Make rim braking efficient I have rim brakes on my bike both rear and front, but have been lately decreasing in efficiency, making weird noise when I brake hard and the braking distance has increased too.

Neither my brakes nor my rim have any problems like wear, tension, gap and such. I clean off dust from the rims every now and then. Any ideas what might be contributing to the decreased efficiency of my brakes?

I would look for contamination of the pads and wheels. Oil residue from the roadway may have gotten on to the brake surfaces. Try to clean them with a mild cleaner. I typically use the blue glass cleaner. If the brake pads are several years old they may be getting dried out or glazed. You can try to resurface the rubber face of the pad with a file. The improvement if any tends to be short lived. Avoid sanding the pads with sandpaper as the grit can imbed in the pad and damage the rim. Also consider some performance oriented brake pads. The pad materials have different characteristics such as wet stopping, dry stopping, durability and price.


Can I ride on the beach with 32c tires? I have a hybrid bike (Merida Speeder 200) with 700x32c tires.
I've been using it on the road with great pleasure, but given the corona situation it's becoming quite crowded on the (nice) roads.
Therefore I'm looking for alternative paths. The beach is semi-nearby and has a wide flat strip of "hard" sand during low tide.
Can I ride on the hard sand with 32c tires?

While my initial attempt with lightly deflated tires was not a success (I could only bike 100 m before being exhausted) my second attempt went much better.
Based on your helpful answers, comments and suggestions I deflated my rear tire to 1.5 bar, and my front tire to 2 bar and rode at the waterline without much problems at an average speed of 20 km/h.
I was there 1.5 hours after low tide, but there was still plenty of compact sand. Also, it didn't really matter if I was riding on the wet sand at the edge of the water, or a few meters further inland on the drier compact sand, both required approximately the same perceived effort.
Loosened sand (e.g. after dogs have played there) and swathes of shells/seaweed required more effort, so I tried to avoid those.
For context: I use Continental Grand Prix 4 Season 700x32c tires, weigh around 80 kg and am not superfit, but can sustain 25-30 km/h on the road.
Conclusion
Based on my experience: yes, you can ride on the beach with 32c tires if:

You deflate your tires significantly (to 1.5 - 2 bar)
Ride during low tide on the compact sand


Frame that takes 700x35 I'm looking for a new frame. My only requisite is that the frame should be able to take 700x35 wheels (the type of wheel I want).

How can I know if a frame is suitable or not for these kind of wheels?

When you buy a frame, they state the wheel type (it should have the right hub spacing for frame, braking surface (disc/rim brake) and rim size for the type of wheel the frame was intended to run and the size of tire you are intending to run) and tire clearance with it. Note that the tread pattern also affects clearance - if you have very aggressive tread or studded tires, you may not be able to fit the tire even if its the size they state. If its not stated, all you can do is get the frame and test a wheel+tire combination you want to use (your LBS will be helpful for this).

Some brands are known to have big clearance for tires, such as Surly (they market it as "FFF" - Fatties fit fine). Generally, the type of bike also affects clearance (fat bikes > mountain bikes > touring road bikes or cross bikes > road racers, for example). Most road racers won't clear a 700x35 tire, but most touring bikes and cross bikes will have no problem. A lot of 700c hybrids will also fit the 700x35 tire size, so the types of bikes which fit this tire size are pretty wide.


Why would one ever buy a 12-25 cassette when an 11-25 is available? I was looking at purchasing a new cassette and chain. Looking at the available cassettes for SRAM components, there is a big variety of sizes available:

11-23: 11-12-13-14-15-16-17-19-21-23
11-25: 11-12-13-14-15-17-19-21-23-25
11-26: 11-12-13-14-15-17-19-21-23-26
11-28: 11-12-13-14-15-17-19-22-25-28
11-32: 11-12-13-15-17-19-22-25-28-32
12-25: 12-13-14-15-16-17-19-21-23-25
12-26: 12-13-14-15-16-17-19-21-23-26
12-27: 12-13-14-15-16-17-19-21-24-27
12-28: 12-13-14-15-16-17-19-22-25-28
12-32: 12-13-14-15-17-19-22-25-28-32

Now I can understand why someone would choose a cassette based off of how many teeth the big gear has. Some people live in hilly or mountainous areas and desire a higher number of teeth. Some people live in flat areas where they simply won't use those cassettes with a lot of teeth on the big gear.

But why would anyone ever choose to buy a cassette with 12 teeth on the small gear instead of 11? 11 teeth = higher maximum speed. I doubt many people buying a nice set of components (Shimano, SRAM etc) would ever say "I don't need to go faster so 12 teeth is fine with me."

What's the point of 12 teeth when you could opt for 11 instead?

If you want to maximize your max. speed, go for an 11 tooth cog. If you want to maximize your average speed, unless you're a pro you probably are better off without it. Even cruising at 40km/h does not require and 11 tooth cog.

For example, take a look at this table, showing cruising1 speeds for a 11- 21 tooth cassette:

And compare to this table for a 12 - 25 tooth cassette:

You can see that the 11 tooth cog is only really useful for cruising speeds that riders at the professional level can maintain, or for short bursts. So, like I said, if you aren't trying to break your own max speed record, you may be better off with a 12 tooth cog.

(Tables screen captured from bikecalc.com. Check it out.)

I remember reading a while back about how most riders can't maintain a high enough wattage output to make an 11 tooth cog worthwhile, but I couldn't turn it up. Maybe another contributor will post it.

1 Cruising here means pedalling at 90 r.p.m.


Advice needed: cleaning / restoring parts on a vintage Peugeot I've got a vintage Peugeot racer bicycle that's needs some restoration. It's in pretty decent condition given its age (1970-1980s), but a everything could probably do with a good clean and degrease and oil to get it looking really good again.

The frame isn't too dented or pitted which is good, it's the commonly worn parts that need some attention. Parts such as the crank, derailleur, rims, spokes etc that have the odd scuff, bit of rust or bits of metal that are looking pretty mucky and has lost their lovely metallic or mirror finish.  the stain less steel or to get the chrome looking shiny and mirrored again?

What would people recommend to start cleaning these things with? Any thing that's good for getting rid of all that muck and grime?

For just wiping down the frame, dilute dishwashing detergent in water is fine.

For tougher caked on grease, I find that any citrus based cleaner that you find in your local bike shop or auto parts store tends to work well. The only caution is that it shouldn't attack rubber tires - but anything in a bike shop or auto parts store usually won't.

The usual cautions about not spraying the cleaning fluid directly into axles or bottom brackets apply. Best to spray it onto a rag first and then wipe.

If it's too powerful, it might take off some decals so you can also dilute the cleaner.

For polishing chrome and steel, I like Barkeeper's Friend after degreasing. It's not too abrasive and does the shiny.


Replaced chain, now the chain falls onto the small chaining I rode for a little while longer then I should have with my old chain, so I replaced the old chain and cassette.  But now when I ride in the big ring, the drivetrain makes a horrible sound and the chain falls from the big ring to the small ring.  The teeth on the chainring are looking a bit shark-tooth like.

I don't know if this is related but I am using this new ceramic chain-lube.

I don't know if I have to re-adjust the derailleur as it seems to shift up and down properly.

At the point where the chainring teeth look anything like a sharktooth, they won't really work with a new chain without skipping and other issues. Even if it wasn't as extreme as that, it would still be accelerating wear on the new drivetrain parts. Replace the ring.


Run 26" wheels on a 29er I recently bought an 13.5 Trek Cali for my daughter (9 years old).  I got an incredible deal on it and bought it sight unseen from an out of town seller.  After getting it, I realized it had 29" wheels on it instead of the 27.5 the more current models have.  I was actually looking for a 26" at the time, but it was such a great deal, I couldn't pass it up.

I like that it is something she will be able to grow into, but the tires are absolutely huge for her.  I did some modifications (moved some spacers and flipped the stem) so it is definitely ridable.

I am curious if I could throw some older 26" wheels on the bike for the next year or two until she gets more comfortable with the bigger wheels.  It has disc brakes so that shouldn't be an issue.

I know she is going to have a much lower BB that may lead to a few pedal strikes and it is going to look a bit akward with the longer seat tubes and forks.  But since I am changing both wheels, it shouldn't affect the overall geometry too much.

So what do you think?  I know it isn't ideal, but any reason it wouldn't work?

Edit:

I have seen this question, but it addresses only changing the front wheel (which would change geometry.  And also this question about going down to 27.5, but he is looking more for performance improvements.

If you look at bike literature from the early 29er years it was the best thing to buy. There were some issues that showed up after they became common enough for recreational riders. Recommended frame sizes tended to put people on a frame that was actually to large. It seemed that they forgot about the top tube being raised 1 1/2 inches by the larger wheels. Another issue when 29 inch wheels were put on small frame sizes was toes striking the wheels while turning and pedaling. So while a small size 29er may seem odd now they were a one point common. Manufacturers seem to have learned a lesson from all this and now put 26 inch wheels on the smallest frames 27.5 on the less small frames and make larger frames in both 27.5 and 29. All this is just to explain why you have a small frame with 29 inch wheels. The good news is that with the 27.5 boom 26 inch disc wheels are available with steep discounts. I don't see any reason it wouldn't work. It might be cheaper to buy an entire used bike if  you add in tires and tubes. Use the wheels until she out grows them, put the 26's back on the used bike and sell the whole bike for likely close to what you paid for it.


Replace 140mm fork with 160mm on Remedy 7 27.5 possible? I'm Curious about whether it's possible or whether Remedy's frame is designed  for such a replacement. Some bicycles makes it possible to upgrade to longer forks. I searched in Google, some people say that it's bicycle dependent. So, who knows about it, can I do this with Remedy or it just doesn't matter?

FWIW, I have put 140mm-100mm adjustable forks on an XC bike designed for 100m forks. Going from 140mm to 160mm will change the geometry of the bike a bit, but a bike that already has a 140mm fork is pretty slack to begin with.

Depending on the exact fork and how much you set up the sag, there may be little to no measurable difference between the two forks during "normal" riding. The slacker the head angle, the less difference a change in fork length makes. If you're planning on running it at "All mountain" sag values, then

( 140 * .7 ) = 98 mm

( 160 * .7 ) = 112 mm

So the fork will only be about 1.4 cm longer during normal riding, and at a 68 degree head angle, you will barely notice the difference in height. This assumes
the two forks have roughly equal axle to crown measurements.

If you want an official answer email trek and ask if putting the new fork on will void the frame warranty.

http://www.trekbikes.com/us/en/support/contact/

If it were my bike, I'd do it without a second thought. But I love building franken bikes.


How do I stop my rear derailleur from rubbing against my chassis? I have a fairly new Shimano rear derailleur on a cheap department store MTB a friend gave me. Recently the derailleur (particularly the jockey wheels) have started to rub against the chassis in high gears. I tried reseating it on the hanger at a larger angle, but even as far as it will go, it just wants to spring back until it hits the chassis. The best I can get it has it with very little clearance.

Here are some pictures:

Zoomed in so we can see the derailleur hanger (with "Hole A") that is bolted to the frame. It doesn't move when the axle is loosened.

I don't particularly care for the paint job, but I do want it to stop hitting against the chassis and risk affecting operation. How do I fix it?

To clarify, these Shimano Tourney derailleurs have their spring-loaded pivot at a different place to where they attach to the derailleur hangar. Pivot B is not a pivot at all, and shouldn't be free to move. However, it is currently attached at the wrong angle. The angle made between the hangar and the rigid part of the derailleur should be more acute, as in this image.

Note that there is a protruding tab on the derailleur's attachment point, and on the hangar itself. These tabs should be pressed against each other, such that the arrangement prevents that part of the derailleur from rotating in an anticlockwise direction relative to the hangar. I've highlighted the tabs that need to mate together in the image below.

You may need to fine tune the chain length and derailleur adjustment further, follow the Shimano service instuctions for RD-TX55.


Where is the best place to park a folding bike? This is quite a generalised question, but I'm looking for some principals to follow when looking for parking for my folding bike, that I just bought this morning. I think the ideal situation would be if I had an office - I would just put it under my desk then - but I am a student without an office. I want the parking to be secure, because my bike is new and shiny, and having it indoors means that it won't get wet in the rain. One of the reasons why I like cycling is that I can park very close to the place I have to be, so that leads me to think that I could lock my bike up at the back of a lecture hall, where it is out of the way, or in the passage outside. I don't want to be a nusiance, because people aren't used to seeing bikes parked inside. But, on the other hand, they probably don't understand my desire to select the most secure place to put my bike.

The prinicple I'm thinking of at the moment is to take it into the same room as I am in if I am going to a meeting, or lock it in the passage where it is out the way, if the room is too full. What about longer-term parking, e.g. parking for the whole day? Could it be in a big, open, indoor public area? It there logic to parking it outside where the bike racks are? I have a locker, but I think it doesn't fit inside my locker.

I'm planning on using it to park my car further away than usual, and cycling the rest of the distance.

Edit: I wouldn't leave it without locking it.

if you can: carry it with you. When I was riding my brompton to school, I'd just fold it and take it into buildings and classrooms with me. There were some building guards that didn't like bicycles, so a small fabric bag/cover was used to disguise it.  The brompton is unique in being small enough to tuck in just about anywhere, even under a conference table. Since it was by my knees, I didn't bother locking it up.

I have a Dahon at my parents' house which is bigger, heavier, and not easily carry-able. I locked that bike up at bike racks with a solid lock. It's hard because many folding bikes lack good places to lock because they aren't  double diamond design.


Can I use a hardtail for MTB trail riding? So, I have a tight budget of 600 USD. Now, I just wanted to say that I live in a big city, but I do want to ride trails more often. My intended use with the bike is to ride trails, and perform techniques like bunny hopping, manual, etc in order to ride streets. But after researching, I found that trail bikes are usually full suspensions - much more expensive than my budget. Can I ride trails with hardtails (120mm forks) and whether I should build my own bike or buy new.

First and foremost... Yes, you can definitely ride trails on a hardtail and it will help you get lots of technical skills that a full suspension bike wouldn't give you, unless you jumped class (enduro) on a trail bike. Plus, it will be way more comfortable riding in the city. Secondly, given your budget, i would suggest you didn't make a custom one. Buy a new one. There are lots of good ones on that budget.


Building a new Drivetrain I’m looking to build up a new dive train for a slalom / 4x bike.
Is it possible to mix and match any sort of chainring and cassette without running into any problems ?

Depending on how broad the perspective you're asking from is, the answer could reasonably be no or yes.
Going by mainstream norms, you're talking about a 1x drivetrain with a narrow-wide ring, and your main setup choice is changuide or not. Extent NW rings are basically compatible with whatever chain you want except Shimano 12, and I don't think there's a scenario where the guide you choose if any informs what ring/chain you can use. So from that perspective, among crank/ring/bb setups that give the right chainline for your rear end, the main other problem you can get into is putting a Shimano 12 chain on a ring that's too wide for it. Other than that it's basically all cross compatible, including Eagle with any narrow-wide as far as I know. (There may be some kind of fringe exception, but it's not common.)
From the perspective of all chainring setups and cassettes ever, yes, there are potential mismatches too numerous to list.
So it depends what you mean, or perhaps more usefully, it depends on whether this is an all new build from a new frame or whether there's older stuff in the mix.


Steel vs. Aluminum Wheels I was at my local bike dump looking for a spare set of wheels for an older bike I have.  He said that they have lots of steel wheels but very few aluminum.  Whats the deal on this?

What are the differences between steel and aluminum wheels?  Why are aluminum wheels more desirable?

Steel makes for a heavier rim; the modern-box section design works well for taking advantage of aluminum's lower density.  Furthermore, since steel will rust, the rims are typically chrome-plated.  The chrome plating makes rim brakes almost useless in the wet, which is exacerbated by the poor pads used on most of the classic bikes that shipped with steel wheels. In contrast, steel rims are almost indestructible - they can be bent out of shape and re-bent repeatedly and will wear much longer than aluminum rims.

As far as your specific case, many older bike-boom era bicycles were built with "Schwinn"-sized wheels, ISO 590 or ISO 597, both labeled as 26 x 1 3/8".  As far as I know no manufacturer makes aluminum rims in that size, so finding a replacement wheel for an older bike usually means either getting new brakes and converting it to a modern size (ISO 559 or ISO 584) or finding an old wheel that's not too beat up.  The latter is usually pretty easy, cheap bikes ship with steel wheels that are often simply discarded.


Tire Repair / Maintenance This question, What's the cause of the tyre cut, got me wondering if there is anything that can, or should, be done to repair small cuts in the tread of a tire. As I was looking at the damage to the tire it seemed like a bit of Shoe Goo or a similar substance might help to keep the tire from picking up other foreign material that might either work its way into causing a puncture or further damage the tire in some way.

Or is there nothing worth doing for a small cut like that?

We've tried at the local bike coop, and nothing really works.  A shim or boot on the inside helps but putting anything on the outside won't last.

Even using rubber cement and a puncture plug (like a car tyre) doesn't stick very well because bike tyres are not very thick, so there is insufficient "meat" for the plug to bond to.  If you make the plug longer, it becomes a spike aimed at your tube and pressing in every rotation.

Prevention is the only option, and that's not always a viable answer.

Narrower tyres could help too, you're sweeping a thinner ribbon of roadway with your rubber.

Someone else might like to comment on tyre sweeper wires, but I've never used them and to my mind the damage is already done once your wheel has ridden over the sharp thing once.

Later: I have successfully extended the life of a holed-tyre by adding a boot on the inside of the tyre using one of those horrendously thick patches that we all seem to have but dislike using on tubes.

The trick was to invert the tyre, and buff the inside very well with an abrasive like a file intended for buffing the tube.  Otherwise I treated it like a normal puncture repair.

The only ordering change was to return the tyre to its conventional outside-outness after applying vulcanising fluid and while it set-up, and before applying the patch.  I also used the biggest thickest patch I had.

I do not recall if I attempted to add a second patch diametrically opposite the wheel to offset the weight, might be a wise plan.

If your hole is under 2mm in diameter, give it a go.  Your only loss is a patch and some fluid, and your time.   If the hole is bigger than 2mm then sorry, its new-tyre time.


Convert urban/hybrid with hydraulic disk brakes from flat handlebars to drops I have a urban style bike that I want to convert from flat bars to drops.

Can anyone suggest brake levers that:

will be compatible with the BR-M355 calipers that came with the bike
will be compatible with the hoses fitted to the bike
are of standard brake hood construction and can be used as a comfortable hand position on drops (i.e. I'm not looking to somehow bodge installation of MTB levers)
are easily available in the UK
are not crazy expensive (< £200)
don't involve/require a cable to hydraulic conversion mechanism

Ideally, I'd prefer the levers don't include an  derailleur gear shift mechanism, because the bike has an Alfine hub, for which I'll make separate provision for shifting. However, provided any derailleur shift system can be left disconnected without impacting comfort and braking performance, I could live with it.

If I absolutely have to, I could replace the levers, hoses, calipers and disks, but I'd rather not spend the money replacing the whole brake system if I can get away with only replacing the levers.

I understand the geometry of drops on this bike might not be ideal, and some may feel I would be better off simply replacing this bike with a road bike. That's not an option for me, and neither is owning a second bike.

Thanks!

What you want to look for are hydraulic brakes for single-speed bikes. You can definitely get full sets including levers and calipers, I doubt you'll have luck finding levers that are compatible with the MTB calipers you have, check the manufacturers specs or get in contact with them directly to determine compatibility.

Not a recommendation, just an example, a little searching led me to TRP Hylex


Araya 27 1 1/4 rim and tire, max pressure I've just bought new tire (deli tires 145) for my old vintage ARAYA rim (27 1 1/4). Tire is the same size but I don't know which max pressure I can put in them, tire says min 73 PSI.

Don't worry about damage to the rim from air pressure in the tire if you inflate the tire to the recommended inflation range.

To say it a different way:

If you inflate your tire somewhere between 73 and 90 psi as labeled on the tire your rim will be fine. The pressure won't damage your rim. The steel or aluminum the rim is made of is much stronger than the material the tire is made of - assuming the rim is not damaged (extensive corrosion etc.)


Slamming my stem considerations I want to try a slammed stem but don't want to cut the steerer tube. Do I have to?

No, just move any spacers from below the stem to on top of it.
Don't cut the steerer in case you want to sell the bike later, or even if you change your mind later.


What is the impact of a buckled wheel? My rear (disc) wheel currently has a lot of movement in it. I have been riding it like this for 18 months due to intending to replace the rim (has been dented) rather than simply getting it trued. The movement has worsened but nothing else really noticeable has changed.

So I am now considering what are the impacts of ignoring a buckled wheel and continuing to ride. These must sit on a spectrum from ride comfort through to catastrophic failure but I don't understand what they are. There also in my mind be an impact on ride speed or additional energy expended by I can't quantify these.

So simply:

What is the impact of a buckled wheel?

Depends on how extreme the wobble is.  It takes very little lack of trueness to cause rim brakes to drag, but in a pinch you can usually disconnect the cable or some such and still manage (assuming the brakes on the other wheel are OK).

After that, the wobble of wheel is distracting and will make the bike unpleasant and tiring to ride at high speed.  Also, of course, it impacts the stability of the bike, making falls more likely.

If the wobble gets worse, the wheel can begin to rub against the fork or stays, and it gets unrideable.

One does need to be wary if, say, a single spoke is broken, causing wobble.  This situation puts additional stress on other spokes, making a second failure more likely, and a second failed spoke in the wrong place could cause the wheel to become suddenly quite "loopy", resulting in a crash.


What is the braking (stopping) distance for bicycles? A vehicle driver must keep enough braking distance (aka stopping distance) between him/her and a vehicle in front in order to avoid collision. It depends on the driving speed.

What is the braking distance for bicycles:

between two bicycles?
and between a bicycle and a vehicle in front?

Is it calculated with the same formula or with a special one?

And which countries enforce this rule on cyclists?

The stopping distance is a factor of:

Reaction Time
Speed and Mass (bike, rider, and load)
Efficiency of Brakes
Braking force applied (on which brakes and how applied)
Road/track surface (including water, ice, gravel, manhole covers etc aspects)
Tyre width, grip, tread etc

You have to notice a need to brake, move your hands to apply braking force. Then physics comes in, a bike of a given mass moving at a given speed has a certain amount of inertia that needs to be overcome and how much you squeeze the brakes.

So it's going to vary massively by bike/rider/situation.

The same is true of cars. Top Gear (UK) demonstrated a few seasons back the UK Highway Code approved braking distance at 60mph for a car, then showed how a reasonable car could go from 100mph to a full stop far, far, far short of that distance.

It's trained as a rule to car drivers because of the significant damage that can be caused with a big heavy lump of metal moving fast, based on very old figures.

I doubt any country enforces it on cyclists. And road cyclists in cycling groups routinely ride on each other's wheels to get the benefit of drag etc. There training and skill will come in.

Generally, the practical rule trained out in the UK for motorists (and I've been (un)fortunate enough to be required to attend a driver skills course following an incident plus opted to attend some advanced motorcycle training) is the 2 second rule.

Keep a gap of 2 seconds between you and the vehicle in front. That allows you to stop in a controlled fashion. if someone is sat close behind you, expand your stopping zone to buffer their lack of stopping zone. Increase to 4s in the wet and 20s in icy conditions.

On top of that, when it comes to bends, always make sure that you can stop in the space that is visible, so you naturally have to slow down as the road bends.

That said, keeping a 2s gap in a cycle commute is going to have the car behind you putting you at risk!


Can I straighten bent rims between two flat surfaces? I have some bent bicycle rims and would like to straighten them. I drew a basic scheme of what I want to do, the idea is to make a concrete plane mold as seen in the design to exert pressure on the bent rims. The details are on the figure. Would you have some design and/or material suggestion? It's OK if you think it's useless I will appreciate the advice.
Thanks in advance!

This is not going to work.

You won't permanently change the shape of the rim by just smooshing it between two concrete discs, as in order to permanently bend metal you need to exceed the yield stress of the metal and plastically deform it. This means that to bend something to a shape, it has to be precisely bent further than its ultimate designed bend, then elastically bend back to the destined spot. Your concrete discs will not achieve this.

It is tricky enough to form a suitably round rim from a perfectly straight piece of freshly extruded, homogeneous aluminum. Once the rim has been bent, it will have been cold worked, and the mechanical properties will not be uniform along the entire rims length. Thus, trying to precisely bend it back into shape will be impossible as the yield strength and elastic behaviors will not be fully known throughout the entirety of the rim.

Trying to heat treat it won't save you either as that will cause the rim to get softer as it will undo the designed-in cold working of when the rim is created at the factory.

Additionally, this scheme, even if it was possible, would only adjust side-to-side trueness, and would do nothing to adjust vertical trueness. You'd also have to remove the hub and spokes, and at that point you might as well just get a fresh rim. In fact if your rim got bent while it was a wheel, many of your spokes are going to be wrecked anyway.

If a rim is significantly bent, it's only future destination is recycling.


replace shimano st-ef-41-l with shimano alivio left shift My shifter st-ef41 is broken the only available shifter is the Shimano alivio or the Shimano acera. please advise Asap
thanks

Any Shimano front shifter of the same shift family (mtb triple) should work.
At work, I have used old, parts-bin shifters as replacements on repairs due to the 2020 shortage without issue, including front shifters for old mountain or hybrid bikes, and 8-speed shifters on 7-speed drivetrains.
si.shimano.com has the compatibility charts for Shimano components. the relevant part for MTB front shifter compatibility is here: https://productinfo.shimano.com/#/com/?cid=C-432&acid=C-445
if you want to confirm that the cable pull of the Acera or Alivio 3x shifter matches that of your ST-EF41, you can see that in the section "Front Drivetrain Compatibility [mtb]" ST-EF41-L appears in the box for 3x7 front shifters (SL/ST). we also see, for example, that the ST-EF505-L appears in the same box. from this we deduce that the cable pull is the same between the EF-41-L and EF-505-L.
ST-EF505-L also appears in the section for 3x9 front shifters, where it shares a box with Alivio and Acera 3x shifters such as SL-M4000-L, indicating that the 3x front shifter cable pull is shared among these systems, at least up to the level of Alivio.
You'll have to figure out what to do for a brake lever, assuming you get the standalone shifter and not an integrated unit. ST-T4000-L and ST-T3000-L are the integrated controls with mechanical brake levers and the Alivio or Acera name, although they're not the only options. often with older bikes we have simply cut the shifter portion out of the old integrated control to make room for the new shifter, rather than installing a new brake lever.
Either an Acera or Alivio 3 speed front shifter will work, in terms of having the correct cable pull. Alivio is the slightly higher-end group. if you want help choosing between the two, you can look up the shifters by part number in the specification handbook, provided you know which models you want to compare. if the Alivio option is M-4000, you'll need to go back a year or two.


Replacing Hybrid tyre I have a bike with mtb tyres size 26*1.95. I am planning to put a smaller hybrid tyre. Is that possible. If so kindly let me know what size would fit. The rim size is 26*1.75.

You can generally go down in tyre width without a problem because frame clearance is not affected.

Going up to larger sizes needs more careful checking, but down is mostly fine.

Do note your rim does not have a "1.75" measurement anywhere.  Its more likely to be 20-25 millimetres in width across where the tyre seats to the rim

One possible risk is decreasing tyre width can expose your rim to damage from potholes and kerbs, but this would be at about half the tyre size, and you're not near that.


Help please - I am suspicious this bike might be stolen I recently got this Btwin Triban 3 bike from a person I definately trust. He said they have had it for a couple of years but don't use it anymore and originally got it from a family member a while ago. Also it needs work (flat tyres, rusty chain e.t.c so it's not really rideable). However I noticed that the sticker on the bottom that all btwins have has been scratched by probably a coin, where the number/code is found which to me seems suspicious.
Also, I checked the serial number which is stamped into the frame on www.checkthatbike.co.uk and the results "couldn't find any identification the bike is stolen". On that basis, If I decide to sell it would that be ok and would I have to take anything else into consideration?
Many thanks in advance

No one can ever be certain a bike has not been stolen, unless they bought it from the shop. Not all stolen bikes are reported, and not all owners of reported stolen bikes know the serial number (many would struggle to remember the colour, let along make and model). I cannot comment on how diligent the authorities are in you location at loading the serial numbers into the database if they are provided, but in most jurisdictions, bicycle theft is not placed particularly high on the 'worst crimes' lists.

A hit in the database means its is almost certainly stolen, and the burden of proof would be on you to prove its not. A miss in the data is exactly that - a miss in the database. It means nothing as to the legal status of the bike.

The database miss, intact serial numbers and the history you have been told, give you reasonable grounds to believe you have legal rights over the bike and are free to with it what you like. Should it turn out to be stolen, you would forfeit the bike, but it would be unlikely further action would be taken against you (depending how cooperative you were feeling). (Where I live the Police seem to drive around to the thiefs house, pick up the bike and call it a good days work.  I suppose if they keep tabs on the crooks rather than shutting them down, they know where they can go to collect peoples stolen bikes).

Morally you have done everything practical to ascertain its not a stolen bike, nothing more can be done.

As far as the bar code - looks to me like the damage is simply the cables rubbing - maybe in a carrier or work stand, or maybe when the bike was being washed. Personally I take those things off, even though you don't see them, they look cheap and ugly. The state of the label is absolutely nothing to be worried about.


Adapter for a Shimano 7000 Crankset to BB30 Pressfit OK. I am confused with all these BB standards. I'd appreciate it if someone points out the correct adapter for my Opus Allegro 4.0 with a bb86.5 monocoque running on a Tiagra 4600 groupset and FSA compact crankset (pressfit) to 105 7000 crankset (53/39T).
Apparently, the bottom bracket which will come with the groupset is SM-BBR60 which is a threaded BBR60 and won't fit anyway, so I thought I keep my current BBR30 pressfit and find an adapter for the crankset and then sell the SM-BBR60. I checked Park Tool guide, but they are just too many variations and namings. Living in Canada.
Edited. Added two more photos which might help.

!

Whoever wrote their product specs was probably confused, because "BB86.5" isn't really a thing.
You have an FSA 386EVO crank. All the bikes in this series seem to have come with them.
You probably have a BB386EVO shell.
If not that, then it's probably a BB86 shell. This would require a fancy adapter bottom bracket to work with those cranks, which would be unusual for stock parts, so I doubt it's what you've got.
The internal diameter of BB386EVO is 46mm vs 41 for BB86. Pull your cranks and put a ruler or caliper up to the shell. 5mm is a pretty big difference so you should be able to figure out which you've got.
In the likely case it's a BB386EVO shell, a bunch of companies make adapter BBs for 24mm cranks for them. The thread-together type linked is nice because it adds a natural hedge against creaking, but they're pricier than some options. Cheap reducer adapter bushings exist too, which in my opinion are a compromise because they waste space that could have been used on bigger ball bearings, and add another set of surfaces that can creak. Those could adapt your existing BB to your R7000 though, in the event it still has life in it and you want a simple installation.
If it's BB86 you just need any Shimano press fit road bottom bracket.


My 1000 watt rated hub only pulls 6.7A (321.6 watts @ 48v) suggestions? I am a big boy (~230lbs) living on a mountain. My 1000 watt electric hub powered by 78 18630 Lion batteries in 13 cells barely moves me level let alone up a hill (which was its intended purpose). I tested its current to find it only pulling ~6.7 amps on a wheel stand. Times 48v only gives me just under 322 watts. Did I get ripped off? Is there something I am missing?

Under the circumstances I'm considering removing the rim and spokes, attaching a cog and connecting it (centered in the frame) into the existing chain/de-railer system, directly.

Suggestions anyone?

Even if you've only got around 300W, that should shift you reasonably well on the level. The limit here is 250W and that can manage 15mph with your weight on the bike, though the acceleration isn't great. But the current draw with no load (on a stand) will be a lot less than the loaded current anyway, so you probably can get the rated power or close to it. I assume it's actually rated to 1kW at 48V

The motor controller is important - is that suitable for over 20A? Is your wiring?


dynamo powered lighting for bike and trailer Is there wiring diagrams i can look at to get an idea on how to wire up this bottleneck dynamo to my bike and maby trailer. I've been through pages of internet blah  but found nothing yet help please?

It might help if you gave more details about your dynamo, and/or what your problem is.

There are basically three different dynamo wiring systems.

Single wire, uses the frame as a return ("earth"), relying on the bearings in your headset being conductive between frame and forks, and clamps or mounting bolts being electrically connected to the frame.
Twin wire, but one of them is electrically connected to the frame.
Twin wire, isolated.

Similarly lights designed for use with a dynamo. So the main thing is just to be sure that if the lights and dynamo have frame connections, they are consistent. If there is a pair of wires, typically one of them has a stripe on and is the earth wire.

For a trailer, the main thing is going to be reliable connectors that you can easily connect and disconnect. If it lives up to its advertising (and I don't know if it will), this system might help (and it also has some wiring diagrams that might be useful to you anyway: Dyna-Snap).
Otherwise maybe something like Anderson Powerpole, or TC-2C1PT


First roadbike upgrades I have a Scott Speedster 30 Aluminum bike 2016 with 10speed Shimano Tiagra
Flat pedals stock wheels...

I seek advice
What reasonable upgrades can I make and benefits

Thanks

The best upgrade is the one that solves a specific problem or replaces a worn out part.
Changing out any part on your bike should be done with a goal in mind. Your goals should be determined by identifying some specific way your bike could work better for you based on your riding style, terrain and personal goals. A "good" upgrade for one person could be a terrible modification for you.

Based on this premise you need to evaluate what specifically disappoints you about your bike? Here are some examples:

My riding position is not comfortable
I don't seem to have the correct gearing to meet my needs
My bike has a very rough ride.
My brakes are not performing to my expectations
There are many possibilities.

Once you identify the need, or the goal you can ask a specific question and gain specific answers. The other benefit is that you can know if the change you made met your goal.


Bosch Nyon computer -- syncs but no activities are transferred I have an electric bike with a Bosch engine (Performance Line) and a Nyon Computer.

My eBike Connect app (on iPhone) is able to connect to the Nyon (see screenshot)

but no activities are synchronised

although on the Nyon the activities are present

Is there a way to make the app see the activities on the Nyon?

When you remove the Nyon from your bike, don't turn it off, as removing it from the bike is its signal to transfer data by bluetooth to your phone. It then turns itself off automatically after 5 mins.


Asymmetric wheel. Which side should the "asymmetry" be on? I'm currently building a front wheel based on a WTB i35 rim. This is an asymmetric rim, and you can see a picture of it below.
As you see, one side is larger than the other, and I was wondering which side of the wheel that this side is supposed to be on. Should I place it so that the largest side point to the right or the left? Or does it not matter since the spoke length of both sides are identical?

Originally from  http://southernwheelworks.com/wp-content/uploads/2015/07/FullSizeRender-30.jpg

For the sake of clarity and a simplified answer:
Typically MTB front and rear have the asymmetric rims opposite from each other.

Put the 'fat' side of the rim towards the the hub flange closest to the axle center (this pushes the holes towards the center of the flanges so to speak).

On a disc front wheel, the rotor mount takes up the most space, pushes the flange in and therefor takes the 'fat' side of the rim.
Opposite for the rear, where the driver typically takes more space that the rotor mount, so the 'fat' side goes to the cassette.

Below left is what you are after for rear, opposite for front.

Seeing you asked this question, I think you will benefit from this build guide. It goes through a few concepts, and then later the specifics that would apply to get it right for an asymmetric build.

This is the reason for my answer as the wheel will be flipped and flopped as you are finding your way with the spokes and then it's easier to recall "fat side - sort flange" logic IMO.


If I puncture a CO2 cartridge, will it last a while? I bought a CO2 cartridge a while back.
I think it is used to fill up tires.

If I puncture the cartridge, will it last a while?
Would it maintain pressure for at least 6 months?

Think of these as a one shot device. Once the seal is cracked, any remaining CO₂ will leak out over time, and you have no idea just how much is left. .

How much time I have no idea, but the problem with it is as you have no idea how much is left in the cylinder (which is as likely as not no where near enough to pump up the tire), you have to carry enough cylinders in case its empty.  If your carrying enough in case its empty, you are carrying extra weight.

While I do carry one of these, on long trips (more than 30minutes ride from a road with cell phone coverage), I carry a real pump.  Between the risk of multiple punctures and loosing the gas from incorrect application (Don't laugh it happens surprisingly often)  I see these are a time saver, not a life saver.


Can a bmx hub support a 7 speed mountain bike freewheel? Been wanting to build a new set of wheels for my trail rig. Since my bike uses rim brakes, which work good enough to not upgrade to disc's, I'm going to re-use my old rims. Problem is they are 48 spoke. There isn't many options for 48 spoke hubs in the mountain bike search results, But many in the bmx search. Wondering if anyone has done this or just has the knowledge of why or why not this would or wouldn't work..thanks a lot.

You could do this by respacing a standard axle (as opposed to proprietary) 3/8" BMX hub. The freewheel thread is the same as long as the BMX hub doesn't take only metric or LHD freewheels. It's something a tinkerer might do for fun to make use of some rims. There are some issues that may hold it back from practicality:

Current standard 3/8" axle 48h BMX hubs are more or less garbage
parts. Almost by definition they only have 48h for looks at that
point, since real freestyle bikes use 14mm rear and race bikes never use
48h. There are probably pre-14mm hubs that are counterexamples, but I can't think of any that use standard axles.
The extra strength and durability of it being a 48h wheel would
be somewhat wasted given its vulnerability to bent axles, being a
freewheel hub.

Some BMX rear hubs have flange to flange distances that are significantly greater than the 57-58mm numbers usually found on 135mm MTB hubs. You'd want to avoid that, because making a derailer wheel out of one would give less lateral strength.


Racing bike feels bad to ride, can it be fixed? I bought a sponsored racer's cross country bike because of its light weight and great components (giant anthem advanced team).

I had the consumer frame of the same name from five seasons ago in a 29"er and thought nothing much would be different.

I've since crashed several times on it and generally ride poorly, and for lack of a better term the bike feels finicky and twitchy.

What is different between a racer's XC bike and a standard consumer bike that might account for the terrible ride? I'd love to fix it as a 19 pound XC bike is pretty appealing...

Pro XC racers often like a responsive bike. 'Twitchy' in the hands of a pro is fast. My guess is you are used to the 29er and the new bike is a 650B - 29ers like straight lines and turn like beached whales. If you are used to a 29er, anything remotely responsive will feel twitchy and take a bit of getting used to. I had the opposite problem moving from 26 - 29er - same end result - crashes and swearing for the first few rides.

There are things you can do nothing about -geometry, wheel size, things that cost a fortune to change - fork rake, and low cost fixes. Low cost fixes I would look to first are stem length (Increase to reduce responsiveness) and wider handle bars.

Tires and tire pressure.....

Zero cost fix is to keep with the bike till you get used to it...

Edit:
Play with shock set up and tire pressures and see if it helps. "Twitchy" could be too much rebound (not enough rebound dampening) - are you experienced enough to have a feel of how the shock/tire/track interactions are working?

Its really hard to provide an answer as there are so many things we cannot know about you, the bike set-up, the trails you ride etc.  In the end the fastest way to a solution is visit your LBS and get a bike fit, explaining your problem. A good bike shop will be able to sort you out, or at least, tell you what is  wrong.


Can I break a single speed chain with kmc universal link It maybe necessary for me to remove the chain for a deep clean. I dont think it's ever been cleared by it's previous owner.

So just to be sure I can use one of these to rejoin the chain:
http://www.wiggle.co.uk/kmc-universal-chain-joining-link/

wanted to make sure just in case I screw up a perfectly working chain.

It is a kmc chain I believe.

It depends on the width of the chain. Single speed chains come in 1/8" and 3/32" widths, so you need to know whats on the bike to use an appropriate master link.

You should also check the chain, chainring and cog for wear. If the chain is old and poorly maintained it may be time for a new one (and possibly replacement of other drivetrain parts).


Campagnolo 11 speed crank with 10 speed running gear I currently have an older 10 speed Campagnolo Record group set with 52/39 cranks.  I would like to get a compact group set. I can't get an equivalent 10 speed compact cranks now but I can get an 11 speed set.

Can I use 11 speed crankset with the remainder of my 10 speed group set?

No, Anonymous Donor is wrong, I am afraid - you will find that the chainrings on the 11s cranks are effectively closer together and you may well get issues with the chain touching the outer ring when you are on the inner ring and the smallest 2 or possibly even 3 sprockets (depends on the frame geometry). Sometimes this just causes noise and it's an irritation only, other times the lift pins on the inside of the outer ring will pick the bottom run of chain up & you will get a chain-suck type effect that can do a lot of damage.

Front mech set up is also sightly more difficult although that can be persuaded to work - it won't work as well, though, as a full 10s system and you may get chainn-drop issues going from big to small ring, and "float" issues coming back up from small to big ring.

Compact is available in 10s, in the current range with Veloce and there are still quite a few vendors advertising Centaur 10s if you want a lighter, carbon chainset.


Dahon SUV D6 frame hinge I have a problem with the main frame hinge of dahon SUV D6 folding bike.
It is hard (stiff?) and the bike does not fold as smoothly as it should. I am trying to fix it.
But i do not Know how to UNASSEMBLE the hinge joint to fix it.
Is it possible to unassemble it? Can I fix it without unassembling it?
Either way, what tools and lubricants should I use?
I send some pictures

Oil it.
Your main hinge is a permanently assembled pin.  It is not a bolt and should not be removed.
I also notice your bike has rust marks - so I guess it has a hard life and is stored outside.  This will absolutely contribute to difficulties opening and closing the main hinge as well as shortening the overall life of your bike.
Are you following the recommended maintenance?  I expect it would say something about lubricate at least yearly, and more often in harsh conditions (like outside storage)


Is there a gadget that will let me slide my seat forward more than my post allows? So I'm I'm trying to dial in the fit on my road bike to be more tri-bike like, and in doing so, I'd like to move my seat forward, well, more than I currently can.

I have the Redshift seatpost, and I really like the dual position action, but it just doesn't go far enough forward for me to hit my ideal position. Truth be told, my bike doesn't fit me as well as it should, but it's currently a better option for me to try to make it work than find a new bike.

Anyway, in my searches I came across the M2Racer Power Module which was apparently a product about a decade ago. It looks like exactly the part I'd like to have, but I can't find anybody selling one. Alternatively, is there anything else out there that would give me a similar effect?

For what it's worth, I've investigated flipping around a setback seatpost, but the Redshift goes forward further, and I've seen the Profile Design FastForward, but I don't think it will give me much more than my current setup.

No. Based on your question and your comments, there is not a product that does what you are seeking (get your hips over the bottom bracket). The reason being that no one rides that far forward.1 The old style Profile is probably your best bet for getting forward:

There are designs with a seat over the bottom bracket, even some that are made super-adjustable in that regard:

Even at that far forward, the hips are behind the bottom bracket:

With that in mind, a reason that most people don't ride that far forward is because moving yourself that far forward screws with the bicycle handling and puts you too far over the front wheel. Note that bikes that enable the most aero positions, like those pictured above, achieve the effect not by moving the saddle forward, but by moving the bottom bracket back.

Now, with all that lecturing done, I would say that if you are dedicated to this experiment, you can get close with the profile seatpost mentioned and an ISM saddle. The ISM is an anatomical design with two points and a gap between. A lot of riders slide forward on that saddle and hook their sitbones on the two points. This is opposed to traditional time trial saddles which just had more padding on the nose meaning that sliding forward just jams that thing into you perineum. Even better is if you can start with a bike with a steeper seat tube.

1That is a bit of hyperbole, perhaps someone rides that far forward.


Cyclocross racing with fixed gear road bike with cross tires I would like to take part in three local cyclocross races in the coming weeks but have a bike dilemma:

Should I convert my track frame to a new fork and put one cantilever brake on it and change the tyres, or change the tyres on my Kona road bike (I checked to be sure that there is enough clearance for cross tyres) and race with road bike style calipers but increase the calipers clearance to the rims? At the moment putting cross tyres on my road bike is the cheapest but no one uses calipers so I assume it's a stupid idea. But is converting the track bike silly too? All races are flat, btw.

Neither option is a good idea:
If you use caliper brakes for the cross race, they can easily be filled with mud and became useless.

If you go with fixie you'll be very slow on steep uphills and it will be dangerous to downhill without a freewheel.

But you can try if it will be very simple race :)


Titanium frame has a crack - advice needed I've found a Titanium bike frame on eBay. It's very cheap and the owner says that it has a very small crack on the seat tube where it connects to a bottom bracket. See in the image above:

I've never gone for titanium frames. How bad is this damage, and what is likely to happen in the future - will it get worse?

If you look at titanium frame bikes on the web you can see their warranties. Most have very long or life time warranties that cover everything but crashes and deliberate damage to the frame. So I would assume this frame was involved in a crash.

There are three types or cracks in titanium frames (from best to worst):

Weld crack
seam crack (titanium comes in sheets that are bent into tubes and seam welded.)
Stress crack

You can weld titanium (but you need an inert gas shield to prevent O2 & N2 absorption while the material cools). Seam and weld cracks are relatively easy to fix. (But still pricey.) A stress crack may not be repairable at all, and I'm not sure I would trust it in any case on the BB.

So without anymore information, I would say you have a crashed frame with frame failure. It is in the worst possible place. A repair will be expensive and may not even be possible. The repair was also not covered under the frames original warranty.

After looking at the crack again, there is another possibility. When you weld titanium you have to shield the metal with an inert gas as it cools. Otherwise it can absorb O2 or N2 from the air. If the titanium absorbs either gas it becomes brittle and will crack over time. This crack is right near the BB at the seat of two major welds. The tube would have been very hot there and if it was not properly shielded by argon during welding and cooling, it could have absorbed air during that period. That effectively wrecks the titanium. This type of problem can not be fixed. (It should have been covered under warranty though.)

Sounds like a good frame to avoid no matter how cheap the price.


Alternating two forks on a single bicycle — do I need two headsets? I have a full rigid (fat) bicycle and I am playing with an idea to use a suspension fork sometimes. I want to keep the possibility to swap the old fork back when I do not need suspension but want to drop weight instead. The swapping process does not have to be super-swift but it should be doable without special tools (i.e., only with a set of Allen keys). Almost like a wheel change, only with more steps.

Now, a fork also carries certain hardware, besides the wheel. For example, I would either need two front disk brake calipers or move a single caliper between forks. Ditto for stem and top cap, mudguard, possibly fork's remote lockout or maybe something else. All of them can be moved with hexkeys.

The headset's lower race is what I am worried about. It sits on top of a fork's crown and can be (re)mounted only using special tools, sometimes impact tools. I assume moving the race between two forks would not be easy and most likely reduce its lifespan. What are the best practices in this situation?

Possible solutions that come to my mind.

Buy a second identical headset and use only its lower race on the new fork. The headset in my case is Cane Creek 10 series. However, one top race is wasted as unused.
Transition to some sort of an integrated headset which does not have a lower race. This means removing the old one (both the top and the bottom pieces) and installing the new one. However, after that changing to another fork should be as trivial as popping the old one from the steering and pushing the new one in. However, I am not sure if there are frame/headset compatibility requirements. In my case the frame is a cromoly one.

Its a lot of faffing about to swap forks.  They're not really intended for frequent changing.

Best practice in this case would be to obey Rule 12  and to own a second bike set up the way you want it.

Your other option is to buy a light-weight suspension fork, and to make sure it has a lockout.  That gains you the ability to have a rigid, but doesn't give you the weight saving.


Can a tapered BB be installed in either direction? I have a tapered bottom bracket on my bike, like the one in the pic. On this bike, as I bought it, the fixed cup is on the drive side of the bike, while the adjustable cup is on the non-drive side. In order to accommodate the derailleur mech, the fixed cup is not done up flush with the frame, and actually sticks out a few mm. If I adjust the BB so that the fixed cup is flush, the gears can no longer be made to work, so this extra length has to be in place on the drive side, but with this being the fixed cup with no locking ring, it's hard to get it to stay properly tightened.

My question is, is there a good reason the fixed cup is on the drive side, or is there nothing stopping me from swapping the cups around, having the fixed cup flush on the non-drive side and letting the adjustable cup offer up the extra distance on the drive side?

Short answer: no.

If you're lucky the axle is simply installed the wrong way round so rather than swapping the cups, swap the axle round and see if that fixes the problem.

The two cups have opposite threads, one left hand thread and one right hand thread. If you swap them and force them in you will cross thread the frame, and that's ugly to fix.

Unfortunately that also means you can't just get another lock ring and put it on the drive side as a spacer. But if you're lucky you'll be able to find another spacer from a modern BB with plastic spacers that fits. Or you could use a thread locking compound to reduce the amount of movement.

What you really should do is get a BB with a longer axle, or a derailleur that fits the bike. But those BB's are old or cheap, and if you're buying a new one you should get a sealed/cartridge type bottom bracket (of the correct axle length for your bike). That will fix the problem and give you a BB that doesn't need servicing.


Rear Tire 'Wobble' After Tire Change I have an old huffy 26 inch mountain bike.  I changed the tire a couple days ago and now it has a pronounced wobble (side to side movement, not at the axle).  Its like its misaligned somewhere but everything seems tight to me. At certain points the rim is dragging on the brakes.  Any ideas?

Most likely situation is the wheel isn't full seated in the frame. With the bike standing upright on the ground loosen the wheel bolts and lean a bit on the bike which will force the wheel all the way into the dropouts. While still leaning on the bike tighten the wheel bolts. Be sure to alternate bolts when tightening. A lot of times people tighten one side first and the torque causes the other side of the axle to slide slightly out of the dropout resulting in a wobble.


Rear-steer tandem with middle child saddle I saw a bike for hire in France, and I'd like to track down more details on it or something similar.  Unfortunately the hire logos covered the manufacturer logos and the bike was locked up to others (all with the same colour frames) meaning I couldn't get a picture to show anything clearly.  And the shop was closed.

It was a rear-steer tandem, with quite small wheels (maybe 24").  In front of the rear rider's saddle¹ was a low saddle with fixed handlebars and foot pegs. This was positioned rather like the top-tube child seats common in Europe, but from the design of the child's handlebars it was clearly integrated into the frame at manufacture.  It looked suitable for a tall adult at the back and up to a short adult at the front. All three sets of handlebars where slightly swept-back flat bars.

This seems more sociable than putting a rear toddler seat on a tandem (where they can't be heard).  It would also have a higher weight limit and allowing panniers.

The only current manufacturer of rear-steer tandems I can find is Nijland, and they are all step-through (so no top-tube to put the child seat on).

¹ I guess I should call it the captain's as this is where the steering handlebars are.

While I never identified the exact bike, some similar bikes (rear-steer tandems and triplets in a variety of adult/child configurations) are made by a company called Amsterdamair.  They're based in France, only a couple of hundred km from where I saw the bike.  I suspect it was one of theirs though not quite a standard model.


Schwinn Circuit Identification I have a Schwinn Circuit that I got years ago from my father. I'm almost positive it is a 1987 or 1988 model based on when I remember him buying it.

It is red, with white leather seat and handle bars. It has a Sante gearing I believe and Cinelli handlebar. The frame is Columbus.

I don't have pictures right now, but hopefully this is sufficient to identify it. If so, what year is it? If not, what more information would be needed.

Does it look like this?

That's a top of the line model for the time, weighing in at 9 kilos, for a steel bike.

Here's the year's specs for 1988

And here's a story with more info


Pros and Cons of 29 "wheels I have an 29" LaPierre Hardtail. What is the difference between 29" wheels and smaller ones?

I'd like to know this not only for single trails but also on the road and / or downhill trails.

Pretty much been done to death with evangelistic enthusiasm on many forums.

Smaller wheels - more agile and responsive, lighter/stronger, easier to control

Larger Wheels - roll better over small obstacles therefore considered faster in straight lines, lower tire pressures (due bigger tire) provide more traction off paved roads. Slower to accelerate (debatable how much the difference really is) due more rolling weight.

Don't for 650's - between 26" and 29"

I grew up on 26", and switched to 29er a few years ago, my wife recently got a 650B. On the road the 29er is better, on tight, technical (i.e. have to slow down significantly into corners then accelerate) the 26" has it all over the 29'er in every way. My current preference is my wife's 650B as it suits my current riding best, but bike geometry probably plays as big a part.

You height will play a part - I would not recommend a 29er for someone under about 165cm.


Online bought bike left brake lever doesnt do anything I just bought a giordano libero 2.0, and the left brake lever has no resistance when pulled, and the front brakes don't squeeze when I push them.

The right brake lever is fine and the back brakes work well, but I don't know what to do about the left brake.

What should I do so that it works?

When you pull your brake lever, it in turn pulls a cable that ultimately squeezes your brake pads - forcing them to make contact with your rim (see image below). You should first ensure the cable exists and is properly attached. Sometimes, the attachment bolt comes loose and the cable slides freely (your symptoms indicate such)

When you release your brake lever, springs on the brake itself pulls back on the cable, causing your lever to return to its position.

If you disconnect the cable shown in the image and squeeze your brake by hand (at the pads), it should return to its open position when released. If you pull on the cable with one hand and squeeze the brake lever with the other, you should feel the cable being pulled out of your hand holding it. Pulling on the cable should return the brake lever to its original (non squeezed) position.

You can disconnect the working break to verify what 'good' feels like. Armed with this knowledge and a little bit of curiosity, you should be able to get to the root of your problem.


What make is my bike? I would like to cycle to my school but there are some questions that I can't answer like "Make of bicycle" , "Type of bike" and "Frame of bike" I would like it if someone could tell me.

The make is Apollo and the model seems to be called Sand Storm.

It’s a (full suspension) mountain bike style bike, although it isn’t really strong enough to ride off-road much. Probably great fun for riding to and from school though.

I’m not sure what you would put for “Frame of bike” as it seems synonymous with “Type of bike” unless you need to know the frame number, which is likely to be found under the bottom bracket, the part of frame between the pedals.


8-speed MICROSHIFT shifters and ultegra RD-R8000-SS derailleur I have Decathlon B'Twin Triban 500 with 8-speed MICROSHIFT shifters in the back. I am in the process of turning this commuting bike into my gravel bike. I already added new wheels and 35mm tires, Shimano chain and cassette.
Now, I have an extra Ultegra RD-R8000-SS 11 speed derailleur that I was thinking to use instead of the MICROSHIFT one. MICROSHIFT is ok but not that crisp. The question is, would it Ultegra derailleur work in this setting and what needs to be adjusted (e.g., limit screws)?

No, Microshift is usually compatible with Shimano (As far as I know, all except Advent 9 speed), but Shimano 8 speed is not compatible with Shimano 11 speed as the derailleurs have different pull ratios.


Chain loses tension on straight drop out I have single speed bicycle with a straight dropout.

The problem I'm having is that over the course of a week, the chain loses tension until eventually, if I do not re-position the back wheel again, leads to the chain coming loose.

This is a minor annoyance while the bike is configured on its freewheel, however, it could be positively dangerous if I used the fixed gear.

What am I doing incorrectly?

Are there any spacers I can fit in to the drop-out to alleviate this problem?

Or perhaps it's the fact I'm using a multi-tool to tighten the bolts. Maybe I need a tool that gives me more torque?

Your advice is much appreciated.

You need to get a tuggnut (also known as a chain tug). Surly has an excellent one that I use. I was getting the exact problem that you were until I got the tuggnut and since then haven't had a problem. They also sell cheaper ones at BMX shops or you can search on eBay for "Chain Tug" and find many cheaper options.

The other bonus is that it makes adjusting the tension really easy. You can dial in just the right amount of tension then take your time getting the wheel straight and the bolts tight.

I would also recommend getting a better spanner so you're not going to ruin the wheel bolts, but even with a ratchet I was still getting slipping. The tuggnut will solve this completely.


Fort bicycles company from Czech Republic: Where are the steel frames? Company renamed? There is or was a company from Czech Republic that produced steel frames and forks. The name of this company is or was Fort.

Why can’t I find anything about this company or their steel frames and forks?
Where can I buy them?
Where are the specs?
Where is the companies website?
Do they still exist or did they change their name?

I tried to contact (via email) the assumed company website that can be found via search engines, but I got an error mail from Mail Delivery System which states that

edward@fortbicycles.com (ultimately generated from info@fortbicycles.com)
"No Such User Here"

So I still hope somebody here may know which one is the real company that formerly built steel forks and frames. And how I could contact with them.

fortbicycles.com is only a vendor in nothern America and not the manufacturer’s website.

I would like to answer my own question, as I have investigated and found some interesting facts. The vendor name for the Fort steel frames since the year 2008 is Intec. Search for Intec, and you will find all the old frames. In this forum thread user verreweg explains the differences since the renaming (the manufacturer’s name is still Fort): The new frames are cavity sealed, have a chemical pre-treatment with phosphates (phosphated) and new stickers with the Intec label.


Do Shimano disc brakes need post mount spacers? I am switching my rear Avid Elixir brake for a Shimano XT one, but I am a bit unsure about mounting the caliper. The Avid brakes had spacers that put the brakes in the right position for the 160 mm rotor I am using, but the Shimano ones do not come with any spacers. The Shimano manual says to mount the caliper directly to the post mounts, without any further explanation for different rotor sizes. So is mounting the caliper directly to the post mounts correct for a 160 mm rotor, or do I need any spacers as with the Avid brake?

If your fork is a post mount, and your rotor is 160mm, you will not need additional adapters or spacers to fit a Shimano brake.  The image from the manual you posted is correct.


Bent spoke design wheels — feasible? The restaurant I ate at had these wheels with decorative bent spokes.

Understanding that this wheel is decorative and wouldn’t work, could any wheel with bent spokes work?

For this question, I’d like to exclude spokes that are twisted or intertwined to each other - the bend has to be unsupported as the spokes of the wheel in the photo.

Spokes bent like that can't take any load (tension), so it would not work. However, bending multiple spokes around each other can produce a feasible wheel with non-straight spokes, like the last photo here. Note that in this particular wheel a single broken spoke will cause multiple others to lose tension, most probably rendering the wheel unrideable.


How to get slower gearing on a 1x10 drivetrain Looking at purchasing a new bike with a 1x10 gearing setup.  I am concerned that with my current or future level of fitness, I may need slower gearing on the bike.

What is the easiest (and cheapest) way to get easier gearing on the bike?  Options:

Change the crankset
Change the chainring
Change the casset

This is the bike in question:

I recently looked at my 3x10 setup, with the view of going 1x. I decided to stay 3x10 as the 1x10 is a can of worms. The only other practical option was to convert the whole lot to 1x11. With 32->11-36, on the flat 32-11 I spin out a little, but am not strong enough to push 32-36 up the local hills.

What to do will significantly be dictated by the specs and components already installed on the bike in question (In this case Shimano), but ultimately, 1x10 is never going to make a great bike for less strong riders. The 10x (from Shimano, and I also think SRAM, some correct me if i am wrong) is not made for larger than 36 tooth rear cluster. The 11-36 range is not enough for many riders in hilly terrain.

Lower gearing comes from a bigger rear cog, smaller chain ring or smaller wheels. In this case, you are looking at 27.5", smaller wheels are not going to make any real difference.

You can extend max cog size of the standard Shimano 10x derailleurs (Not sure about the M610 - I think it has to be the XT derailleur)  - e.g. 'goat link' and 'radcage', and buy cassettes (sunrace) or expansion cogs to take you 10X to 42 or 46 teeth. Ultimately is not what I would choose to do on a new bike as they are all various degrees of a hack with various degrees of success.

This leaves a chainring. This bike comes with 30 - you may be able to go down to 26 with direct mount cranks, but I looks like this comes with 104bcd meaning 30 is as small as you can go without a new crank set. You don't want to small unless you don't mind going slow, or know how to spin... 28/11 is a fairly low top gear.

Ultimately I suggest if you have any doubts that go to a 2x10 or a 1x11 (Shimano has recently announced a SLX 1x11).


Properly sizing a frameset online (Ritchey Road Logic)? Longtime lurker, first-time poster. My frame is cracked and I have mostly decent parts so I am thinking about just buying a frameset and paying the LBS to move stuff over. A friend suggested I look into steel frames since I want a metal frame and don't race a ton, climb hills and long distance. After Googling I am now enamored with the Ritchey Road Logic frame. But the closest dealer is 200+ miles away. So now my challenge is to buy this frame online in the right size.
Height: 6-6'1"
Inseam: ~31.5", 800 mm
Current bike stack/reach: roughly 570 mm, 400 mm; not provided by the manufacturer).
According to the Ritchey guide that would put me at roughly a 55 cm frame (stack/reach 567/395). The next size down (53 cm) is 549/391, and the size up (57 cm) is 587/401. Current non-Ritchey bike is a 53 cm.
The head tube and seat tube angles mostly match up with my current bike, less than ~1 degree difference. The standover height (797) is 20 mm higher on the Ritchey but that's probably because my bike has a sloped top tube. But the 53 cm is closer to my current bike.
So two questions:

What else can I compare between the measurements to make sure 55 cm is more or less in the ballpark of what I need? Should I aim for smaller?
What's easier frame-wise to make adjustments with as far as stem length/angle/saddle position? Sizing up or down?

Many thanks.

I happen to be the exact same size, so I'll answer. I have a custom built road bike with 55cm c-t height and 57cm top tube. I'm using a 120mm horizontal stem and classic drop bars that have more reach than so-called ergo shape at the drops. If I for some reason wanted to have a stem with rise and ergo bars, I'd need even longer and lower frame. The 55cm Ritchey is a bit shorter and has a bit taller head tube but isn't that far off.
So, if you absolutely have to buy Ritchey, 55cm is probably the correct one unless know that your current frame fits perfectly and you want to change as little as possible.


Bike saddle position for mountain biking/jumping? A few times a week I go cycling with friends, we usually go to off-road places with jumps. I was wondering if having the saddle further backwards or forwards would affect performance?

The fore and aft position of the saddle is a highly personal position. You're going to have to experiment with it to find where the saddle should be for your style of riding, terrain, your proportions and your bike. Peter White has an article on bike fitting, which may be of interest to you. The most relevant passage is:

  take the case of two riders; Rider A, and Rider B. Rider A has very
  little upper body muscle but very strong legs. Rider B is identical to
  Rider A but has been working out at Ralph's Gym and looks like a body
  builder. The fore aft position of the saddle will be slightly
  different for the two riders. The extra upper body mass of Rider B
  will require a slightly further back saddle position to give the same
  balance. But that doesn't necessarily mean that Rider B should have
  his saddle further back. He may prefer the more forward position. Only
  he knows what his preference is.

Note that for mountain biking, you also have the option of moving the saddle up and down if you install a dropper post, which can also be useful depending on your riding style, terrain, your proportions and your bike.


Is it possible to wear out the cassette lockring threads? I have decided to do a better job of cleaning cassettes when they are dirty. Is it possible to wear out the lockring threads on the freehub with repeated use? This would be monthly on the commuter/gravel bike (biweekly in the winter), and biweekly (after every ride or two, the cassette gets dirty) on the MTB.
What about the lockring itself? Has anyone ever stripped the threads or the splines with repeated use? What about the little serrations on the backside? Removing a stripped, properly torqued lockring does not sound like a fun repair job.

Like any bolt, it  can wear down over time, even if it's being installed and removed properly.
But, the biggest issue will be with incorrect installation or removal. Main issues that will damage the lockring are:

Not inserting the tool into the lockring correctly
Using a tool which is roundered at the teeth
The threads are fine, cross-threading when installing
Over tightening - check whether the lockring is alu, if it is, it'll be weaker than a steel one
Snapping the thin washer - this washer helps protect the teeth on the smallest ring too

From proper removal and installation, it's unlikely that you will wear the lockring quicker than you wear the cassette itself. There are plenty of people who do this monthly in the summer and every 1 or 2 weeks in the winter on their bikes with an ultrasonic cleaner.
The biggest challange is making sure you don't make a mistake and damage the ring during remomal or installation. So invest in a good lockring tool and always start it by hand to avoid cross threading.


Are bicycle serial numbers no longer stamped into the frame? I found this bike ad which detailed the serial number of the bicycle for sale. I was surprised to see its simply a sticker which is far from the indelible stamped digits and letters on frames I'd seen in days past, usually chromoly or aluminum frames however. I believe this is a carbon fiber frame so maybe those frames can't receive the same treatment without compromising their structure?  Perhaps also bike manufacturers avoid the machining costs from printing a unique serial number onto the frame itself nowadays.

Is this how serial numbers are issued for bicycles now?

Barcoded labels like the one you’ve pictured are common and usually the most visible version of the serial number, especially on a carbon frame.

However, there are usually stamped/molded serial numbers on the inside of the head tube and bottom brackets.


Is Shimano the only company with a sealed ratchet mechanism in their freehubs? Most freehub designs have exposed rachets when the freehub cassette body and hub are disassembled. So much care must be taken to keep the mechanism clean and free from dirt an dust. Shimano's freehub casseste body incorporate the ratchet internally so this isn't an issue during assembly/disassembly.

Two questions:
(1) Do any other manufacturers use internal ratchets in their freehubs?
(2) What is the largest diameter hole in such freehub cassette bodies for through axles (12mm/15mm/17m/20mm) ?

Do any other manufacturers use internal ratchets in their freehubs?
Many other companies manufacture freehubs with internal ratchets, both clones that are Shimano compatible and variations of their own. Specific branded examples include the Giant FH06 freehub or the Bontrager Select freehub, but like most hubs and freehubs these are likely OEM and sourced from Taiwanese manufacturers such as Joytech
Shimano did not invent but was/is the patent holder for that design of freehub. Trying to find the specific patent is hard as Shimano has many many patents even just relating to hubs, the closest example found was this one. The word Freehub is also a Shimano registered trademark. There is more information and references on this wikipedia entry
Although unable to find specific data to verify it, the sealed internal ratchet design freehubs are usually relatively heavy, especially compared to the exposed ratchet designs, and you tend to find higher spec/higher priced hubs use the exposed ratchet design. The sealed internal design is also usually a consumable item, you just replace the entire freehub when required rather than servicing it as you can with the exposed ratchet designs.
What is the largest diameter hole in such freehub cassette bodies for through axles
I remember, so not conclusive in any way, having to get hold of a large (19 or 20mm) Allen key to remove a freehub from a hub that used an oversized axle.


Squeaky rear wheel when rotating I had my bike on a stand yesterday and decided to check the rear wheel for any issues. I then noticed this squeaking noise coming from the rear hub. It happens regardless of whether I am pedalling or not, and the intensity varies with speed.

A video of it can be found here:

What could be the causes of this noise and is this something that needs to be looked at by a bike shop?

In my experience, that sound is caused, not by the hub, but because the tire is rubbing against the brake pads. This can happen if the tire is slightly out of alignment or isn't properly trued, or if the brakes got accidentally bumped while riding (depending on your type of brakes). Try spinning your tire and watching it move between the brake pads, and you should see some wobble to it.

If this is the case, try removing the wheel and putting it back on (spin it again before tightening it in, and adjust it accordingly). If that doesn't do enough, try adjusting the brake pads (a different procedure depending on what type of brakes you have, so I can't really elaborate). If it's still giving you trouble, then the wheel is misshapen, and needs to be re-trued, which is probably best done by a bike shop, but isn't too hard to figure out on your own.


Convert Shimano Ultegra 6870 rear mech from short cage to medium cage I would like to ride with a 11-32 cassette but I have a short caged Ultegra 6870 derailleur. Can I just swap the cage? Or are there other differences between the derailleurs?

Cheers

In short, yes.

A single web search for "Ultegra 6870 derailleur spare parts" will find an exploded view diagram with spare part codes. It is fairly clear that the only differing parts are cage plates. The parts go by codes Y5YC98080 and Y5YC25000.


Do crank arm pullers vary in sizes or there is just one size? Just want to confirm if there are different types of crank arm pullers? I'm trying to order one and the contact person is telling me that he has one but for a road bike. Now I'm confused I thought there is only 1 size of crank arm puller, so are there different sized of crank arm pullers?

The main distinction is whether the puller is for square taper (and Powerspline) versus Octalink/ISIS. Among square taper crank pullers, there are some older ones made with nutted spindles in mind that don't play nice with the now more common bolt-style ones because their tips are too narrow and can jam into the bolt hole and damage the threads. A couple companies now have good all-in-one tools with switchable tips that work on both square taper and Octalink/ISIS.

There is no road versus mountain distinction with crank pullers.

One size of extractor thread has been used on the vast majority of cranks for a long time, M22x1. There are several older sizes on cranks made by T/A, Stronglight, and possibly some more obscure ones, all of which need their own extractors. There's also some more contemporary brand/model specific designs such as the Profile ones and Cannondale SI.

Within BMX, there's now about a million model-specific crank removal tools, and a whole other discussion of cross-compatibility.


Long Distance Route for a Beginner! I've got some questions about cycling and gear that I need!
So I'm planning a route through North and Republic of Ireland in April, and the route will be about 430 miles. I don't cycle often, but I do some day rides once or twice a year. My last ride was about a year ago, and I was able to cycle for 35 miles that day, and I'm planning a similar route this weekend just to get back into cycling bit by bit.

I'm asking more about the gear I need, also because I've never cycled in cold weather before (Californian living in Scotland--help!)-I've got Viking Spirit Road bike, good Ulock, lights/reflectors, basic patch kit and pump, helmet and compass.

I know basic bike maintenance like patching a tire/tubing, removing and putting back a wheel/tire.

I'm planning to get gloves, padded shorts, a rack and side sacks.

Do you think this equipment will suffice for a 2-3 week bike trip?
Also, what else do I need to know for a trip like this?

Any information is appreciated for this.

EDIT: as preparation I'm cycling this weekend for 110 miles over 3 days. And i'll be doing trips like that for the coming weeks before the 400 mile trip.

A further suggestion: before your last training ride but after most of your training miles, get the bike looked over by an expert. This probably means booking it in to a shop for a service (clean it first) but it could mean instructions and/or an knowledgeable friend. This would also be a good time to get some tough tyres put on if they're in the budget.

Also (things that have caught me out on long day-rides etc.):

Carry tubes as well as patches  (which are a pain in the wet).
Test your pump from flat before you go.
Try out your clothing as well as your bike.
Figure out your navigation. For example I like a smartphone in a cheap top tube bag, displaying a route prepared in comfort but not turn-by-turn directions. There's free software that uses openstreetmap (also free). Others take different approaches. If your distance is a challenge to start with, getting lost really saps your willpower. But of course you may want to explore along the way.
Carry full finger gloves even if you don't think you need them; carry fingerless as well if you're prone to getting hot
Get on the bike as much as possible before then. Even if it's just going to the shop the day after a long ride.


New suspension fork - how much should I care for locking on the handlebar? I'm putting together a bike that will allow me to go to work. I work in a warehouse outside of the city I live in, and I want to avoid roads trucks take because I haven't ride a bike for about ten years. So my road will be bumpy, a bit off road.
I was planning to get a suspension fork with air shock absorber, one that can be locked from the handlebar. I'm on a budget and it was on ~30% sale, but the seller can't find it. Like, literally isn't sure if he has it in his warehouse. He has a similar one, slightly cheaper, but lock is on the fork itself.
I never had a fork that was anything more than stiff steel or aluminum, I'm ten years behind, or more, when it comes to riding technique and bicycle construction. You may well assume I know nothing. So, how much should I care about having suspension locking on my handlebar versus on the fork? Both in terms of money and time spent looking for something in my budget?
My usual route would be half by paved roads, and other half by unmaintained roads, dirt track, mud, stones and a shortcut thorough the woods. I could, in theory, ride asphalt, but I will not dare to use the same road big trucks are using. And I want to be able to take it sightseeing in Bieszczady, Polish low mountains with woodlands paths.
Please don't advise me a stiff fork here. That may be a sound advice but it would be outside of the scope under this question.

Thank you for your answers. I managed to get one with lockout on the handlebar for a price of the one with lockout on the fork - the piece seller couldn't find was put away due to imperfectly printed manufacturer name. Win-win, I got a "nice to have" feature for free, seller does not need to send it back for repainting.

Any fork lockout per-se is a sign of suspension design limitations, one would argue. An ideal suspension system would tune the closed/open states by its own, and there are attempts to achieve that (Specialized Brain, Magura Elect etc.).
Rider's mental energy spent on making lock/unlock decisions translates to lost joy of the ride. Unless every second counts, i.e. one is racing against the clock, and needs all the efficiency all the time.
An always open suspension fork will not turn a ride over a smooth surface into suffering. A little loss, not unlikely unmeasurable, of pedaling efficiency will happen, and that is it.
Similarly, a proper fork, even when locked, will have a blow out valve to open up by itself when a rider encounters a bumpy segment. However, this situation is more dangerous than leaving the fork open all the time. It is better to foresee the need to open the suspension than to rely it to happen on its own.
The difference between lockout control placements manifests itself in how much time the cyclist needs to spend to switch it. When commuting, touring or leisure riding, lost seconds to slow down, find a knob on the fork and turn it are really not that critical. When racing, slowness is of course unacceptable and a lockout placed on the handlebar is preferable. Not that it does not have its negatives: 1. One more knob on the handlebars to mess with; 2. One more cable and housing to periodically replace; 3. Additional weight of additional components.


Mounting light on handlebar with bag installed On my bike I have installed an handlebar bag (the Ortlieb Ultimate 5).
Since I am also considering installing lights on the handlebar, I am afraid they will be simply shielded by the bag.

The clerk of the bike shop where I asked for information assured me the handlebar bags are designed to ensure handlebar lights can be used, but I am not sure and I don't want to try it by buying an expensive light that I cannot then use.

In the picture you can see the bag holder as installed on the handlebar. The bag will exceed its level of few centimeters.

As Chris H notes, the clerk was wrong. And he suggests a good suggestion to raise the light above the bag. However, you can also mount the light below the bag as well. Operating on the same principle as fog lights on cars, low mounted lights can do a better job of showing some road hazards. They are also much less likely to blind drivers and pedestrians (StVZO-compliant handlebar lights are still sadly rare).

There are lights that will mount on the crown of the front wheel fork (where the bolt for caliper brakes and mudguards attaches), but those might still hit the bottom of the bag -- although the Ortlieb bag shown in Christian Lundvig's photo is quite small and thus compatible with fork crown mount lights.

Here's a google image search for "bicycle lights fork mount". In addition to the fork crown lights, there are also front fork adapters that let you mount handlebar lights on one of the legs of the front fork.

Here's a blown up image of the top left two -- a fork-mount adapter and a light mounted on said adapter. Note that this placement is just about where ye' olde friction dynamo lights used to be mounted.

Another option is of course a helmet light:


Is wear on this derailleur pic normal? I have had issues with noisey drivetrain and inconsistent shifting despite indexing adjustment.
I have found wear on the top jockey wheel cage, is this normal or should the chain not rub here?
Does this indicate a bent derailleur / hanger?

In my experience it is usually the derailleur hanger that gets bent. After all derailleur hangers are built to be the weakest point so that in case something hits the derailleur neither the frame nor the derailleur is damaged. The hanger is just a 15$ part.

There is a derailleur hanger alignment gauge, which bike shops use to check whether the hanger is bent:

http://www.parktool.com/product/derailleur-hanger-alignment-gauge-dag-2

One can even use this tool to bent the hanger back if it is only slightly offset. If you ask nicely and come with the derailleur unscrewed your lbs should check that for free, it only takes 2-3 minutes.

If the hanger is ok then the derailleur might indeed be bent. But the first thing to check is the hanger.

(All this advice under the precondition that the derailleur was correctly mounted, adjusted and only matching components have been used (no 10 speed shifter on a 9 speed drivetrain, no different generations in the parts, only compatible SRAM/Shimano mixup, etc.)


Can't find nuts for old mavic wheel I picked up an old mavic wheel, and I'm having a tough time just finding some nuts for the axles. I went through a bin at my community bike shop and couldnt find anything that fit the threads.
The wheel says CXP 22 on it.

Is there a specific kind of nut I should be looking for for these wheels?

Turns out i needed race style nuts. The kind of nuts that have a flared end thats independent of the rest of the nut.


What kind/model is this frame? Can someone help me what kind of alpinestars bike frame is this, and where it is manufactured? Just got it a year ago.. I've already search alpinestars website but couldn't find this exact frame..
Here is the bike's serial number JYW16047461

Alpinestars hasn't made bikes since around 1996. This is definitely not one of their 90's frames. That being said they do sponsor mountain bike teams and make clothing and gear. It is not unheard of for these companies to get lower end frames from the manufactures of the brands their teams ride and have them branded for them. My guess is that is what this frame is.


Are full carbon forks less prone to failing from hidden defects than those with alloy steerers? Are full carbon forks less prone to failing from hidden defects than those with alloy steerers?

Even though the mechanics couldn't find problems with Richard Stanton's bike, his fork failed catastrophically at 35 km/h uphill. He took good care of his bike. Manufacturing flaw, frame fatigue or corrosion in the steering tube were the possible causes of the fork weakness.

If his fork was full carbon, could his diligent check ups and maintenance have prevented the accident?

From my understanding, bonded alloy can hide damages and make the tap test unreliable. You can't tap the carbon part that's covered by metal unless you separate it. Here's a tap test demonstration.

Some articles about the incident:
http://www.stickybottle.com/latest-news/amateur-rider-49-dies-on-coffee-spin-after-carbon-fork-snap/
https://cyclingtips.com/2016/12/after-the-death-of-a-canberra-cyclist-should-you-be-concerned-about-catastrophic-fork-failure/
https://www.smh.com.au/business/consumer-affairs/should-there-be-a-safe-life-for-bicycle-parts-20161118-gss41s.html
https://thewest.com.au/news/wa/cyclists-falling-victim-to-an-undetected-danger-with-their-bikes-ng-b88329369z

Short answer: no.
Longer answer: not always.
Proper answer (IMO), with full disclosure and explanation (of the reasoning):

In the presence of electrolyte, aluminium will galvanically corrode with carbon. First (old) versions of alu-carbon combinated parts were more often prone to this. Good sealing and carbon-aluminium interface design can help prevent this. Nowadays there's no rule of thumb - both for alu-carbon and for full carbon forks and frames. Some are well designed and well manufactured so they last long. Some are not.

Digression:
While with steel and aluminium manufacturers have come up with methods of designing and building frames so that even if they fail, cracks first show up on the outside (small, like a thin hair-thickness line, but visible with "naked eye"), and pre-ride checkup is all that's needed, with most carbon parts this is still not the case. Which is the scary part - parts failing catastrophically without prior warning. Don't want to do any fear mongering, modern good quality parts of renowned manufacturers are a safer bet and carbon is the frame material of the future IMO, just take a bit more caution when buying and using. Explained in digression 2 part.

Digression 2:
Testing carbon parts for flaws.
Tapping test can show some flaws, but not all. Ultrasonic scans are a safer way of determining faults. As is explained in this Tapping Test Youtube video.
Long, a bit tedious to watch, but very instructive video on carbon parts care, inspection and problem causes is this one: Cutting up expensive carbon frames.

Digression 3:
Care of carbon.
Having chosen a good quality part (whether frame, fork, bars, seatpost...) from a reputable manufacturer, care still needs to be taken.
Using copper mounting paste for good grip with optimal pinch bolt tension when mounting parts (except on stems, for reasons explained nicely in this article - in the comment section I've had a very good and informative discussion with the author and learned a few things - Headset bearings don't last forever).
Beware of any paint scratches and chips - it is needed to protect moisture from entering. Moisture delaminates fibres from the inside, making carbon parts fail. It also protects the resin and epoxy glue from disintegration by sun rays (modern carbon parts have UV blocks added within the material as well, but to be on the safe side...). So paint touch ups using paint that won't harm the epoxy is a recommended. Metals will show visible rust signs on the outside, while carbon parts will start delaminating on the inside very often, without visible signs until it's very late.