Mechanics and Fixing Any Questions Answered

Isn't the axle length the same, you are just spacing the BB on a 68mm shell?

Yeah that's what I'd originally thought (hoped!) but the evidence does seem to be pointing to not being compatible. The SRAM Rival 1 product page suggests only 68mm BB compatibility but not sure if I'm reading it right. But also that page says the spindle diameter is 30mm but when I measure mine it's 24mm, so maybe I'm not looking at the right thing.

you may as well get whatever BB suits the new cranks you want rather than trying to match to gxp.

Yeah that makes total sense, thanks. I guess given the rest of what I've got is SRAM (X5 10spd derailleur and X9 shifter) I'll probably stick with SRAM cranks for the sake of harmony!

Thanks for the input all, really helpful 👍

But also that page says the spindle diameter is 30mm

There's a 24mm and 30mm version of a lot of them, and a bunch of DUB ones now I guess, and confusing instructions for a lot of them.

Maybe I'm confusing things then, mine are spring clip ones, are those reusable? I was always under the impression they weren't meant to be reused although I've been doing it for years and never had a problem...It's just that now that I've started waxing my chains, I have to break the chain much more often (every week) and I didn't trust it enough for this.

I have re-used the links that you bend a little to pop the front plate off multiple times and never broken one.

That said, if I was going to be routinely breaking a chain (for waxing say) I reckon I’d be looking to use a chain with a threaded fastener like the Izumi Super Tough.

Increase in longevity of the chain due to increased maintenance would offset some of the additional initial outlay.

What is the maximum size large ring that anyone has got away with on a Tiagra 4703 triple?
Shimano says only 30/39/50.
But based on past experience I know that I can usually get 22 or even 24T capacity, but that the middle/outer ring gap needs to be preserved. Ideally i would like 28/41/52. Anyone think it would / would not work?

It's for a tandem and I want as broad a range as possible as the guy it is for wants to do both hilly-ish club rides and the odd TT.

Has anyone had experience of sram cassettes getting a bent sprocket? 12 spd eagle cassette and on the 2nd sprocket there is a clear rubbing/grating noise at the same point of the cassette. Only happens on that one gear and it also makes the shift to first sluggish. Any suggestions what to do? Try to bend it or ask for it to be warrantied?

I got a customer killing one just like that yesterday, but it was a huge bend. If it's only a little you can tap it carefully until it's straight. Still, a new cassette will always be better.

How are you supposed to let air out of a wheel with a valve extender?

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Unscrew or a cocktail stick

Acquired a bb7700 from the bay. There is this moving part inside the spindle that rattles inside. It's pointy on one side, flat rubber on the other. What is this and how do I fix it?

edit: seller confirms its not meant to be there... just need to work out how to get it out without damaging the spindle

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@coffeekeyboard that shouldn't be there.

Cheers - managed to remove it with brute force

What are these for? They came with a disc adaptor.

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They go round the bolt heads that attach the caliper to the adapter/frame. I think they're used as indicators should the bolts start to come undone for any reason.

What are these for?

Landfill.

They're to practice throwing stuff in the bin from across the workshop.

@M_V @snottyotter @Bearlegged cheers

Not sure if the right thread but looking for recs on someone who'd be able to respace a steel frame rear triangle. Just looking for someone to help with my runaround to go from 135 to 120 to make my life easier.
My 2 nearest LBS's tend to sneer at anything less than a full bike build/strip - which I do understand to a certain extent.
Anyone have any suggestions in London? Ideally in East?

is there any way you can fit a couple of spacers on the axle? ie a 5mm spacer on each side, then you'll only have to squeeze the frame by 2.5mm per side when you tighten the axle nuts.

if the axle isn't long enough could you replace it? just think it's a bit of a jump cold setting from 135 to 120.

You could ask SBC maybe

Haven't really dealt with frame adjustments tbh, so didn't really think the jump would be too much but appreciate the advise. I'll have a look at the suggestion to possibly figure out a workaround.

I'm looking to swap c.2008 Shimano ultegra stuff between two bikes.

Bike 1 has 10sp 53 - 39 and a triple mech bodge. I commute 99.9% on 39 and it doesn't shift well (there's a knack to it) as the range is too wide at 14.

Bike 2 has 10sp 50 - 34 compact I'm currently using it on zwift with rollers and am a bit undergeared on bigger efforts.

If I chuck the 53 -39 over to bike 2, I'll just have to reset the front mech higher, is that right?

I can then run the bodge hack on just the 34 spin ftw until I can source another double mech?

Am I overlooking owt?

Hi all. I’m doing up my Bontrager Racelite frame atm. Two of the bottle-cage bosses are spinning which means I can’t screw a bolt in (see picture).

They’re sort of riveted, and can’t get purchase on the flat washer in order to sort it out. Is this a welding job, or can anyone help with a less costly fix?

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use a nutsert tool to "pull" them up

or make yourself one

https://www.youtube.com/watch?v=qhzVDvnN_yM

The quick release lever on my 105 5800 rear brake gets jammed half way open, does anyone know of any fix?
I've tried the usual soaking in WD40, forcing it and wiggling it about but it the action gets stuck at the exact same spot.

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Noob question but want to be sure before I order something… When measuring stack height for a threaded 1 inch headset, should one measure the whole length of the steerer tube (to the fork crown) or to the top part of where the crown sits (just at the start of this slightly thicker section begins)? Cheers!