Levo Gen 2 Turbo Levo - Lower gears jumping on steep hills

[Grannyjones]

The lower gears have started jumping on steep hills. It is an 11 SRAM NX Speed Cassette.
When the bike is in the stand all the gears shift correctly but it starts playing up when going up something steep. It is only when there is a lot of torque going through it and in the bottom gears. This same chain and cassette have been on for ages and are at about 0.75% wear. The cassette has been through a few chains though but this chain and cassette combination has been on for a while with no issues until recently.
Any ideas what it could be ?
Could it be a bent hanger or rear mech ?

 

[MNTurboLevo]

The lower gears have started jumping on steep hills. It is an 11 SRAM NX Speed Cassette.
When the bike is in the stand all the gears shift correctly but it starts playing up when going up something steep. It is only when there is a lot of torque going through it and in the bottom gears. This same chain and cassette have been on for ages and are at about 0.75% wear. The cassette has been through a few chains though but this chain and cassette combination has been on for a while with no issues until recently.
Any ideas what it could be ?
Could it be a bent hanger or rear mech ?

How many miles on your cassette, chainring and chain. If it only skips while under load this is where I would start.

 

[Grannyjones]

Actually I've just checked - The chain is now at 1% wear on the Chain Checker not 0.75% anymore. Would this be the reason ? Just worn out ?

 

[Grannyjones]

How many miles on your cassette, chainring and chain. If it only skips while under load this is where I would start.

I've not recorded the mileage but it would be quite a lot

 

[salko]

Bent derailleur is not the reason for chain skipping on a cog ... Wear is. Time to replace the cassette, chain and chainring.