Power Spline BB. Upgrade to outboard bearing BB?
 

What kind of bottom bracket is this?... and what are good options for a replacement?

The not-so-helpful website for Specialized lists my bike as "ROUBAIX ELITE SL2 APEX COMPACT", and under the spec page it lists:
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I'd prefer if it told me what kind of BB.

Pic:
EDIT: I changed the thread title, to help anyone who searches this topic in the future.

Looks like ISIS.

Looks like a Isis or Shimano Octalink splined BB with threaded 68 mm BSA shell. Being Specialized, it is not Italian sized. I'm no expert on what Specialized uses for this type of BB, their own version or one of the OEMs.

It is isis .

+1 That's what it is.

Thanks!

I'm looking at ISIS BBs online, and they all show a lock-ring or flange:

On the right-hand side in this pic:
My bike doesn't appear to have a lockring/flange, on either side. the drive-side look the same as the pic I posted above.

Also, are there any "good" replacements you'd recommend? "Good" meaning "better or lighter than stock".

My drive-side:

Have your pick ,any will work ,just name your price . http://www.amazon.com/s?ie=UTF8&page...ttom%20bracket

Raceface, FSA, truvativ and others make ISIS splined BBs for relatively little money. Find one with correct spindle length for your cranks and you are good to go. For truvativ you will need a different BB tool than for the one you have because truvativ uses a different cup design than the others.

I would recommend you look for good quality rather than light weight. A quick scan of weightweenies.starbike.com indicates that you are likely to save around 50 grams at best, or about 2 ounces.

It's not a lock ring, it's a flange on fixed side to ensure proper installation. It's not completely necessary but helpful. See attached section on cartridge BBs for more explanation.

http://en.wikibooks.org/wiki/Bicycle...acket_overhaul

Bikeman, thanks for the link. From looking at the shopping options, (and my drive-side pic) I realize I have "Power Spline" BB. which looks different than ISIS.

DOD, thanks for the warning about the tool, and info on installation. I must be wrong about what I think I'm seeing on the drive-side.


cny, I appreciate the advice (I'm also in CNY, as you may have guessed!).

I would recommend you look for good quality and durability rather than light weight. A quick scan of weightweenies.starbike.com indicates that you are likely to save around 50 grams at best, or about 2 ounces. Best to look at a lot of reviews on various sites for what works best for folks.

oops, you are correct, taking a second look at your original pic. ISIS has 10 splines, power spline has 12.

This blows....

I wish I knew more about this (and my options) when I bought the bike.


I found more info about this (with pics) here:

http://www.bikeforums.net/showthread...-Apex-to-Rival

I may let this BB go until it turns to crap, then look at an upgrade of the BB and crankset.

Well that's an option. So long as the cranks are in decent shape, you could just replace the BB for very little money. Once you decide t0 get a new crankset, including the corresponding BB doesn't add appreciably to the cost. For example, on Amazon right now you could get a very nice Ultegra crankset for 200-250 bucks and the corresponding BB would run under 30.00.

Thanks, DOS.

I came back to answer some of my own questions....

I took the whole thing apart, and found what we figured was going on... Power Spline, with flange on drive-side:

For a compact crank, 1,040 grams (including BB) seems like something worthy of an upgrade when the time comes. I already have 4,000+ miles on this... maybe I can convince myself the time has already come.


I installed a GXP BB crankset I have lying around. Chainline is perfect. The pedals sit inboard a little more than my current setup, but that is not a problem. I guess I'll be on the lookout for a compact-crank GXP set. Hmmm.... I could also go for the Octalink, as you mentioned, too.

For Pete's sake... how much do you weigh if 2 lbs is so much?

It hasn't.

I'd go with an external BB crank upgrade. Nashbar usually has some FSA compact double cranks for around $120 and that includes the external BB with the kit. I see nice NIB and hardly-used external BB cranksets at swaps for less than that. Saw a couple of Ultegra compact doubles for $80. A very nice price and the weight savings for one of those over that boat-anchor you have there is a ton. It's only 897g. The Ultegra compact is around 700g. [TABLE="width: 100%"]
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Cambria Bike had a bunch of RaceFace Cadence cranksets with external bottom bracket for like $75 if you don't want a compact. It's a nice crank but the bottom bracket thast comes with the kit is so-so.

What's funny is that this whole thing started in my mind because I thought I had a BB30 frame. I never looked closely, and just ordered BB30 bearings, and a bearing tool.

I just never even looked, even though I've had the bike for a couple of years. I remembered discussing BB30 in the shop when shopping, and that stuck in my mind.

Since then, I've heard less-than–wonderful things about BB30, and I had a creak of some sort at the end of last season.

I figured "what the heck, bearings are cheap, I like working on bikes, let me change the bearing.


That got me to this thread, and a case of unneeded-upgraditis.


Hahaha..... You would spend a bunch of your time if you posted this in every thread where someone wants to replace a component, and they were looking at lighter options, even if the rider's level of performance doesn't warrant the "upgrade".


Unless you are already running Super-Record/Dura-Ace/Red, it's always in the mind of some people, .....that the next time..... you might move "up". Effective marketing is effective.


Unfortunately for me, the marketing of nice bike-stuff is equally as effective as the marketing of fast-food. My job.... don't get carried away with either one!

If I had any of the non-ST BB's in my bike and they died I wouldn't spend another penny on them and just dump the crankset and go external. Harvest the rings if they are any good and dump the ringless crank on CL for whatever you can get out of it is my thought. I wouldn't spend another penny on any of the intermediate tech between square-taper and the Hollowtech external standard. Square taper will be around forever, like Astabula and cottered cranks. It'll be a vintage standard. But I don't want any of that ISIS/Octo/powerslime around. In 10 years it'll be forgotten IMHO. Dump it.

Amesja, I'm headed in the direction of upgrade, but I picked a BB that isn't a 'standard', and in 10 years may well be forgotten. MegaExo.

I got a reasonably good deal on an FSA K Force Light with ceramic BB on eBay....
http://bikeforums.net/attachment.php...hmentid=361722
Replacement BB cost almost as much as I paid for the crankset with BB and rings. :shock: fortunately, there are less expensive options, when the ceramics give up on me. Or, I could rebuild the BB instead of replacing it. It's not like these OEM crankset makers are actually making their own bearings.

I agree that in 10 years, MegaExo might be a thing no one supports. Heck, only FSA supports it now.

I'll add details to this thread, when the cranks arrive.


Silly me..... I go from ordering bearings I don't need, to ordering a crankset I really don't need! ;)

I'm fairly certain that you can substitute a regular Shimano Hollowtech BB for that MegaEXO unit. That is if MegaEXO is MegaEXO across the FSA product line and there aren't two different standards.

I have and FSA Gossamer MegaExo Triple Crankset that I picked up at Nashbar last year and I simply substituted a Shimano Dura-ace BB-7900 68mm External Bottom Bracket that picked up on Amazon for a little over $20 when they were on sale. It fit right in, although it was a little snugger fit it wasn't bad. Pops right in with a rubber mallet no problemo. I'm using the MegaEXO BB on my CX beater with an old weird Sugino crankset that they only made a few of. It's Hollowtech compatible too.

I've rigged up one of these out of parts and pieces of all the automotive & motorcycle bearing press kits I have. I can press out the bearings on the "do not disassemble" cups no problem. The basic Enduro sealed bearing replacement kit for external BB's is only $13.44 shipped. That's way cheaper than any square-taper cartridge BB you can buy.

I like the idea of just replacing the BEARINGS instead of a bunch of extra metal parts that are just wasted when a BB needs service.