I've been looking but can't figure out what tool I need to get to replace my BB. I pulled a crankarm off the bike and verified it's an ISIS drive, but after that... I don't know what I'm looking for. I wasn't bright enough to measure the diam of the lockring. Do I just need to count the number of indents around the lockring? I'm confused, as most ISIS bottom brackets come up a different set of splines than what I have.

Sorry for the bad pic, I was rushing while working last night. I remembered to take a pic but didn't do that before cleaning things up (not sure why!).

Soap and water and a scrub brush. First!

Its covered with crud, and who can see past the dirt?

You sure it's not a Shimano Octolink splined BB?

Personally--no idea, not a bike mechanic. Looking at Sheldon's site and elsewhere, it looks like an ISIS drive. Octalink doesn't spline the full length. I did something about 8 and 10 spline versions of... something, already forgot.

I do know the BB is hollow, and it's a 3 piece crank setup.

Edit: thanks for posting the pic, darn work filters block tinypic on me.

It looks like ISIS. I use the Park BBT-22 and I know its good for both Octalink and ISIS bottom brackets. But your pic throws me off in that I don't see the typical lockring with the splines going inward. Color me confused. Would be curious as to what the other side of the BB looks like...

Edit: I guess ISIS also comes in a version that use a traditional pin wrench lockrings:



I learn something new every day...

If they spent the big bucks for those SKF , no bikes don't come with them, I Expect they'd know.

Yes , Octalink splines are squared off..

Nope, it has 10 splines. Octalinks have (wait for it.....) 8 splines.

Nashbar ISIS Bottom Bracket

Got other side off. 8 indents, 40mm OD.





Ah, ok, once I get that outer lockring off, then I should see splines behind that. Got it. I couldn't figure out why I couldn't see the splines on the ISIS bottom brackets that I could find, have to get the lockring off first, then I can get to it.

While on the subject... looks like the same tool required here. Same 40mm OD on the lockring. But on this bike, what are the two dots on the crankarm bolt? Is this a self extracting crank arm? It's 2007-ish Ultegra. I thought of pulling it but decided I didn't need to at this time.

Missed this post. Ok, I wondered when I saw the setup if it might be old-school--I did mess with the cup and cone BB on my Raleigh, so I know the tool you are talking about. Of course I don't have that one... but your pic does look a lot like what I have.

Of course mine is kinda screwy, it has an oring on it, that does nothing, seemingly. I was able to easily pry it off. Seems odd that it doesn't bottom out. [The red bike does not use this o-ring setup.]



Edit: o-ring sits in the groove here; I pried it out for this photo. It basically fills in the groove for aesthetics I'm guessing.

Yes, Ultegra Octalink cranks had self extraction crankarm bolts. Back off the bolt with a 8 mm hex key and after it turns a rotation or so it gets tight again. Continue unscrewing the bolt and the arm will come right off.

DO NOT try to use a traditional pin wrench to remove those ISIS bottom bracket cups. They are aluminum and installed much tighter than a traditional cup and cone BB lockring would be. You'll destroy them quickly. Buy the right tool for the job. Unfortunately, for some unknown reason Park Tool, whose tools I can usually trust, makes a god-awful 8-pin tool for this job. Don't waste your money on it. Get this one and be done with it: Truvativ Isis Drive BB Tool > Accessories > Tools & Maintenance > Bottom Bracket Tools | Jenson USA

That's not a lockring. It's the bottom bracket cup itself, but with an 8-notch pattern that Truvativ and a few others used for the short time that ISIS was around. See my other post for the tool you'll want to remove those cups. Don't bother with anything else as you'll just make your life harder. Trust me.

A few people have mentioned splined bottom bracket cups which some vendors, like FSA, did use with their ISIS BBs.

Thanks for the warning. I'm used to the splined Shimano style lock rings. [MENTION=152773]noglider[/MENTION] pointed me to a tool to hold the Park BBT-2 tool on and works like a charm.

FWIW, you really need a dedicated 8mm hex tool on a 3/8" ratchet wrench to get these off. I found out the hard way that my Harbor Freight 8mm ball end t-handle was not up to the job.

And Hexalink would have six splines!!!

An extra-long hex key can do the trick, but a 8mm hex socket is preferable. Those bolts get ~30 ft. lbs. so you need more than a few inches of leverage if you expect to loosen them.

Thanks! I will get that tool, when I need to.