Mavic cosmic carbone sls

kierhanlon6

Hello I brought some mavic cosmic carbone sls seem good wheels. I went for a test ride gave the bike some really fast power and it sounds like the brake pads on the back are rubbing there spaced away quite a bit so loosened them right off and still makes the noise is that just the wheels?
Thanks
Kieran

ugo.santalucia

kierhanlon6 wrote:

Hello I brought some mavic cosmic carbone sls seem good wheels. I went for a test ride gave the bike some really fast power and it sounds like the brake pads on the back are rubbing there spaced away quite a bit so loosened them right off and still makes the noise is that just the wheels?
Thanks
Kieran

Instead of saying "spaced quite away" and "a bit loosened" can you quantify? Can you get a Vernier and measure how far the pads are? For some 2 mm is "quite far away" for others that's 6 mm

kierhanlon6

7-8 mm mate.

ugo.santalucia

And if you grab the tyre, can you push it laterally so that the rim touches the pads using just two fingers?

kierhanlon6

Yea this happens mate with 2 fingers

ugo.santalucia

You've got 20 spokes and an alloy rim, the carbon fairing is not structural and doesn't give any rigidity, a bit of flex is to be expected. Too much flex might indicate the spokes have no tension... squeeze them, they should feel in tension... (as a metal cable of the same size feels when a lardy boy is hanging from it) if they are, then all is good and normal, if they are not and they feel slack, you have to return the wheels

Bar Shaker

I would also check the seat stays flexing. This is at least as likely. What bike is it?

Bendy seats stays can let the axle location points move, allowing the wheel rim to move across and hit the pads. The stiffer the wheel, the more force applied to the axle points and the worse the problem.

ugo.santalucia

Bar Shaker wrote:

I would also check the seat stays flexing. This is at least as likely. What bike is it?

Bendy seats stays can let the axle location points move, allowing the wheel rim to move across and hit the pads. The stiffer the wheel, the more force applied to the axle points and the worse the problem.

If you can bend a frame with two fingers, then I would say the frame is made of silicone rubber

964cup

Check your QR tension and bearing preload. With the wheel in the frame and QR done up, is there any side-to-side movement at the hub?

drlodge

It might just be the sound of the wheels, my front 50mm carbon tubular wheel make a sound like the brake pads are rubbing, buts its just the acoustics as it goes round.

Try "releasing" the brake either at the caliper (Shimano) or lever (Campag) to widen the brake shoes and give it another try.

kierhanlon6

Thanks for all the advice lads. Will loosen the brakes right off tonight and have a go. They come with the qrm hubs what's best to do with them tighten them up ??
Cheers

kierhanlon6

Thanks for all the advice. My bad it's the acoustic noise of the wheels. I slacked the cables off completely both the front and back. So it's got to be the noise of the wheels. Thanks again
Kieran

Rich-hill

I have the exact same sound. I guess nothing came of this and it was just the wheels then?

kierhanlon6

It's the acoustic of the wheels mate. Nothing to worry about it's just the sound they make. Hope u enjoy them