F&@£ing bottom brackets!!!

[FluffyChicken]

I agree, I have some Race Face cnc cranks I need a bb for. I'll be buggered if I know which length I need.

That's easy, just post up model or/and a picture.

 

[benjabbi]

I feel your pain. Going through the same thing with my Middleburn RS-3s on a Trek 990. But have discovered they need a 122, however the chainline doesn't seem right so I now need to faff with chainring spacers...

RS-1s and 2s used a BB that long, 3s were low profile and want a 107-110mm BB.

 

[FluffyChicken]

I feel your pain. Going through the same thing with my Middleburn RS-3s on a Trek 990. But have discovered they need a 122, however the chainline doesn't seem right so I now need to faff with chainring spacers...

RS3 are super low profile cranks, like M900 XTR.

They are 107mm cranks.

Are you sure they are RS3?

 

[FluffyChicken]

...

The first one is my Mongoose Amplifier. I built it with M900 cranks on a 110mm BB length, which was perfect. I then purchased a set of NOS L&M Stardrive cranks, which hit the lower pivot at the back of the BB shell, so I bought a 115mm BB, which now JUST skims the pivot, but is unrideable! I could put a 118mm BB in, but then I'm questioning the chainline!

....

I have in some notes, Stardrive at least the DH version use 118mm or may use 115mm if in double setup.

 

[BerthaPog]

The new standard being:
BB90, BB95, PF86, PF92, BB30, OSBB (road), BB30A, BB30-83 Ai, PF30, OSBB (mountain), PF30A, PF30-83 Ai, BBRight, BB386 EVO, T47, Threadfit 82.5, SRAM DUB

SImples.

From XKCD…

 

[ishaw]

I thought rs3s used 113 axles?

 

[FluffyChicken]

I thought rs3s used 113 axles?

they can do, just a different chainline

 

[PhillB]

Yes, it is a bit of trial and error if you get a frame without a BB in it to restore. I have box with 'wrong' BB's in it, so I'll just have to buy a variety of frames to use them up!

 

[MCA4President]

That's easy, just post up model or/and a picture.

Ah okay thanks, sorry for spamming the thread with my issues, but it's these cranks. I realise I have them mounted on my Zaskar, but they've since been taken off and replaced with an XC Pro crank which used a wildly different BB length. I've long since sold the BB these were mounted with so can't recall it's size. I'm think somewhere around 118/120mm?

 

[FluffyChicken]

107 for them, they're Turbine LP's
(of a super low profile design)

Your XC Pro will probably be 122.5, a normal profile design.

Unless they are XC Pro MicroDrive, which have a low profile design and are normally 115mm.

73mm shell can alter it a bit for superlowprofile if the BB cannot recess the flangy bits you see on some of the cranks.