dennis336

Looking for some help diagnosing a noise problem I'm hearing on my Surly Disc Trucker. I'm hearing a squeaking/squealing noise -I think coming from the rear of the bike when I rock the bike left and right (vs rolling it forward and back). There will be some squeaking when I roll it forward and back but it seems louder when rocking left/right. It sounds like the noise you often hear when braking with disc brakes. In the past, the disc brakes had been pretty noisy while braking but I cleaned them and that was a big help in reducing the noise when braking (not completely gone, particularly if the roads are wet but a big improvement from what it was before cleaning). Not sure I can make a direct connection with the noise I'm hearing now when I rock the bike back and forth and when I cleaned the brakes but I suppose there could be something there from when I re-installed the pads (first time doing it and I'm not real good mechanically). What seems odd is I don't hear the noise while riding without braking and only periodically when braking.

Some added info, may not be relevant ... it's a steel frame and I keep it in my garage so it's fairly cold although not exposed to the elements.

Any thoughts on what could be causing that noise? Thanks in advance.

Andrew R Stewart 

If you can detach the brake cables and thus have zero pad/rotor contact and the noise is still there I'd look next at the hub seals and pulley wheels. Andy

dennis336

Thanks for the ideas - I played around some with the tension on the calipers (right term?) to open up the pads a bit more from the rotor. Seems like some initial improvement, although noises have a way of coming back so I'll continue to monitor. Thanks again for taking the time to respond!

WizardOfBoz

My front wheel would squeak if I turned or really graunched down on the crank. I finally determined that if the wheel wasn't fully seated in the fork, and the quick release was too loose, I'd get the sound. So now I make sure that the QR is snug when tight, and I only tighten it when the bike is on the ground, resting on the wheel. Works for me pretty well.

Le Mechanic

Always check the easy stuff first.

Wattsup

Try this. Hold a little brake in while doing the rocking and rolling, enough to have the pads press the discs, but not so hard that the wheel won't move. If the noise disappears when doing this, then it was definitely the pads causing the original noise.

dennis336

Thanks all for the tips. I tried opening up the calipers to give a bit more space between the rotor and pads and that seemed to work. Should have thought of it right from the start but when the squeaking largely went away when actually braking after I cleaned the pads didn't occur to me that the sound might occur in a different scenario. So, fingers crossed, the sounds will stay away. Thanks again for the diagnosis tips - really appreciate people taking the time to respond.

Phil_gretz

Not so fast. Did you check for play in the rear axle bearing adjustment? That could be your source of side-to-side motion in the rear rotor, the hub moving laterally on its axle. Check the cones...

dennis336

Phil, thanks for following up. I just checked the rear rotor/hub and it seems to be secure. I'll continue to monitor it. Thanks again for the advice.