Rubbing on disc wheel

Triathlon Forum
1

Hello

I recently decided to buy a SES aero disc wheel on my TT bike through my LBS. My bike is a 2021 cervelo P5 with disc brake and sram Force drive train, running a 10-33 cassette with 50/37 in front. After final adjustment, the chain is rubbing the disc wheel when on the easiest gear. LBS told be it’s the best they could do and that is normal for a disc wheel as the easiest gear is not used very often so I should not worry about this. I don’t think that was meant to happen by design.

I didn’t get to see the bike yet but from what I understand the rub is at the derailleur arm as he told me he removed one link on the chain to help straighten the derailleur arm to lessen the rub. He also told me when on the stand it doesn’t rub and only rub when putting some torque (standing) on the pedal, so I figured it was a flexing under load issue.

Did you ever see similar issue?

What can we do to solve this?

2

Check that:

  1. The aluminium derailleur drop is true/straight. It might be bend

  2. That the chain is the RIGHT length

  3. That the disc wheel is true, i.e. 100% centered between the chain stays.

3

That isn’t normal.

4

Hi there,

Yes. I’ve had that very same problem. My bike setup is CUBE Aerium c:68 rim brakes with a PRO disc wheel. I’ve managed to minimize it by straighting up the rear derailleur arm with a special tool, and adding an extra spacer between the wheel and the cassette. Also, by putting some vaseline on the edge of the arm where it touches the wheel.

5

Most of the time when I see this it’s a chain length issue. I had to take links out of at least 1/2 the bikes I was working on last time I wrenched at IM Kona.