Deore LX Hollowtech Wear

kona

Has anybody come across this before? I thought the bearings in my BB wear giving abit of play so I stripped it all down to see what the problem was, I came across something abit worrying and probably more expensive than a set of BB Bearings.

Shimano seem to have plated a harder metal on to the contact surfaces of the Crank axle, I have no Idea what it is but It seems to be of poor.

The areas concerned are in the red boxes, the wear is on the L/H side (Right hand in foto) just behind the splines for the crank. You can see the wear on the axle, in contrast the R/H side is unworn and serviceable. The material was actually peeling off, so its not like it was even manufactured to a acceptable standard IMO.



A closer view:



Bearing in mind that the BB was assembled correctley and any contact surfaces had grease on them.

Any thoughts? Incidentally, the play has gone after re-assembly. So I suspect the play may have been the L/H crank working its way loose.

Cranks are around 3 years old and have god knows how many miles on them, probably 3K or so.

CheGuedara

Jeebus - never seen that on a set of hollowtech cranks before!

Have the same cranks on my MTB - will keep an eye on them to see if the same thing happens (though I'm waaaay short of having 3000kms on it just yet)

kona

I know, Id say it could apply to all of the Hollowtech2 cranksets as Id imagine they all use the same design in this area. 3k is a guess off the top of my head , maybe more maybe less, I dont have a cycle comp so Ive no idea! Should really get one!

zil

I've got the same wear patterns on my axle. Was a bit worried when I first saw it but as soon as I replaced the BB the play disappeared so it doesn't seem to be effecting anything at the moment. If you follow up on this I'd be interested in hearing what the bike shop/shimano say to you about it.

kona

zil wrote: »

I've got the same wear patterns on my axle. Was a bit worried when I first saw it but as soon as I replaced the BB the play disappeared so it doesn't seem to be effecting anything at the moment. If you follow up on this I'd be interested in hearing what the bike shop/shimano say to you about it.

Ill email Madison and see what they have to say. There was play in the L/H crank and this may have contributed to it, I dont know how long the play was there as I only picked up on it on my monthly service, there was no signs of play while riding. Im not after a refund or new parts, as nice as it would be, they are 3 years old and Ive gotten fair use from them, I just feel this isnt really acceptable on parts such as LX.

doozerie

I've not used Hollowtech II myself but from reading through some *very* heated online discussions (cyclists and engineers, a match not made in heaven!), I've seen someone refer to what sounds like a similar issue and one theory suggested was that the BB faces might not have been faced properly. Someone mentioned a simple and quick knack for checking the facing - thread in an old cartridge bottom bracket and use feeler gauges to check for gaps between the oversized face of the b/b that bears against the face of the b/b shell.

kona

doozerie wrote: »

I've not used Hollowtech II myself but from reading through some *very* heated online discussions (cyclists and engineers, a match not made in heaven!), I've seen someone refer to what sounds like a similar issue and one theory suggested was that the BB faces might not have been faced properly. Someone mentioned a simple and quick knack for checking the facing - thread in an old cartridge bottom bracket and use feeler gauges to check for gaps between the oversized face of the b/b that bears against the face of the b/b shell.

Hummm It makes sense, but the frame was faced , However you would expect to find the same on the other side if it was the case. I'll Email Madison and shimano and see what the story is. Im sure they have come across it before.