Squeal

If the squeal does not happen when the bike is off the trainer, maybe the trainer itself is making
the noise, or the rubber of the tire is squealing at the point of contact. When you change gears,
you change the torque at the contact point and that could increase or decrease the noise. If the
gear sprockets are badly scalloped you should probablyb change out the drivetrain anyway.

r.b.

"j morelstein" <[email hidden]> wrote in message
news:<[email hidden]>...

Quoted message said:

I have a fairly old (8 years or so) specialized Allez with a Shimano 105 drivetrain which I now
use exclusively on my trainer. The drivetrain has about 10,000 miles of use on it. Lately I have
been getting a squeal (high pitched screech) when I use the bike on the trainer, particularly when
I am using certain cogs. Any views on how to fix the problem? Replace cogs (entire freewheel at
this point I guess)? Do I need to also replace the chain and the chainrings? Or could the squeal
be coming from the rear hub? It's hard to isolate the sound?

"j morelstein" wrote

Quoted message said:

I have a fairly old (8 years or so) specialized Allez with a Shimano 105 drivetrain which I now
use exclusively on my trainer. The drivetrain has about 10,000 miles of use on it. Lately I have
been getting a squeal (high pitched screech) when I use the bike on the trainer, particularly when
I am using certain cogs. Any views on how to fix the problem? Replace cogs (entire freewheel at
this point I guess)? Do I need to also replace the chain and the chainrings? Or could the squeal
be coming from the rear hub? It's hard to isolate the sound?

Are you sure it's not the trainer squealing? Or the tire slipping on the trainer's drum? Maybe the
rear hub? I can't see how worn cogs would cause a squeal.

If you have 10,000 miles on the chain it probably is "stretched." Measure 12 full links, and replace
the chain if the measurement is more than 12-1/16". Then, if you get skipping, replace the cassette.

Art Harris