asking Nick
I wrote a letter to Nick this morning. I really hope he responds...
Actually, what I really hope for (beyond world peace) is a bottom bracket "standard" that is light, stiff, easy to understand and maintain and, most of all, is actually standard!
Hi Nick,
I need a comprehensive guide on BB30 maintenance.
I think we’re all very familiar with the chronic creak
potential of BB30, yet it seems to me there’s no reliable way of assuring that
(1) a newly installed crank won’t develop a creak and (2) the spacers and dust
covers have been installed properly such that the crank spins as freely as it
should and that, to the extent that one can expect, the bearings are protected
from contaminates.
My best success in installing BB30 cranks comes when I
install a new bottom bracket using a headset press, then install the
crank. As far as what to do about spacers and dust covers, it all seems
like so much guess work, so, I guess, and usually (I think) things have worked
out ok. However, the real trouble comes when a crank has to be pulled
(for, say, sending a Quarq to be serviced, or simply moving the crank to
another bike) and those pesky bottom bracket cups stay with the crank spindle
rather than in the frame. Of course, getting a BB30 crank out of the
frame is a taxing and stressful experience in and of itself, but beyond that,
in my experience, there’s no “good” way to remove a BB30 bottom bracket bearing
race from a crank spindle without _feeling_ like the integrity of the
bearings have been compromised. (I recently saw a tool made for this
purpose with a Specialized stamp on it, though I haven’t been able to
experiment with it yet.) So when I have to pull a crank and reinstall it,
I leave the bearing race on the crank, but it seems that when I do that a creak
_always_ develops after a few hours of riding, even when using Loctite
to secure the bearing race, as per the recommendations of Specialized and Park
Tool.
I’m coming to the conclusion that I should consider BB30
bottom brackets as one-and-done installations. In other words, if it
crank has to be pulled for any reason, I might as well discard the bottom
bracket. This frustrates me on several levels, and I really don’t want it
to be true.
On the second point, regarding when and how to use spacers
and dust covers, I’ve found the documentation that accompanies a SRAM BB30
bottom bracket to be completely unintelligible. Sometimes I finish an
installation and notice a bit of spindle (maybe 1 mm) hanging out of the
frame’s bottom bracket shell in a most disconcerting manner. But, if
there’s no creak, I’m super hesitant to pull the crank and experiment with
possible solutions because (1) it’s damn hard, (2) the aforementioned concerns
about bearing integrity, and (3) if the thing’s not creaking, I don’t want to
change anything!
So, your thoughts? Secrets? Basic (and
not-so-basic) dos and don’ts of BB30 care and feeding?
If it matters, I’ve been sweating over BB30 bottom brackets
for nearly four years with varying levels of success on two different Tarmac
SL2 S-Works, a Crux, and a CAAD9 CX, all with Specialized S-Works
cranksets. (I’ve also a Stumpjumper with a press fit BB30, which fortunately
has had no creaking issues, but when it comes time to replace the bottom
bracket, I’ve no idea how that sucker is coming out.)
Thank you,
Nathan
If any of the two people that read my blog have any hints, I'd love to hear them.
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