means not leaving it outside overnight; ideally bring it into a lockable garage or shed, or even into your home.

Make the accessory securely attached.  That means no velcro, no quick releases, and no breakaway plastic.  A downside: breakaway parts are a safety feature to reduce the chance of stabbing into you or someone else.

Also, look at the fasteners.    If it's a thumbscrew like a GoPro, anyone can undo that without tools.  So look for replacement metal bolts that can be torqued down tighter.  Ideally the new metal bolts would be into metal fasteners—plastic ones may strip out easier.

To protect the bolt, you can use some weird security tool fitment that the thief won't be carrying on their person.   Or consider putting a blocker in, like a ball bearing into a hex socket.  You can retain it with candle wax or glue, annoying to remove legitimately.

Also prevent the bolt being removed by using a thread locker like locktite. Generic superglue/cyanoacrylate glue also works fairly well.  Avoid the threadlockers that need heat to release, else you can't get your own parts off without a hot torch which will melt other things.

An additional thought—depending on how your bike bars are set up, it may be reasonable to wrap your bartape over the accessory fitments.  This will obscure the fastener and make it take longer to interfere with your bike.

Naturally these suggestions won't make your bike theft-proof, just make it less-attractive and take longer to fiddle with.


Are folding handlebars a good idea from an engineering standpoint? A couple of Chinese stores have been selling folding handlebars:

At first glance this appears to be a great idea since the handlebar width is one of the reasons that carrying and storing bikes can be a problem.

From an engineering standpoint, are these types of handlebars feasible?

Well, from an engineering standpoint, no. It increases complexity, cost and weight. Those might be a deal breaker for the commuters who would likely use them. From a practical standpoint, maybe. @NL_Derek; you could be the first to test one!

In conjunction with other folding components (frame like a Dahon & pedals), it may suit the users need, imagine putting your bike in a suitcase.

If we assume that the design criteria are such that we need a folding handlebar, nothing here jumps out at me as anything that could not be adequately addressed with quality engineering. You could say a folding bike or folding pedals appear to be very dangerous, but if they are well engineered and manufactured with quality, there is nothing inherently dangerous about them. Whether this particular item is well made, can't say. @RoboKaren, I'd agree that something other than the threaded connection between the two halves might be better unless it has some measure preventing it from loosening unexpectedly, like a cam-lock mechanism of some sort.

Just for kicks, I modeled up what in my estimation would be a sturdy hinge assembly, if made with the right materials, roughly copying the design of what is shown in the picture. I don’t have time to do a joining detail though…


11/10 speed cassette remove 2 cogs to fit 9 speed hubs Is it possible to remove 2 gears in 11 speed cassette and fit to a 9 speed hub? or remove 1 gear in the case of 10 speed. my hub is Shimano WH-RS10 9 speed hub. My current cassette is sunrace 9 speed 11-28. I want to change it to a wider gear ratio and i am planning on using a 11 or 10 speed MTB (11-40) cassette then remove extra gears to fit on my 9 speed hub. My RD is sora GS,and i will also use roadlink to reach 11-40 set up. Thank you!

This will not work. The sprocket spacing decreases by about 0.5mm as the number of sprockets increases. The difference sounds small but you would get awful shifting and indexing problems at the largest and smallest gears.

BTW:  8, 9 an 10 speed cassettes all fit on the same width freehub body. 11 speed road gets slightly wider.

You'll have to look for a 9 speed cassette with the large sprockets you want. Beware you will get big jumps between gear ratios which could negate the benefit of the low gear ratios. Opinions expressed on this site about how well Roadlink or other hanger extenders work are varied,
so don't expect the setup to work well straight away.


Bicycle shoes for road cycling I mostly used conventional sneakers for cycling  and never wore bicycle shoes in my life. At this moment of my life I decided to level up a bit. I've built myself a road bike and now I'm looking into proper footwear. It's a whole new world for me and I'm completely lost. My first impression is that there are several types of pedals, cleats and shoes and you have to choose the right ones in order to fit them all together.

I'd really appreciate a brief consultation on how to choose a proper footwear gear. Which pedals play good with which shoes and/or cleats and how to buy the right combination?

Thanks guys! You're the best!!

Assuming that you're talking about cleats on your shoes, there are three main attachment systems.

Left: 2-bolt, Middle: 2 or 3 bolt, Right: 3 bolt.

Notice how the one on the left has a chunkier sole. The two-bolt option is used for SPD which are popular with MTB, commuting and touring cyclists. I use 2-bolt SPD shoes on my audax bike because I'm able to walk in them without slipping over or damaging the cleats.

A comparison of the different pedals has already been covered thoroughly on bicycles.SE, and Wiggle also provide some friendly explanations.


Sliding chain back on hub gear bikes I got a folding bike 2 months ago and got my first hiccup. It has a 3-speed hub gear and while changing gears today, it seems like the chain slipped off the smaller chainring near the back wheel into the gap with the wheel. As the chain is quite tight, my basic knowledge or Youtube info on how put chains back on in dérailleur bikes is useless.

How do you actually slide it back on? Is there a simple technique? I tried simply pedalling but it doesn't seem to make a difference.

If this matters, it's an S-RAM iMotion hub gear.

I also have a folding bike with a 3-speed hub (Shimano Nexus 3). My bike has a chain protection cover in the front chainring, so I find it harder to follow those other suggestions. I usually prefer to put the chain over the front sprocket in the first place.

The chain is also as tight as I can, but sometimes it happens that it falls over. I have noticed this happens when pedaling on a more irregular road or over bumps, so I just stop pedaling for a moment or go slower.

This trick is pretty easy and fast:

Grab the chain and put it over the rear sprocket (assuming it is already over the top of the front sprocket).
Because the chain is tight, probably, it will only be possible to move it over one or two teeth -- no problem.
Let the bike go backwards a little bit. The rear sprocket will spin together with the wheel and it will pull the chain over the sprocket.


Is it ever useful to use lubricating grease with EP additives anywhere on a bike? In the shops where I buy lubricating grease there are two main kinds:

Regular lubricating grease of semi transparent yellowish quality.
Lubricating grease with EP additives (Extreme Pressure additives) that is grey and not transparent.

Is it every useful to use the (EP) lubricant of the latter kind anywhere on a bike?

The simple answer is no, because loads, RPMs, and temperatures on bike bearings are all relatively low. Any of the common bearing greases are fine, and if the bike ever gets ridden in wet conditions then water resistance easily becomes the most important variable factor among greases.

Whether the drawbacks of any of the EP additives might ever come into play in any bicycle application I don't know. But using common moly EP lithium grease is fine.


Is going without a helmet more aerodynamic? Is having a bare head more aerodynamic than an aero road helmet?

I did not do exhaustive literature review, but the first hit, Aerodynamics of ribbed bicycle racing helmets has wind resistance measurements for several different aero helmets with vented helmet and bare head as controls. Bare head had similar air resistance to aero helmets at low yaw angles and the lowest resistance at large angles. The paper's conclusion is that for helmets (or bare head) that do not have huge number of vents, cross sectional area has more effect than the shape of the head or helmet.
This is of course purely academic, since competition outside sanctioned events doesn't count and in official competitions (excluding special cases such as hill climb time trials) you are required to wear a helmet anyway.


Which type of course is the fastest for a 10 km TT? A completely flat course or a course with 5 km uphill and 5 km downhill? There are two types of courses that I am considering for a 10 km trial:

Completely flat. 5 km out and 5 km back.
5 km uphill at a grade of 1%, and 5 km downhill on a grade of 1%.

Assuming you start and finish at the same place and the elevation increase/decrease is zeroed out, is one of these courses faster than the other? Or are they both the same? Would a lighter rider benefit from the 1% uphill gradient?

It is pretty obvious. Just imagine the hill rose a bit, say to 5%. And even more, to 10%. Going across a mountain is never fast. Mountainous race stages are slow. The total meters needed to be climbed over the stage count, not just the different between the start and the finish.
Do remember that the average speed is not averaged over the distance but over time. So if you spent more time in the slower section, it counts more. And you do, because you are, well, slower...
There is an old riddle. You have one hour to go to a certain place 10 km away and back. So you plan to go 20 km/h. But it was uphill on the way there and you only went half the planned speed. How fast do you have to go on the way back to get back in time?
I also notice you ask about a light rider. The more there is meters to be climbed per every kilometer of the course, the better for a light rider although the time trial discipline has its specifics and specialist riders.


Columba folder w/mountain 10sp cassette & Sram X7 derailleur On my bike the derailleur mounting bracket (hanger) is held by the hub axle and therefore fills some of the dropout slot on one side and pushes the axle lower in the slot on that side. So the axle is braced in its recess on that side, but not on the other side. This can cause the wheel to go crooked when I hit a bump and it's hard to get the quick-release skewer tight enough to prevent it.

To me it seems like a dummy dropout-filler is needed for the other side to balance the support the mounting bracket adds  -- or else a solid axle core that can bolt the wheel on tighter. Where can I get such a filler or what are my chances to convert the hub to a solid core axle?

That shouldn't be happening - it sounds as though you have the wrong hanger on the bike. If you have replaced the hanger (or a previous owner has) they have probably used one that fits on the bike but isn't correct. You may be able to file it down to fit, but it's better to buy the right hanger.

For your second question, it's definitely possible to swap out a QR axle for a solid one. The threaded part of the axle is the same for both, so it's just a matter of getting a solid rear axle and swapping the bearing races and so on over.

If you get that done at a bike shop they will probably suggest replacing the cones and bearings, since those are fairly cheap parts and the labour cost of taking the wheel apart is most of the cost of that swap. Once they have it apart if there's any visible wear it's worth doing, and unless the bike is fairly new I'd suggesting doing it. It should add less than $20 to the total cost.


Fork light mount on road brake pivot bolt - safe? Is it safe to put the front light mount designed for the fork (as pictured below) on the road brake pivot bolt?

I know I'd need a longer recessed nut. What makes me worry is that the steel wire loop of the mount is not flat.

I believe it is safe, as the brake's actuation isn't predicated on a flush mounting surface.  The problems you are likely to run into are:

Finding a longer recessed nut.  They only make those in a couple sizes, and you really should have them threaded on quite a bit to be sure they are secure.  You're screwing with your ability to stop here, after all.
Moving the brake ~2mm forward may change the brake pad position relative to the rim.  Just a tiny bit, but it may be enough if you were already at the edge of the brake's ability to reach the rim.

If both of those seem OK and secure, I'd say go for it.


What are early signs of failure in forks/stem/handlebars? I ride an SE Lager. In the past year, the following components have worn out or broken

Front chainring
Rear cog
Rear freewheel
Chain
Seat (one of the bars snapped off)
Many, many spokes
Wheels

Basically, it seems to be a very cheap bike made to a minimum standard. I like the feel of the bike and with my replacements for the above components I'm pretty happy with the way it rides.

The thing that scares me is that the forks, stem or bars will break and pitch me face first into the road.

How can I tell if these components are also weak or try to detect early signs of failure?

Update: Added wheels as replaced parts

You are well past the point where I would have told you to throw the bike away and buy a decent one. But IME the frame and fork are usually better built than the components on a bottom-of-the-range bike. There's no real corners to cut on a frame and fork, where they can shave component quality endlessly. Well, they can switch to mild steel tubing but that's rare above the $199 price point. You may well find that the only difference between your bike frame and one on a bike twice the price is the paint.

There's no non-destructive way to tell whether the frame and fork will fail that doesn't cost (a lot) more than the bike is worth. Especially since in this case the bike is worth less than the sum of its parts(1). You could try pulling on the frame/fork to see how flexible it is, but that tells you nothing about how likely it is to fail suddenly (unless it fails while you're testing it). Or you could xray it and have a competant metallurgist examine the images for defects (a single rock climbing carabiner can be thus inspected for perhaps $US200, but a bike is a lot more complex).

If you like the feel of the bike try looking for something similar, probably from the same manufacturer. But looking at their site, you have the mid-range model. I suggest test riding better bikes until you find one you like the feel of. Or do what you have done - replace everything on the bike with better components and hope for the best.

(1) you have replaced most of the components with ones bought retail. So you've paid more markup (and probably labour charges too) than if you had bought a bike with those components already on it. You're probably also suffering from the sunk cost fallacy - you've spent all this money and are reluctant to throw it away. I can't make that call for you, but look at what's left of the original bike and work out how much it will cost to replace it all - especially the wheels. It might be cheaper to buy a better bike and strip the current one for spares.


How can I protect components from being stolen off my bike? I had my bike locked up properly so that the frame and wheels were secure, but somebody stole the 8 speed and handlebars off of my bike. I don't understand how this can have more than a $10 resale value.

The bike is a Shimano 8-speed. They cut the tension cord in 2 spots... i'm not sure why they cut it near the derailer....

Is there any way to protect the gears? It looks like the other one that remains is susceptible to just an allen wrench and wire cutters...

There's no way to 100% secure everything, but there are things you can do to make it more difficult or time-consuming.

Don't lock up your bike. Bring your bike with you instead of leaving it outside. Mine goes into my office.
Choose a location where you or other people will see thieves messing with the bike. Not a super-high traffic area (in that case everybody assumes somebody else will do something), but a moderate traffic area. A thief will be more reluctant to do something obviously shady if there's people that might stop them. When I'm at a cafe, pub or restaurant, I try to lock up where I can see the bike from inside. Or use bike lockers of some sort where it's hard for thieves to get to any of the parts.
Use locking skewers such as pitlock or pinhead. There are a lot of variations on the concept, but the ones I've seen can secure wheels (via skewers), seat post (seatpost collar), fork (headset cap) or some brakes. A locking skewer would protect the casette from being removed, but not the rear derailer.
Replace the bolts with unusual bolts. Bike thieves are likely have a variety of sizes of allen wrenches (possibly in a single multitool) and maybe a T25 Torx (commonly used for disc-brakes). Also Phillips and flat-head. But they're unlikely to have other sizes of Torx or other more unusual types of bolts. Getting proper "tamper-resistant" bolts is difficult unless it's something like the pitlock stuff.
Mess with the bolts so that they're harder to undo.  One technique I've heard of is to put a ball bearing into the hex head and melt some wax/paraffin into it. Tilt the bolt, heat it with a small flame and the wax runs out. Or a bit of time prying and scraping with a small screwdriver.

Personally, I do #1 and #2, and have considered investing in #3.  #3, #4 and #5 all make your bike harder to work on, but at least #3 bike shops are used to and you just make sure to bring the special tool with you all the time.


Is it worth to get a Bianchi Caurus 909 and rebuild some parts? I'm planning to get a Bianchi Caurus 909 2nd hand for city bike and some long rides (30 km average) whenever i want to visit another city for example. The thing is if it worths to get the bike and change the gears, maybe the brakes, handlebar plus the maintenance. I've asked a bicycle guy from my city and he said it would cost something like 80 euros to clean and change its parts that i've mentioned on top.

I'd like to convert this:

To this:

Thanks!

From economical standpoint, rebuilding bicycles is almost always unreasonable. For the same amount of money spent on replacement components, it is often possible to buy a new decent bicycle of the same or better level, thus saving workshop time.

If, however, money is not a deciding factor for starting a rebuild, then the answer depends on whether you like spending your time with bike tinkering, and have no other better/enjoyable things to do. If you do enjoy working on your bikes, restoring old things, or want to learn new skills and things, then go for it — wrenching on a bike is often a rewarding experience.


Why does the glue in a puncture repair kit dry up so quickly? With puncture repair kits, generally you get like 6-8 patches and a tube of glue.

The only problem is I can really only use the glue for the first patch because once it opens, it just ends up drying up. Am I putting the lids on wrong or something?

I have plenty of the patches left. It's pretty much the glue that makes me keep having to buy more kits. Why do puncture repair kits only have one tube of glue? Is there anywhere where I can buy just the glue in bulk?

In my experience:

You only need to apply a drop of glue a bit larger than a pea (about 7mm diameter) per patch;
Glue inside eventually dries. If you only have a puncture once a year, most probably the glue remaining from the last puncture would be dry "no matter what". Also, there is an expiration date of around two years, but I think it's two years if you didn't open it yet;
(IMPORTANT) When you attach the cover of the tube, BE SURE TO REMOVE ALL THE AIR INSIDE by pressing its bottom untill half a drop shows up in the opening, otherwise the glue will evaporate inside the very tube (happened to me a lot of times until I figured it out...).
These glues have a volatile nature. I wouldn't buy it in large amounts, but rather to buy new spare glue tubes (without the whole patch kit). The kind of patch I use also have this problem: the patches (a small roll I have to cut with a scissor) last much longer than the glue.

Well, hope it helps!


Why is my average speed so low? I recently bought a bike (never rode one real one before, only ever used the gym ones) and became quite comfortable with it so I ride it everyday around my city.

Here's the thing, I'm a 19 year old girl (if that's relevant) and I exercise almost daily (plus the cycling) so my leg muscles are fairly strong, but my average cycling speed never got over 8 km/h, I was wondering why? Does the bike use muscles I usually wouldn't train?

My city is uphill/downhill almost no flat terrain, but when I looked up even average cycling speed for uphill it was 12 km/h, am I doing something wrong?

Average speed depends a lot on various factors.  But, having said that, 8km/h is very slow for a fit young person: it's not a whole lot more than walking pace.

Where you're cycling. In cities, it can be hard to cycle quickly. Cycle paths often have lots of pedestrians on them; roads often have lots of junctions, stop signs and traffic lights. If you're constantly having to stop and get going again, that will bring your average speed down a lot.

You say you're in a hilly city.  Going up-hill is, of course, slower.  However, on average, you'll go down as many hills as you go up, so that should balance out to some extent. If you mean that you average 8km/h up the hills, that might not be at all bad, depending on how steep the hills are!

How you measure speed. If you just compute distance travelled divided by time taken, then you're including all the time you're stopped in your average: if you cycle at 15km/h for ten minutes and spend five minutes stopped, your overall average would be 10km/h but, when you were actually cyling, you were doing 15. If you're using a cycle computer or GPS app, you should set it up to only compute average speed over the time you're actually moving.

How you cycle. Obviously, if you don't try to cycle fast, you won't be fast. Are you working quite hard when you cycle, or are you just drifting along? Do you get out of breath? Are you using your gears properly? A lot of beginner cyclists turn the pedals very slowly in much too difficult a gear, and it's hard to go fast that way (and very hard to accelerate away from a stop). As a rough guide, if you're pedalling at less than 60rpm on flat ground (i.e., pressing your right leg down once every second), you're pedalling very slowly and you should probably aim for something more like 75. Use an easier gear to compensate and, crucially, if you feel yourself slowing down, change into an easier gear. The point of the gears is that they let you keep the pedals spinning at a good rate whatever speed you're actually going at.  A good way to measure how fast you're pedalling is to use the internet to find out how many beats per minute there are in some songs you know, and compare that against how often you're pressing down your right leg.

How well your bike is set up and maintained. Many beginners have their saddle much too low. An easy rule of thumb is that, when you're sat on the saddle with your foot on the pedal at its lowest point, that leg should be almost straight. If your saddle is much lower than that, it's really hard to generate any power. Is your bike well maintained? Do the wheels spin freely? Are the brakes rubbing? Is the chain properly lubricated? Does the bike make noises while you cycle?


Disk Brake or V Brake I am willing to buy a new mtb.But i am totally confused about which brake to choose.I want to do daily communication by my mtb. and also often want to do stunts.in this circumstances which kind of brake is best for me???

Disk brakes hands down. V-brakes are difficult to adjust, can get misaligned and destroy tire and rim (happens to me, very quickly). Disk brakes allows you to change your wheels easily and works even when wet and muddy. With v-brakes you always have the problem of different pad-to-rim separation for left and right pads due to differences in springs tension. Disk brakes works even if your wheel is wobbly.

For me, disk brakes (and overall weight) were the main reason for switching from supermarket steel MTB to a real aluminum MTB costing 4x more.


Regreasing pressfit bottom bracket I strongly suspect there's creaking coming from my pressfit BB on a road bike.

What I don't know is whether the pressfit BBs is reuseable, so once I remove and regrease the whole thing in there, can I use the same BB again and put it in?

Unlikely that the creak is in the bearings themselves due to needing re-greasing. It's probably at the press fit interface between the outer race and the frame.

Yes you can remove and refit the bearing units. If the BB shell is metal you can use grease or retaining compound to try to stop the creak.

Global Cycling network did a video on BB creak recently.


DIY: what material to use as DIY shim seat post? Seat tube shim adapters are quite expensive, what kind of material do you recommend as a shim?

I have seen in a thread some guys talking about home made shim:

paper tape
alloy drink can as a shim (aluminium or steel?)
Thin and quality paper/cardboard

Which one would be the best?

Definitely alloy drink can or other thin sheet metal as it is not compressible and is not affected by water, oil or grease.


Is there a left-sided powermeter that requires less than 8 millimeters of clearance? I'm willing to spend some money on a powermeter to train a tad more effectively on my bike. The problem is, that my frame (Trek Checkpoint ALR 4 2018) does not have the required clearance between crank and chain stay of 10 millimeters.
Ideally I'm looking for a crank, that requires less then 8 millimeters clearance.
Alternative solutions would be a right-sided solution for a Tiagra group set or SPD pedals - given they do not exceed 500-700€.
I've been looking at solutions from Stages and 4iii, but none of those will fit. The SRM X-Power SPD pedals cost almost as much as my bike, so they are absolutely out of the equation.

The Checkpoint is a gravel frame, and that particular model has a road groupset. Unfortunately, while not all gravel frames have this clearance problem, this does illustrate part of the rational for the slightly wider chainline on gravel-specific groups.
I would strongly urge you not to get a right-sided power meter based on a Shimano crankarm. It's been shown that because of the way the spider is shaped asymmetrically, drive-side meters on the current generation of Shimano cranksets (e.g. R7000, R8000, R9100) are inaccurate. The problem is not present on the non-drive side, but that's the side you don't have space for.
Given that and your cost limitations, it may be difficult to get a new functioning power meter within your budget. The lowest cost pedal-based meter that I know of is IQ2, but they are not yet shipping widely, they had to redesign their product completely once, and they have had numerous production delays. See my comment on your main question. A good crank-based solution would very likely involve a new bottom bracket, since many of these use 30mm spindles, and your Shimano group is based around a 24mm spindle. (An exception: Rotor makes some cranks with 24mm spindles, and Power2Max sells power meters with Rotor cranks, but these tend to be expensive and may be out of your total budget.) You could also try looking for a used power meter; to my knowledge, drive-side power meters based on the last generation of Shimano cranks are still reasonably accurate (see the GP Lama post that I linked earlier).
Used power meters are worth considering, but I would investigage the reliability history of the particular model if possible. To my memory, the second generation of the Stages units and the second generation of Garmin's Vector power meter pedals (neither of which apply to you, unfortunately; the Vectors are Look road pedals) were less reliable than their successors. Quarq spider-based units have generally been very reliable, but DZeros made before about 2018 could, in some cases, get irreparably damaged if they were subjected to a side strike, such as from a dropped chain (I was one of the victims on that thread). Quarq covered those of us under warranty for that failure mode, but you would not have this recourse. I had neglected to mention this earlier, but Powertap appears to have offered a disc brake power meter hub. You would be locked in to the rim it comes with, unless you chose to replace it, and you would want to verify that the hub either has a thru axle fitting or that SRAM (which owns and has now discontinued Powertap) or a dealer is willing to sell you the thru axle endcaps.
Train without power?
One thought is that you could do without a power meter. It's true that structured training with power can enable pretty substantial gains, but it also takes time and effort to select, learn, and adhere to a structured training regimen. Moreover, in the absence of a power meter, you can do unstructured but purposeful training. Ned Overend described this approach in the first part of this Velonews podcast. He tracked his time on various known segments, e.g. climbs, and he just made sure to do a variety of efforts of various durations, plus get enough rest. You can use Strava for tracking segment times, and it will also estimate your power in the absence of a power meter (making a large number of simplifying assumptions, so it's not a substitute for real power, but it is actually reasonably accurate on average). Hence, you'll only need a GPS head unit, which you would have needed for your power meter anyway. The term I used earlier is not a formal term, and I don't believe there's one for it. It's a bit more structured than the advice "ride lots", a quote from Eddy Merckx when asked about what advice he'd give to aspiring riders. This approach is perhaps akin to fartlek workouts in running.
You could also train with heart rate. When you do decide to upgrade to power, many structured programs also incorporate heart rate data to gauge your freshness, so a heart rate monitor purchase wouldn't be wasted. For example, Strava will display freshness information to premium subscribers, and that requires either heart rate or for you to enter perceived exertion on every ride. For heart rate, one thing to know is that it's a lagging indicator of effort. Once you start a hard interval, it takes your heart several seconds to catch up. It's not as good for short hard intervals. And heart rate is also influenced by fatigue, so you still need to listen to your body; if you are having a hard time getting into the prescribed heart rate zone, you may want to take an easy day (but that principle also applies to power-based training). It's likely that heart rate is better for longer duration intervals. However, if you are riding gravel, those are the type of intervals you want to concentrate on. You could supplement longer intervals with shorter, unstructured sprints, or do an occasional day of short hill repeats to get your top end speed built up.


3x8 to 1x8 (with expansion to 1x10/1x11 in the future) I plan on converting my MTB fron 3x8 to 1x8.

I plan on leaving the rear derailleur as it is, or I would prefer not to upgrade it to save money.

My current crankset is a 3x8 square taper crank, I have yet to measure the bottom bracket but it'll be probably a 68 or a 73 shell, with standard  BSA/ISO threading.

Part list installed:

Crankset:

https://www.paul-lange.de/shop/de/shimano/alivio-acera-altus-7-8-fach/kurbelgarnitur-altus-trekking-fc-m311-vierkant-78-fach.html

Bottom Bracket:

https://www.paul-lange.de/shop/de/shimano/innenlager/innenlager-bb-un26-vierkant-bsa.html

Part list to purchase:

https://www.bike24.de/1.php?content=8;product=164399;menu=1000,2,88;mid[70]=1;pgc[7296][7301]=1;orderby=2

https://www.bike24.de/1.php?content=8;product=7192;menu=1000,2,81;mid[77]=1;mid[282]=1;mid[170]=1;pgc[10624][10627]=1;orderby=2

My question's/troubles:

BSA threading is universal/standardized right ?

If I purchase a 1x10 crank or a  1x11 crank for example I could install it on 1x8 setup right ?

What compatability issues should  I look out for ?

Are the listed parts compatible with each other ?

It's unclear if you mean versus other standards, or if there are
different kinds of BSC/ISO (BSA is kind of a misnomer, and in
my opinion it's clearer just to call it all ISO, because that's the
standard that current examples are actually made to). Some road
bikes are still made with Italian, but only a couple brands, and
bottom brackets can still be had for all the old national sizes.
Other than that, yes ISO is the only threaded standard left. Each ISO
BB is made for a certain shell width, or widths in the case of the common 68/73/e-type ones that come with 2.5mm spacers you use as needed, but there aren't shell
interface differences within ISO beyond that.
Yes, no problem.
Chain retention tends to be acceptable with just a narrow-wide ring and nothing else helping it, but it's something I'd be looking at when test riding the new setup. Of all the many rear derailers in the world, you could probably come up with some that didn't pull on the chain adequately. It's also good practice to start a new chainring out with at least a new chain and ideally also a new cassette. (This is now less true of the cassette since suddenly it's much more common for people to have extremely expensive ones.) You could skimp on it if they're still pretty fresh, but the idea is that minimizing wear on the ring tends to save more money ultimately. Worn chains can bring a new chainring to their level of wear fairly rapidly.

Chainline is also something one should look at when putting a 1x or
any other drivetrain together, although it's perennially overlooked
and so parts manufacturers do what they can to make it work out okay
passively. Buying a dedicated 1x mountain crank with 49mm chainline
such as the one you link to and putting it on a normal 135 8/9/10
rear (which wants a chainline somewhere around there) puts you in the camp of not
having to worry about it. Other setups create some hoops to jump
through.

Yes, presuming you get the correct version of the BB. (The BSA 68/73 unless it's got an 83 or 100mm shell.) You need an external BB cup tool.


Shimano compatibilty problem I have a hybrid bike which has dropped handlebars with Shimano Tiagra dual brake/gear levers.
The front mech is a Tiagra triple ring and the back mech is Shimano Deore XT (9 sprockets)
I have developed back problems and now need a more upright position when riding and am hoping to convert my bike to a flatbar.
Can anyone help in identifying the options for compatible Gear Shifters.
Thanks in advance

As long as your choosing a 9 speed Shimano shifter for the rear and triple shifter for the front you'll be fine. That's basically everything in the Deore lineup, as long as it's 9 speed. Obviously you'll want to stay away from 10 speed shifters and dont try to mix and match Shimano derailleurs and SRAM shifters or vice versa.
Though you didn't ask this, what may be a more important concern is how your bike is going to fit when you slap flat bars on it. Road bike frames are shorter in the effective top tube than mountain bikes are due to the fact that a straight handlebar decreases reach compared to a drop bar. Your bike is going to fit pretty darned short if you do a flat bar conversion which can cause comfort problems of it's own. There are other fit issues to be considered when doing a flat bar conversion on a road bike, but in my opinion this is the big one.


What can I do to be sure I'm getting a fair deal when buying a used bike? I've been looking at used bikes but I'm worried that I will get taken advantage of because I don't know a lot about bikes. Are there key questions or things I should look for when shopping for a used bike?

With any bike the most important thing is "fit" -- is the bike too tall, too short, too much "reach", too little?
For a bike to have a good basic fit you should be able to stand over it flat-footed and have "comfortable" clearance at the crotch.  For bikes with lower than normal top bars (eg, many mountain bikes), you should pick a bike that would be comfortable even with the top bar at the "normal" height.  And for "real" off-roading you want more actual crotch clearance than for more normal riding.  But too much crotch clearance is a signal that the bike may be too small for you.
The bike should also be tall enough that you can raise the seat high enough to have your legs nearly completely extended at the bottom of your pedal stroke.
When riding, the "reach" should be comfortable for your style of riding.  For casual riding you want a shorter reach and more upright posture than for racing or aggressive off-roading.  However, for really tall, long-torso people a "casual" reach can be too short for even casual riding, forcing the rider to curl his torso too much, and short people, on the other hand, may have to use a bike that's a hair smaller than ideal to get the most comfortable reach.
When you ride it is it stable (but is it also responsive -- there's a trade-off).  And obviously you want a bike that suits your needs -- multispeed or not?  "Road" vs "mountain"?  Upright or "aero"?  Can carry a load with a rack, or is stripped-down for lightness and speed?
Checking the bike over:
Everything should be parallel (except, perhaps, the chain on a derailleur bike).
Stand straddling the front wheel looking toward the back of the bike.  With the front wheel centered you should be able to look down and see the tire "disappear" under the frame tubes, with it not peeking out more on one side vs the other (which would indicate a warped frame).  Similarly, the front and rear wheels should be exactly in line, not one more to one side than the other.
Look at the derailer.  When the arm of the derailer is moved it should stay parallel to the wheel.  Look at the chainrings.  When the crank is turned, the chainrings shouldn't wobble.
Standing over the top bar, grip the rear brakes and move the bike forward and back.  There will be some "spring" in rim brakes, but there should be no "rattle" sensation.  Do the same with the front, only also feel for any looseness in the headset bearings.  There should be no detectable looseness in the headset.
Off the bike (and preferably with the bike upside down or suspended in a stand) shake the wheels, feeling for any looseness in the wheel bearings.  Likewise shake the crank.
And, obviously, check for serious rust, things that are seriously dinged, scratched, etc.  A few scratches on a well-used steel frame is not a reason to reject the bike, though (unless you're looking for a "perfect" specimen).


Is Nike Hindsight glasses only a concept or there are a real similar products? I came across the following issue - 'Nike' Hindsight concept glasses increase peripheral vision.

By the time of its publishing, these glasses were only a concept. My Question: is there a similar real working product in production?

The Hindsight glasses include fresnel lenses that widen the peripheral field, at the cost of increased distortion. As stated in the article, this is a design concept, so there's no guarantee it will ever make it to market. And although it's a neat idea, it would take a lot of testing to determine whether the tradeoffs are worth it for enough people.

This isn't the only example of fresnel glasses being used in eyewear. Peripheral prism glasses have been used in research for how to improve the vision of patients with hemianopia (blindness in half of the visual field), but although this is a related concept, it requires a completely different design.

In summary, no, fresnel lenses to extend peripheral vision are not readily available in cycling glasses.


Can I use a Brompton bike with a trailer like the Thule Chariot Cougar? I wonder if I can use a Brompton bike with a trailer like the Thule Chariot Cougar? It uses the so called Thule Axle Mount and I wonder if it is compatible to the bike. At this point, it is just advanced planning and I can't test the possible setup. What do you think, any experiences?

I'm going to say yes based on this photo.  It looks that the hole is big enough to pass over just about any axle, quick release or nutted.  I think what is throwing you off is that it comes with a quick release skewer that is longer than what is typically used for wheels.  You may not need that provided skewer.  Burley uses a similar one and I was able to put the hitch on a Jamis bike using the skewers that came with the bike.

If your bike has the internal gear hub, it probably has anti rotation washer (special washers to keep the axle from turning).  This hitch would mount to the outside of that washer.