New answers tagged

1

The gap you're talking about is more or less random and does not itself affect how symmetrical the Q-factor winds up being. The quick visual check for Q symmetry is to eyeball against the chainstays, which is close enough in almost all cases to know whether there's a problem unless the frame either has an asymmetrical rear end or is smashed. To get an exact ...


2

From the picture of the left hand side BB cup comparing it to pictures on the Praxis bottom bracket web page here I think it's certain you actually have a ISO (aka BSA or English) threaded bottom bracket shell. This can be confirmed by looking at the drive side cup which should have an indicator for the direction to tighten it. Some Praxis BBs fit in press-...


4

If it is an M30 Thru BSA, then the cups will say 'M30 THRU'. As they say M30 and only M30 then they are the M30 BSA version. The latter suits crank spindles which are 30mm drive side, 28mm non-drive side, as the Zayante crank is. If they say anything else (like press fit) then (future readers) can match that to other models on the Praxis website before ...


2

Pic 1 shows that the outside plate of the FD is unnecessarily far out. It should just be a hair away from the chain when in big front and rear small. You'll have to adjust the limit screw quarter turn by quarter turn, so that the chain climbs on the big ring and does not rub against the outer plate. Also the outer plate should be parallel to the big ring. ...


2

Like most bicycle components cartridge bottom brackets are highly standardized. Almost all bikes with threaded bottom bracket shells are ISO standard: 1.37inch x 24 threads per inch, drive side is left hand threaded. The ISO standard is also known as 'English' or 'BSA'. Obviously this is what your frame has. There are two other parameters you need to know. ...


1

BSA 68 is the bottom bracket shell type. BSA determines the threads an shell length, so this needs to match the frame, so it should be the same as old BB. 107 is axle length. This is determined by the crankset, so you need to find the specs for the crankset you want and take the number there. Track bikes have standard chainline, so unless you want to ...


5

If you just want to go with something basic that's close to what you have, it's easy to get a replacement repair type crankset for this sort of bike. Check your tooth count, but it's probably 42/32/22, and then check the length, which is usually stamped on the inside of the arms. It will probably be either 170mm or 175mm. The other distinguishing factor is ...


6

Nothing is missing. To adjust these you loosen the pinch bolts on the left crank with a 5mm wrench, use the same 5mm wrench to gently tighten down the large black preload adjusting bolt that's found on the outside of the left crank, and then re-torque the pinch bolts. This bike appears to be in pretty rusty/unkempt shape. It would be a good idea to at ...


0

Looking at the Praxis web site it looks like M30 is a proprietary BB and you need a specific Praxis M30 to BB386 adapter. Strange that you tried PF30 BB units in a BB386, but I think maybe the cups and bearings are the same. According to https://www.bikeradar.com/advice/buyers-guides/the-complete-guide-to-bottom-bracket-standards/ they both use 6806 ...


5

I think what is going on here is that you were running a 47.5mm chainline (standard for MTB triples, see here) with the FY301 crank, but the M361 crank gets you a chainline of 50mm. When switching out three-piece cranks you have to pay attention to the chainline and you also have to look at cartridge bottom bracket axle lengths and potentially replace the ...


3

No. The chainring needs to be compatible with the rest of the drivetrain. Chainring pitch (width + spacing) gets tighter with increased cogs on the rear wheel. So a 9 speed chainring is not compatible with an 11 speed drivetrain. Additionally there are new narrow-wide chainrings for single chainring setups will not work well in a system with a front ...


0

I've finally gotten to the bottom of the bottom bracket problem. The thread inside the spindle was worn and the NDS crank arm was moving independently from the DS crank arm. Have replaced the FFS with a cup and cone BB with a retro chain guard, which is now engaging nicely. Still have, what I now know is chain slip, just got to sus out whether its the ...


3

There is an item Shimano calls a crank Plate Pin, which is that black plastic plate visible on your crank, and circled in the diagram below (4). It has a little pin which should stop the crank coming off in this situation, yours must have been damaged if the crank came off and it should be replaced. Many internet commenters scorn them but has worked for me ...


5

Shimano Hollowtech II cranks use two pinch bolts to secure the crank to the axle. From your picture it looks like you have those. You are missing the plastic end cap, and you may possibly be missing a washer that sits between the crank and the frame. There is no spacer, the play is probably because the crank arm is not fully on the spindle. To install the ...


0

I believe I mistook mixing English words PLASTIC SLEEVE, DUST CAP, SPACER and SEAL into one thing so make my words hard to be understood.  I have installed the Ultegra crank but I am not sure whether it is the best way. I am now trying to explain what I was facing and my solution as best as I can. (sigh, language is a big issue) The dimension of the Wilier ...


3

It looks like your bike has a Quarq Prime alloy crank. The picture below is a shot of the crankset from behind the drive-side arm, where the spider attaches to it. This appears to be a crank that takes a separate spider, which mounts to a splined interface by the crank arm. The pic above is a shot of the reverse side of the drive-side Prime crank arm. The ...


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