chain slipping on rear cassette with 6870 Di2

richiegwy
richiegwy Posts: 171
edited March 2015 in Workshop
Over the last while I have noticed that my chain has started to slip of the middle couple of sprockets on the rear cassette whether I'm in the small or large front ring. It mainly happens when I try to put power down or running over bumpy road surfaces.
It doesnt happen in the larger or the smallest sprockets just the middle. I have tried adjusting the rear mech setup a little but no change. It happens with different wheels so definitely not a cassette issue.
I have cleaned the chain (but might try it again)
The bike hasnt got a knock or fall so not sure what else to try

Any advice?

Comments

  • trailflow
    trailflow Posts: 1,311
    How much mileage has the chain had ? Do you tend to stay in one particular cog(s) for an extended amount of time ? Could be a bent hanger , or the freehub pawls may be sticking and not engaging with the ratchet teeth. Slim chance of that on 2 different wheels though.
  • richiegwy
    richiegwy Posts: 171
    I'm thinking it may be the chain and have a new one ordered. Its done about 3k and I checked it for stretch with the park tool and it is between 0.5 & 0.75.
    With the Di2 I change gears very often and avoid cross chaining as much as possible. Dont think its the freehub as it happens on 3 different sets of wheels.
    Doubt its the hanger as it only started it since I took the bike out for this year's racing season 3 weeks ago and it hasnt had a knock that I know off.

Categories