justinzane

So, a long while ago I picked up a 52-36 crankset with matching bottom bracket and my brain recorded it as having an English (BSA) BB. Then, my generous spouse got me a NOS Fuji Aloha frame with fork and headset for Christmas. Awesome, since I've already got the Syntace C2 aerobars that were part of the stock bike as well as derailleurs, brakes, etc.

As I was putting things together, I realized that what I thought was a BSA BB with the crankset was actually BB86. Doh!

So, given that the ISIS FAQ is not helpful, is there a BSA bottom bracket with ISIS splined axle that could be used with ISIS cranks on a bike with an English BB shell? ANSWER Yes, from Nashbar for 23.99.

Having answered my own question, I'm wondering if it is possible to simply replace the BB86 threaded rings with BSA rings using the same BB "core"?

dr_lha

Your post is pretty confusing, let me try to figure out what you want:

1. You have a frame with a standard BSA threaded bottom bracket shell, yes?

2. You have a crankset that came with a BB86 bottom bracket.

You want to put these parts together? The answer is you need to buy a BSA bottom bracket, like the Shimano BBR60 (if it's a Shimano Hollowtech II crankset).

https://www.amazon.com/Shimano-Ultegr.../dp/B00DR6CCIC

It's the mention of ISIS that confuses me. Where does this come in? ISIS cranks don't work with BB86 BBs. What crankset do you have?

justinzane

YES
YES It has ISIS splines as the interface between crank arms and spindle.
I think this was a garage sale or "$1.00 Box" type purchase. It is cheap but serviceable Origin8 crankset that I bought attached to an existing BB. The threads looked like BSA casually, but it is clearly labeled as BB86. And both are labelled ISIS drive.

dr_lha

FYI BB86 Bottom Brackets are press fit and don't have threads. Therefore it sounds to me like you have an ISIS crankset + bottom bracket, which would work fine with your frame.

fietsbob

More British Standard Coarse, BSC, than Birmingham Small Arms, BSA ..

dr_lha

It's funny how the names of these things stick around.

Slash5

Yes, I'm very confused. BB86 is a pressfit BB standard and doesn't even have a spindle.
As far as I know, ISIS was only ever available in BSA - or at least threaded. Not sure if it was ever available in other than British thread or not.

JanMM

Not every splined BB/crankset interface is ISIS. No interchangeability between the different types.
Just noted the link to ISIS FAQs refers to ISIS overdrive, which would be different than original ISIS, I think.
Lots of opportunities for confusion.

ISIS info from Sheldon:
Sheldon Brown's Bicycle Glossary I - K