Hi,

I need to replace the stock FSA Gossamer BB30 on my Caad9 because after 25,000 km...it's time to replace both rings.

I found that the SRAM S900 BB30 is currently on offer (£105!).

What bottom bracket do I need to buy? Do I need to buy BB30 bearings AND BB30 bottom bracket or are they included in the purchase of a bottom bracket? will the existing FSA bottom bracket work with the S900 or do I need to replace bearings/bottom bracket?

Sorry about the many questions, but I don't understand it...

if the bearings you have installed now are in good shape, you can just take the old crank out, and install the new one. the bearings should work fine with either crank (that is part of the BB30 standard). generally new bearings don't come with the cranks.

just to help you out with the details, in this case the "bottom bracket" is really only bearings and two circlips that are installed in the bb shell. I have never had to replace the circlips, but have had to replace several sets of bearings. if you need to replace the bearings, the correct tools are a must.

@motorthings: thanks! I suspect I should replace the bearings too then after so many kilometres...Whilst am at it.

So, if i buy the S900 BB30 plus a set of new BB30 bearings (any brand?), should be it? Shall I get the SRAM BB30 bearings then?

Thanks again

25,000km isn't so many that chainrings and bearings should be worn out.

Do the bearings feel worn? When you remove the crankset, fell how well the bearings spin. If they grind at all, replace them. If not, don't worry about it.

And you will need a bearing press to install the bearings if you plan to do it yourself.

if you do need bearings, the SRAM are good.

@topflightpro: thanks. I thought 25,000km were quite a few for a crankset/bb. Under normal circumstances, what sort of mileage can I expect out of this Gossamer?
The bearings don't feel worn, I was just thinking that if I'm replacing the crankset I might well replace bearings too...

@motorthings: thanks for the tip, if I need new bearings will buy the SRAM then.

Thanks to both: will post some high def pictures of the teeth/crankset, perhaps you can assess...To me the teeth look a bit sharp like shark's teeth...

As promised I took a few close-up pictures. I'd appreciate your opinions, do I need to replace the big ring/do the teeth look worn out? (Chain Reaction Cycles are giving away a complete SRAM S900 for around £110!). The FSA in the pictures has done around 25,000 km of London commuting and winter training (plus the odd criterium).

http://imageshack.us/g/856/fsa1.jpg/

that doesn't look so bad, but i have never been a fan of the way fsa rings/cranks shift in the first place. if you upgrade, i think you'll get a much better fd shift out of a sram crank with good rings, than you will out of the fsa gossamer. i went from a gossamer to Ultegra on my first road bike, and it was a HUGE improvement. Then I went to SRAM Red and it was even better than the Ultegra.

New cranks generally come with rings.

with 25000k, i was sure your pics were going to show some fried chainrings, but they look fine. maybe good for another 10 or 20,000. i bet youre pretty good about replacing your chain before it's too worn.
i'd replace the rings/crank mainly if i just felt like getting something new and fresh.

@thisisatest, motorthings: thanks both for the kind replies. I'm pleased about your comments! Given that right now my priority (on this bike) is to minimise cost/maximise reliability (as it's my commuting and training bike), I'll keep the stock FSA. Agree, I'm not a big fun of FSA kit. I'm quite old school about this, I'd rather leave it to the guys who can design a complete groupset (SRAM, Campagnolo, Shimano)rather than a company who can produce only certain parts.

I guess in 10/20k kms, when time comes, I'll replace it with a S900 (or Rival if I find a good deal).

Almost forgot, yes I replace the chain regularly, and clean it/lub it properly...I like cycling with a clean and smooth drivetrain given the amount of km I put in per year...I usually do 2 chains per cassette.

Thanks again for the kind replies.