noise in bottom bracket and possible through boom

[paulbostick]

Has anyone had problems with crankset loosing up.I have had my local repair shop break down bottom bracket twice regrease and assemble back torque all to specs. This will last for about two weeks of riding then play will come back in bottom bracket.This is a sram red crank and gxp bracket.There is very little play but enough to make popping noise.My repair shop says it is not in the crank or bottom bracket they appear fine not even a year old.Also have creaks that appear to come through the boom.

 

[Eric Winn]

Nothing like that for me. I'm

Nothing like that for me. I'm running SRAM Rival GXP on my Vendetta.

-Eric

 

[ratz]

Check the rings

Possible guess #1.....

Take the chain rings off and check if they are bent. Do they lay flat on the table or are they warped. If the are bent you get a left and right oscillating motion that can wiggle the crank are loose. Normally you can see it when you look at rotating. Usually find this post crash;

Guess #2 if the nose triangle of the Silvio isn't squared up and is twisted you could have the ring running as an angle that is creating lateral torque....


Weird problem let us know if you figure out the cause.

 

[John Tolhurst]

Is the pivot clamp tight,

Is the pivot clamp tight, have you checked those bolts and the slider clamp? If you place a washer between the pivot clamp and the slider clamp and thread the connecting bolt through this washer, it will ensure the slider clamp is not knocking laterally against the pivot clamp. If that takes the noise away then you know that a o-ring might solve the problem. (You can't leave the washer as the slider clamp may not be gripping the slider properly with it in place.)

 

[John Tolhurst]

If you can rebuild and its

If you can rebuild and its okay only for later this noise to return, then It is essential that when you disassemble you test each threaded item to see if it has retained its torque setting. Otherwise, how is one to diagnose remotely? Before and after the rebuild, something is different. What is it? Could it be the BB ring clamps on the BB shells somehow working the shells loose? So, is it the shells which come loose or something else? Need data.

 

[paulbostick]

bottom bracket

It is the bottom bracket .You can grab both crank arms and pull back and forth and feel the play.Bottom bracket ring clamps are good and tight.He is going to check every spec when he breaks it down tommorow.

 

[John Tolhurst]

its natural when issues arise

its natural when issues arise that they are associated with this 'new fangled thang'. Often they are. And sometimes not. We've spent a lot of time assuming responsibility for this diagnosis here and elsewhere, so, ah hmm ... to whom do I send the invoice?

Just kidding!

As the great Buckminster Fuller said (I think) whatever you do, you can't learn less, you can only learn more.

I want to hear what we can learn from this as its a quite unusual one and I want to be sure whether our design is related in any way.

 

[thaddeus]

Try this ?

http://cruzbike.com/creak-solved