Bottom Bracket Length for Mid 90's Orange Clockwork

stevenk4563":q9wzswk0 said:

Now I'm really confused this is the chainset I've got

http://www.chainreactioncycles.com/Mode ... elID=46025

Click to expand...

Using Shimano docs linked above....
113mm length is the recommended length giving 50mm chainline (modern front chainset position)

If you currently have a 107 or 110 length, give that a try first as you front mech and bike are probably using a 47.5mm chainline, what with being old

Thanks, I don't have one to try so will order a 113, if the front mech is an 'old' type, will it work with the 50mm chainline or will I have to buy a new style front mech as well?

send the new chainset back, and but a retro one

stevenk4563":24ud9yq4 said:

Thanks, I don't have one to try so will order a 113, if the front mech is an 'old' type, will it work with the 50mm chainline or will I have to buy a new style front mech as well?

Click to expand...

It will be fine.

Not all cranks are the same yeah ?

If you want a raceface turbine crank on there it will require an axle of a certain length
If you want a Shimano XTR crank on there it will require an axle of a certain length
If you want a middleburn crank on there it will require an axle of a certain length which is a different length to the turbine one and the XTR one.Or they might be the same :? Point is you decide what crank you want to put on then ask us if we know which axle suits it. Given the VAST depth of knowledge on here its highly likely someone will know the info off the bat.

Its the crank itself that determines the length of the axle. All cranks are different so you can assume that its likely all axle lengths are different, this isnt completely the truth however. Many things are very similar so you find many things are interchangeable.
You can look deeper into this concerning chainline,frame etc but for the vast majority you dont need to,its such and such a crank and therefore its such and such an axle length.

I myself had a bit of a job finding the correct length for a pair of early American AC components cranks. There was nothing i could find to easily get the makers recommended axle length and in the end it was someone posting a picture of the cranks from a company flyer that had the axle length info on it.


I hope this has actually come across clearer to you and not made things worse





I take it you intend to grease the axle taper ?

....Which in case you missed it is an unhelpful reference to a can of worms. Do not grease the taper. It does not need greasing and doing so increases the risk of damaging the crank....although unless you are ham fisted it's a small risk..... But why take the chance.