What bottom bracket...
 

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[Closed] What bottom bracket do I need?

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A ridiculous question you would think, but here I am confused by the variety of BB's currently available.

I have a 2011 Stumpjumper Evo and my BB turned to mush. Now I thought I had a BB30 (this is what's written on the cranks and I've actually heard of it) but according to some people I have a PF30. What's the difference? Why do they look the same?

This is mine;
[img] [/img]

The only one I can find that looks the same is this;
[url= http://www.chainreactioncycles.com/Models.aspx?ModelID=55293 ]SRAM BB92[/url]

But what does BB92 refer to?

You can even get a BB91!;
[url= http://www.chainreactioncycles.com/Models.aspx?ModelID=44225 ]Shimano BB91[/url]

But will the Shimano BB fit my Sram carbon cranks?

My head hurts. Please somebody just tell me where to click and what to buy!


 
Posted : 25/11/2012 5:09 pm
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It is press fit 30.BB30 bearings for a 30mm crank spindle but housed in plastic cups (instead of the bearings being pressed directly into the frame).
Your choices are sram-rubbish,fsa-slightly less rubbish and errr thats it (wheels mfg/ison excluded).
Shimano does'nt support 30mm standard
You can with a bit of know how just replace the bearings alone.
Otherwise
http://www.chainreactioncycles.com/Models.aspx?ModelID=51600
Edit..out of stock 🙁


 
Posted : 25/11/2012 5:18 pm
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Thanks for the explanation. Did you check the link to the BB92 I posted? If that will fit I'll get it. I know they're a bit weak but I need to get back out riding ASAP. You're right about there not being much choice, the only other ones are Sram ceramic bearings for £150.

I thought about replacing just the bearings but this was a few minutes after I murdered the cups.


 
Posted : 25/11/2012 5:32 pm
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BB92/91/86.5 are all for 24mm spindle cranks and wider,smaller dia bb shells.No joy.
If you struggle to find somewhere with them in stock on line I've got some at work I could post out.


 
Posted : 25/11/2012 5:36 pm
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The BB92 is for the stepped 24mm Sram axles, not 30mm.

You need a PF30 as Rorschach says.


 
Posted : 25/11/2012 5:37 pm
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Right thanks for that you've saved me some cash. I'll check in at the local shops tomorrow and get back to you if necessary.


 
Posted : 25/11/2012 5:37 pm
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It's a press fit bb30 but you can just buy bb30 bearings only and reuse the plastic press fit part


 
Posted : 25/11/2012 5:38 pm
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Not sure that's right - I thought PF30 bearings had a slightly smaller external diameter.

[url= http://www.bikerumor.com/2012/08/29/chris-king-unveils-disc-brake-road-hubs-pressfit-bbs-more/ ]Chris King[/url] apparently launching press fit BBs

Andy


 
Posted : 25/11/2012 6:06 pm
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Will this one do the trick? I've looked at so many BB's I'm now scared to order anything

[url= http://www.ebay.co.uk/itm/Sram-Truvativ-PRESSFIT-BB30-Bottom-Bracket-Bearings-/310498737275?pt=UK_sportsleisure_cycling_bikeparts_SR&hash=item484b2abc7b ]ebay link[/url]


 
Posted : 25/11/2012 7:07 pm
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OR...... You can, I believe, get inserts fitted into your BB30 shell, allowing a conventional HT2 BB to be fitted.


 
Posted : 25/11/2012 7:13 pm
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He's got bb30 cranks....don't confuse the poor mite anymore ffs!!
Aye, that's the badger.


 
Posted : 25/11/2012 7:16 pm
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But then I'd lose my posh cranks! Really like the cranks.
Next time I'll take care not to kill the cups and just keep some spare bearings in the tool box.

EDIT: beaten to it!


 
Posted : 25/11/2012 7:17 pm
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Just sayin, like!!!!!!!

I have to say, I know nobody pleased with their PFBB30 BB's. It would put me off a bike.


 
Posted : 25/11/2012 7:48 pm
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I have to say, I know nobody pleased with their PFBB30 BB's. It would put me off a bike.

I've got BB30 (rather than PF30) on two bikes (one carbon road, one alloy MTB, both Cannondales) and it's been fine. I did contrive to wash all the grease out of a set of bearings in three XC rides, though.


 
Posted : 25/11/2012 8:10 pm
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It's defo a P(ress)F(it)30, not BB30,BB86, BB91 or any other numbers. Like other people say, they're complete turd. unfortunately you don't have a lot of choice other than the Sram original so it's worth having a couple, 1 for the bike and 1 as a spare.


 
Posted : 25/11/2012 8:10 pm
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Thanks for the advice, I've heard nothing but bad things about these BB's. It's a shame because I love the bike it's amazing. First bike I've had for years that I haven't immediately wanted to sell and I've spent a fair bit on upgrades.
I think when I find the right BB I'll buy a couple to keep a spare.

Just to confirm, is this the one?
[url= http://www.ebay.co.uk/itm/Sram-Truvativ-PRESSFIT-BB30-Bottom-Bracket-Bearings-/310498737275?pt=UK_sportsleisure_cycling_bikeparts_SR&hash=item484b2abc7b ]ebay link[/url]

If it is I'll grab a couple.

cheers.


 
Posted : 25/11/2012 9:03 pm
 LeeW
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Praxis make what looks like a good solution to the BB/PF problem for Shimano cranks - I think they'll be making a Sram version soon. It looks like a std external BB with slits cut axially in the drive side end, you press the non drive side in then screw in the drive side.

As you screw the drive side in it opens up the BB, securing it in the frame.


 
Posted : 25/11/2012 9:27 pm

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