calvin17d

Just picked up a new set of Campy Centaur Crank arms already rigged up with an Origin 8 46T Chainring for my single speed. It appears I need a 111mm BB spindle...Can anyone veryify********** If so does anyone know of a manufacturer other than Campy that makes these excluding phil wood?

Shimagnolo

I just built a bike with Centaur parts a few months ago.
IIRC, the correct BB spindle length depends on the diameter of the seat tube, which you did not provide.

calvin17d

I know what youre talking about I read it on a retailers site. Doesnt this only pertain to Triple Cranks? This one is a Double. Outside diameter?

AEO

what about your chainline and chainstay clearance?

calvin17d

I have a aftermarket free hub that I can adjust with spacers. Also this bike is rocking some 1970's Nervar crank arms that are absolutely straight. It has plenty of clearance. I dont think I'll have a problem in that dept.

ldmataya 

I assume this is a square taper Centaur, not the newer ultra-torque. In that case, they used the very common 111mm AC-H bottom bracket. Easy to get from a retailer, cheap, and very reliable.

calvin17d

Yes this is a square taper. So I currently have a double Crank on my single speed and the chainline measures the standard 43.5mm for a double ring. So if im simply putting a new crank(double) that follows the same 43.5mm standard shouldn't my chainline remain straight if I use the prescribed 110mm spindle? I guess now im assuming that spindle lengths help to maintain a chainline standard.....?

ldmataya 

Yes. going from memory here, but campy doubles also follow the 43.5 chainline spec using their BB - so you would supposedly get the same chainline.

Spindle lengths certainly determine chainline. But there are other factors that can get in the way when you switch cranks. For example, there is no particular standard on q-factor or crank width. I've had "standard" modern cranks rub on supposedly modern frames (chainstay rub) when installed with their matching BB. Chainline was fine, but everything else was different.

calvin17d

Many thanks

calvin17d

Got the new Campy Centaur Double Crank arms with an Origin 8 Chainring. This application calls for a 111mm spindle. This size spindle is only made by Campy or phil wood from what I have found. Both are very expensive. I will be running this on a conversion, how horrible would it be to run the shimano 110 or even a 112 that cost 19 bucks. I just cant see spending that much on a BB for a conversion. If I do go with a 1mm increase or decrease what kind of mods can I make to compensate? Thanks to all!

operator

Spindle length is not directly comparable from ISO to JIS bb's. Meaning a 110 JIS bb does not give you the same chainline as a 110 ISO bb, given the same crank. ISO crank on a JIS spindle = 4.5mm out, according to sheldon brown.

Meaning crank spec'ed for an ISO 111bb = a 107mm JIS should be used to get the same chainilne.

At any rate there are plenty of low cost campy square taper bb's. The low-end camp one retails for $20. I wouldn't exactly call this expensive.

DaveSSS 

In addition to the chainline problem, using a larger JIS taper will not permit the crank to fit as onto the taper. I know people do it, but it's not ideal. Both tapers have the same angle, but the JIS is larger at the small end.