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Calnago
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by Calnago on Tue May 03, 2016 3:32 am
Well that's an entirely different beast than what I looked at. Are those Delrin cups holding everything together? Without slighting their product, as I've never used it, it seems to me that that system is introducing a whole bunch more interfacing surfaces that could be the source of creaking. You've got the outer surface of the cup against both the inner diameter of the shell, and the flange against the outer face of the shell. Then inside you have the bearings themselves against the inner surfaces of cups and then finally the inner diameter of the bearings against the spindle. Then you still have to make sure the two separate cups are aligned with each other. Aach!
I think Trek has done an amazing job on their newest BB90 shells to ensure that the tolerances are round and tight and square. Now that I've seen that pic (thanks for the link) I would really recommend going the simple route with just two standard bearings and their seals, then slide the crank through. As for preload, I know Shimano says to just go "fingertight" but sometimes that doesn't seem to be enough to really move it. I have a Park Tool BBT-9 that (with a 4mm Allen wrench) allows me to get that little "help" I might need. You certainly don't want to over tighten but you do just want to get it on enough so there's no lateral play in the crank. Good luck.
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nemeseri
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by nemeseri on Tue May 03, 2016 4:57 am
Calnago wrote:Well that's an entirely different beast than what I looked at. Are those Delrin cups holding everything together?
It looks tricky. It's a combined design that they use for BB86. If you want to use it in a BB90 you can remove just the bearings and the seals together and install them without the cups.. So it's not a bad design I think.
I also had great experience with my trek so far. If I didn't have terrible experience with LBSes I'd probably simply give up and hand it over to them. On the other hand this way probably I will finally learn how to properly service my BB. So I will keep trying.
Thanks for the tip on the preload! I will try to tighten it a little bit more and make sure the cranks are turning without any problem. That's easy to try so let's see. Thanks for the tips again!
