Do bearings ever get BONDED into rocker arms??

JimmerG

So, Ive a slightly ageing Trek Fuel Ex 5.5. (which I've owned from new)
It developed a bit of rear end play which I traced to wobbly frame bearings. Not the main chainstay/bottom bracket pivots, but the rocker above it. I bought new bearings that are categorically identical. Upon removing the old bearings I noticed a fair amount of hard glue had been used to 'Bond' the into the rocker arms. Having cleared this glue out, my new bearings seem decidedly loose. Indeed having put the frame back together, there is significant play as the bearings are actually not tight in the rocker arms.

My question is - is it normal to bond bearings into rocker arms to cut out any play. Can glue actually provide strong enough support in an area that gets so much pressure applied to it?

Thanks for your help.

James

nicklouse

A bearing fit can be used on some builds.

Eg http://www.toolstation.com/shop/p57787? ... 3godSF0AUw

mini_death

You may have heard of people using loctite 638, it's the same stuff but can be bloody expensive.

miceden

When you say "not tight" how not tight exactly? You can move the bearings around (side to side) by hand when they are seated in the rocker?

You're sure its not worn bushings? If you are positive not then it could be you need a new rocker... it should snuggly hold the bearings with no side to side play, a retaining compound may have been used to stop the bearing rotating in its seat but to take up side to side play I don't think so, that would be really sloppy machining.

Be careful what locative/retaining compound you use... some form a permanent bond, some take a lot of heat to remove, etc, you want a low or medium strength compound.

JimmerG

Thanks Chaps,

It seems this Loctite 638 stuff, IS what Trek use. Its claims to be able to fill gaps of .38mm which seems pretty clever to me.

So that sorts out my problems.

Thanks again.

J

miceden

That comes from Trek direct? Fair enough if that's what they do but I still think that's poor on their part.

.blitz

Yup the bearings on my Rize are held in place with Loctite 638 easy to remove using the mrs best hairdryer

Cromwell Tools sell small tubes https://www.cromwell.co.uk/LOC7255419F expensive but 3ml goes a long way

iwilldoit

I don't know if this would work for you but I have used Pacer bearing locking compound like Loctite but a hell of a lot cheaper and I have always had good results.