Noise problem after tune-up

[sldavis447]

I have a Giant Cypress LX that has just recently developed a problem. Part of the problem is that it only started happening after a rather expensive tune-up at a local shop. The tune-up and associated parts replacement seem to be working well. The bike shifts better, etc. after the tune-up. The problem is this...

It now has a very distinctive and annoying noise emanating from the rear wheel. The noise is a sort of grinding that occurs once each rotation of the wheel. If I lift the bike off the ground and spin the wheel, there is no noise. If I'm riding it with my full weight normally distributed, it makes the noise. But if I put my weight way forward over the handlebars, the noise stops. I don't have to be sitting on the seat. If I stand on the pedals, the noise is there as long as I don't move my weight way forward.

Here's where it gets really frustrating...Murphy's Law type frustrating. I mounted the bike on my bike rack and drove to the bike shop. I pulled the bike off the rack and rode it a bit before taking it in the shop. You guessed it...no noise. Argh!! I took the bike in the shop and described it to one of the techs. He rode the bike and also no noise. He said he believed me and took a good look at the bike and made some adjustments. Then a little test drive outside the shop and no noise, just like before taking it in the shop. So I load it up and drive home. I unload the bike, get on it to take a quick spin and guess what...it's so obvious...the noise is back again.

So I'm just wondering if any of you folks out there have any idea what might cause the noise I've described? My backup plan is to see if I can find a bike shop that makes house calls. I don't want to take the chance of dragging the bike into a shop and having the same thing happen. It it did, I'm afraid I'd just toss the bike into a dumpster and take up skating. LOL!!

Any input appreciated.

 

[Germanrazor]

Frustrating yes! I cannot even begin to say what it may be as I am not there and who is to say it could be diagnosed. Had a Toyota Avalon brand spanking new that the wireless trunk release when at home would not work to save your life. Drove it to the dealer and worked every press of the button :O

Get home, will not work again! Dealer replaces lock system latch. Works at dealer and should at home. Get home, WON’T WORK!!!!! A month later rear ended at 50 mph and the trunk is in the back seat......problem fixed!

 

[Mr. Beanz]

I'd guess that they trued or added tension to your wheel and got a spoke to bind up.

First off, there is a reason I don't let the shop mechanics tough my bike. I had this many times before with the "free" tune up that has cost me in wheel damage and repair. Second off, many of the guys that work in bike shops are not actually WHEEL guys.

So, when I build my wheels (I started after the shops started screwing up my wheels), I place a black mark on the spokes with a marker. Some people use a tape flag on the spoke. I have done so when a job only requires 4 or 5 spokes.

When I go to turn a nipple to tighten a spoke, I keep my eye on the black dot as I turn the spoke wrench to verify that the spoke does not twist. Or make sure the tape flag does no turn if using tape.

I have watched the mechanics do the FREE 90 day tuneup on my bikes and have never seen one pay attention to this, or mark the spoke. One guy did tell me that he uses some kind of pliers to make sure the spoke doesn't twist. 1 out of 20 maybe. (been riding for 25 years).

Now if you have stock wheels, they were probably built with some kind of thread lock, thread solution of something. So if the dude trued your wheel to make it straight, I'd bet he didn't do anything to loosen the connection between the spoke and nipple. SO there is a binding, the spoke twisted as he turned the nipple.

After a couple of the last incompetent mechanics did so on my wheels, I loosened the spokes, marked them, then set the tension properly myself making sure that I did not bind any spokes.

In short, I bet they trued your wheels and caused some binding on a spoke or two. Only way to fix it is find which spoke makes the noise and loosen it to let the spoke relax back into place. Then tighten while monitoring with the black mark to verify the spoke does not spin while turning the nipple.

You might be able to take it back and explain that they may have caused binding on a spoke or two while tightening the nipples.