Advice on loose bearings in Trek Madone (BB90)

osse

New Member
Hi, first time poster

Some time ago my bike bike produced a creak that I determined was caused by loose BB bearings on my Trek Madone 9.5. Long story short: I got a replacement frame, in the form of a Madone SLR (yaay, free upgrade).

Recently I've noticed a small clicking sound when I pedal hard, and I remember from my previous encounter that it starts as an innocent-sounding click that occurs only every so often but evolves into a loud crack that makes me worried the frame with snap right in two under me.

I removed the crank, and lo and behold, *both* bearings are loose! See this video (the behaviour is identical on the non-drive side). At this point I've ridden the bike less than 200 km. I'm baffled and confused at (seemingly) how little the frame can handle.

One obvious question: Are the bearings in fact loose or is that just some sort of plastic cap I'm have a tug of war with? What you see is how loose they get; it's not like they fall out or anything. I did not do this inspection immediately after picking up my replacement build so I don't know how it looked brand spanking new.

Secondly, could this somehow be my fault, because of my riding style? Due to a slight handicap my left leg is way stronger than my right, which potentially means one side of the bike is stressed harder than the other. If you're puzzled and amused, note that it's not like my left leg is super-human; it's just that my right is weak. So if anything the bike experiences less stress in total.

Lastly, could this somehow be my fault, since I managed to let the bike fall on its side? The wind caught my bike during a break on a longer ride and it fell onto its drive side. The handlebar tape tells me that the handlebars took some of the fall and I wasn't on it at the time. The frame didn't touch the ground at all, as far as I can tell. But the right pedal did... Could this shake of the crank cause it? Is the BB really that brittle? It was immediately after this I first noticed the sounds, but that might as well because I've become a nerve wreck after the long story I made short in the beginning.

Any advice appreciated. I can of course film some more or take pictures if that helps! My LBS has been wonderful in handling the warranty stuff on the previous frame, but now I'm starting to doubt myself and would like a second opinion.

Thanks, Øsse
 

Darius_Jedburgh

Looking for the lost chord.
Hard to tell from that video if the bearings are loose in the frame or if the bearings are shot.
 

Cycleops

Legendary Member
Location
Accra, Ghana
As above difficult to tell which. I should refer back to your supplying dealer, your contract is with them. Don't try messing about with the Hambini kit in the video which would invalidate your Trek warranty.
Press fit bearings are the work of beelzibub himself so let your dealer sort it.
 
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boydj

Guru
Location
Paisley
Well he's been on and not replied. If this is as big a problem as he claims then he would have looked to see what the advice was.
Otherwise we must think that he is spamming bike sites until he gets an answer that suits him then disappear.
You don't know where he's located, if he's at home or working, or in bed fast asleep. If he's interested in replies he'll be back when he's ready. Give him a chance - we can't all sit for hours waiting for replies.
 
OP doesn't seem too interested in our help.
Another one hit wonder?
Not a very helpful comment to a new member
:whistle:
 

si_c

Guru
Location
Wirral
Creaks can come from anywhere, I wouldn't jump to any conclusions. Also that video linked appears to be a delrin cap/spacer over the top of the bearings and not the bearings themselves.
 
OP
osse

osse

New Member
Thanks, guys.

The reason I haven't replied yet is because I haven't checked. I just assumed I wouldn't get replies that fast and in my experience I have to actively turn off email notifications on replies in most forums. Sorry...

Hard to tell from that video if the bearings are loose in the frame or if the bearings are shot.
"Shot" meaning they don't rotate properly? I will double check that, but I'm fairly sure they spin just fine. The crank spins fairly smoothly after installing.

As above difficult to tell which. I should refer back to your supplying dealer, your contract is with them. Don't try messing about with the Hambini kit in the video which would invalidate your Trek warranty.
Press fit bearings are the work of beelzibub himself so let your dealer sort it.
How can I make it easier to tell? Oops, I already bought a kit in a heated moment. I will anyway contact the dealer first (unless you guys told me"Oh, that is completely normal"). They have given me a new frame once before. Maybe they'll do it again and I get the new model with T47 instead :-) A scenario in which I simply keep the bearings from the kit as overly expensive fidget spinners would be a welcome one. My main concern now is whether it's realistic that the minor fall could somehow cause the problem and/or void the warranty.

Creaks can come from anywhere, I wouldn't jump to any conclusions. Also that video linked appears to be a delrin cap/spacer over the top of the bearings and not the bearings themselves.
I forgot to mention it in the original post, but when this happened the first time the symptoms were exactly the same as now, i.e. I could rock the bearing back and forth slightly with just my finger. I tried all sorts of things then: I rode with and without my usual shoes, I switched pedals, I switched the whole crank, double-checked the rear mech and hanger and cleaned it, and rode without a seat-post with no difference in behaviour. I can of course doublecheck this, and I will, but the observed symptoms are so far identical, so I wanted to try get opinions on whether it's likely that this is (still) the problem. There is one thing I haven't checked because I didn't think of it: the spokes.

As for the delrin cap. Do you have any advice on how I can confirm this? Should I e.g. be able to pry it off with a flat head screwdriver, a knife or something like that?

Thanks! Those dust covers on the new bearings of his look very much like the ones that are install on my bike. Maybe it's only those that are loose and the bearings themselves are properly seated.
 
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