Mechanics and Fixing Any Questions Answered

Might ride to Manchester one of theses days... but it’s not a particularly interesting tour choice, is it? London to Manchester? 🧐

👍🏻 😉

Tag along on the Rapha ride.

😎 sounds like fun!

having an issue with my SRAM Yaw FD. Chain is rubbing (in the big ring in the first 2-3 gears), but only at the top of the derailleur when the chain is under load. Tried to raise the FD height, but to get it high enough to clear it won't shift. suspect it's because i've tried to fit a 34T cassette but is there anything I can do before I go back to a 32T

What size is your small ring? Could be too big a difference for the FD.

50-34 chainrings, 34-11 cassette. Had no issues with a 32-11 cassette (although a LBS did set up the fd last time)

Right, my bad, thought you’d changed a chain ring.

Only thing I can think of is to check the yaw angle, but you’ve probably thought of that. Interested in the solution when you come across it. Good luck.

I don’t know what is going on but I am having an absolute ‘mare. I have a Chorus 11 speed rear mech that came attached to the hanger when I bought it. I cannot get the T25 to budge and undo from the hanger in order to fit to my frame that has an incorporated hanger as part of the frame. I have tried soaking in pb blaster, and clamping the hanger in an axle with a qr but still can’t get it to budge. The T25 grips well and isn’t spinning, but it is hard to get that much torque through it but that doesn’t feel like the issue, but it is totally solid! Is there anything I am doing wrong beyond this?

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Sounds like it’s seized, get heat on it and lots of it. Heat the hanger, not the derailleur. It will come off. You will want a vice to hold the hanger whilst it’s hot and to allow you to get the thing undone.

Cheers for the reply, I figured this might have been the case. Also wondering whether a ratchet/socket set with T25 head might provide better torque than the long-handled t25 I have access to!

Moar leverage.

If you’re happy to sacrifice the hanger you could cut it off. One or two cuts up to the thread will be enough to then break it off and not damage the derailleur

Chainline quiz:

1x10 Shimano drivetrain with narrow-wide ring up front and 10-speed cassette on Deore FH-M510 ‘9-speed’ freehub, 135mm axle, no spacers on cassette.

Current chainring is sat 43.5mm from centre of frame and I’m getting slight chain rub on small cogs.

Should the chainring be further out?

no spacers on cassette.

There’s your problem. There should be a spacer between each cog.

Jokes aside, does it rub in the largest cog/s? What BB width does your crankset recommend?

I need to replace a stolen roller brake wheel, 700c with Shimano Nexus roller brake, but I don’t know how to check if the various brakes I see online are compatible with the wheels I find. Does anyone know how to tell?

Edit, these are the wheel and brake options I’ve found, but the website doesn’t specify if they’re compatible. Sheldon brown doesn’t go into it either.

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If you've got a 10 speed cassette on a 9/10 speed freehub, you should have a 1mm spacer between the freehub and the cassette. Won't necessarily solve all issues, but won't make them any worse and will make them slightly better.

Due to the cog spacing, a 10 speed Shimano cassette is actually narrower than a 9 speed one.

Thanks!

I’m having a new set of wheels built with the correct 130mm rear hub, so will rejig everything once they’re ready and start again.

@Hjusth maybe give practicalcycles or SJS a ring, they both are quite knowledgable on roller brakes.

My understanding is that all Shimano & SRAM roller brakes are interchangeable.
The hub / roller brake interface is the same.

I recently built a Nexus 8 speed rear hub and put a Shimano (non Nexus) roller brake and it works well.

Bike is here:
https://www.lfgss.com/conversations/347657

Thanks @TheShipwright and @Vince. Went ahead and ordered the parts so will post what I learn.

Park Tool BBT-18 Bottom Bracket Tool. They say to use a 36mm socket, but it's 8 sided... I know I can just use a spanner, but any suggestions for how to use with a torque wrench?

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36mm crow foot

Perfect, thank you.

Why is my chain rubbing on the seat stay when on the 11T cog?

130mm rear frame spacing, 10-speed 11-42 Sunrace cassette, Chris King Classic rear hub 130mm QR axle.

Anything I can do to fix, or will I have to set the mech limiter to avoid smallest cog?