Clicking frame
 

During my ride on Sunday, my bike (a 1996 Cannondale R500 with 7300 miles on the frame) developed a clicking sound near the bottom bracket. At first I thought it was the bracket, but once I got home and put it on my repair stand, I found that it sounds like it is coming from the frame a few inches up towards the handlebars from the bottom bracket. I inspected the area, but found no cracks.

I am planning on taking the bike to the local bike shop before I ride it again. I was hoping that maybe someone here had experienced something similiar. Since this is my first aluminum frame, is this normal when under moderate to high torque?

Thanks.

A cracked downtube could generate the sound you are hearing.

I just got a new TREK aluminum frame under warranty. I had a clicking sound driving me crazy. When I got it on my stand that only holds the seatpost you could reproduce the sound by moving the frame around. No cracks were visible.

Nice to get a brand spankin new ALPHA SLR frame to replace the standard aluminum frame that cracked:D

Two things to remember about aluminum frames:

1. They are extremely noisy when compared to steel.

2. They conduct sound extremely efficiently.

That means that some noise is inevitable. You can minimize this by greasing bolts and contact points [seatpost, saddle rails, stem/handlebar clamp, etc.] It also means that the noise can be comong from almost anywhere on the bike, but is being transmitted at equal volume to every other squeal and click The noise could be just as easily a loose chainring bolt transmitted through the BB and the frame, hup the downtube to your handlebars, or it could be the seatpost clamp moving against the saddle rails, or it could be a crack in the frame. lopcating the source of a noise in an aluminum frame is a lesson in frustration.

velocipedio is right. Aluminum has very different properties than steel and sometimes gives you problems.

In my case, the head mechanic at a very good bike shop in the area had attempted to put some loc-tite into the frame from the BB. He said most of the time you can cure the frame from clicking if you did this. But, there has to be a hole through the BB into the frame's innards to squirt the loc-tite through. My TREK didn't have the hole so they couldn't perform the loc-tite magic.

Since it was under warranty they shipped it to Wisconsin and it got replaced. If you have a warranty, work it. If not, maybe a tube of loc-tite isn't such a bad idea...:rolleyes:

Anybody ever try this? Did it work?