Help please! Bottom bracket wave washer replacement ????

[thismonkeyhere]

Hi, long story short, pedal crank bolt (non drive side) loosened and came off during a ride. Gathered up bits and got home, but think I have lost a wave / spring washer between crank and bearing. Didn't look hard for it, largely because I didn't know there was one there in the first place. Now have lateral movement (only about 1, maybe 1.5 mm) and bolt won't stay tightened. Can't get any clarity on what washer I need to get to replace (or if there was also a shim, which I doubt due to the small amount of movement). Any help navigating this gratefully received - need to get it fixed as it may be the only thing between me and middle age spread under current circumstances!!

Bike is a Specialized Diverge with an FSA Gossamer crankset.

[Your Dad]

Probably part MW454 - FSA wavewasher for 24mm spindle MegaExo.

Try ebay.

[thismonkeyhere]

Your Dad said:

Probably part MW454 - FSA wavewasher for 24mm spindle MegaExo.

Try ebay.

Can't find a MW454. Would the MW120 do the job? Also 24mm?

[JEA1K]

Top search on google

https://www.bike24.com/p2321258.html

[thismonkeyhere]

JEA1K said:

Top search on google

https://www.bike24.com/p2321258.html

Thanks. Doesn't appear at all on a bing search.

Seen any uk suppliers? MW-120 seems to have the exact same description, just a different number.

[moonigan]

Is this the bike or similar? https://www.specialized.com/us/en/diverge-comp-dsw...

If so its a BB30 bottom bracket so you could either buy the bearing replacement kit which has everything in it: https://www.wiggle.co.uk/sram-bb30-standard-bearin...

or just the wavy washers from any one of these: https://www.google.co.uk/search?q=bb30+wave+washer...

P

[gazza285]

I had the same problem on my ‘cross bike, the only permanent cure I found to the crank bolt coming loose was to throw the FSA crap in the bin, and replace it with a 105 crankset.

[Your Dad]

moonigan said:

Is this the bike or similar? https://www.specialized.com/us/en/diverge-comp-dsw...

If so its a BB30 bottom bracket so you could either buy the bearing replacement kit which has everything in it: https://www.wiggle.co.uk/sram-bb30-standard-bearin...

or just the wavy washers from any one of these: https://www.google.co.uk/search?q=bb30+wave+washer...

P

FSA spindle is either 19mm or 24mm, so a BB for a 30mm spindle (SRAM) is not compatible.

[lufbramatt]

FSA do BB30 stuff too.

If its a 30mm spindle I probably have a spare one in the garage I can stick in the post.

[moonigan]

lufbramatt said:

FSA do BB30 stuff too.

If its a 30mm spindle I probably have a spare one in the garage I can stick in the post.

This. The bike linked has a FSA Gossamer like the OP mentioned and its clearly a BB30. I also had FSA BB30 on both my CAAD10s one with a Gossamer crankset and the other with the carbon one.

[Your Dad]

moonigan said:

This. The bike linked has a FSA Gossamer like the OP mentioned and its clearly a BB30. I also had FSA BB30 on both my CAAD10s one with a Gossamer crankset and the other with the carbon one.

This one also has FSA chainset but is threaded BB - https://www.specialized.com/dk/en/diverge-a1/p/128...

Op needs to confirm model & year of bike otherwise we're all just taking wild guesses.

[lufbramatt]

Also the crank bolt on those cranksets has to be pretty tight (by bike standards, something like 48NM). stick some threadlock on it too. I've not had any issues with the BB30 BB on my Cannondale in the 6 years I've owned the bike, maybe I got lucky and got one that was machined within tolerance.