Gears skipping

[Cyclemonster77]

Hi all,
Need some help, I have a really annoying problem with my road bike.
Under load up hills in second and third gear it skips randomly.
I've replaced the chain,rear mech,cassette,rear hanger,shifter,and put all new cabling.
I set the gears up on the stand and they are perfect,
Any advice would be great.

 

[steve50]

Welcome.
Firstly have you used the correct chain for your cassette?
Do you have any excessive wear in your front chain wheels?
Is your rear mech set up correctly?
i found that with one of my bikes, the solution was to tweak the cable adjuster whilst out on the road, it can be difficult to simulate a hill climb on the stand so therefore you cannot place the chain and gears under the same stress and tension. I would turn the cable tensioner at the rear mech just a quarter of a turn at a time then pedal a few metres to see if it still jumps.

 

[MattDB]

Yes I find its never the same in the stand. When you say skipping randomly - ie it moves to the next previous gear? (Traffic lights were made purely to give cyclists time for tweaking cable tension).

 

[screenman]

Rear mech alignment?

 

[Cyclemonster77]

Hi Matt
Nah it doesn't jump to the next gear,
like you say I could deal with that with the barrel adjuster.

 

[Cyclemonster77]

Rear mech alignment?

Hi yeah I've put a new hanger on and used a alignment tool

 

[Cyclemonster77]

Welcome.
Firstly have you used the correct chain for your cassette?
Do you have any excessive wear in your front chain wheels?
Is your rear mech set up correctly?
i found that with one of my bikes, the solution was to tweak the cable adjuster whilst out on the road, it can be difficult to simulate a hill climb on the stand so therefore you cannot place the chain and gears under the same stress and tension. I would turn the cable tensioner at the rear mech just a quarter of a turn at a time then pedal a few metres to see if it still jumps.

Hi Steve,
Its got all 105 set up and replaced the hanger and used a alignment tool.
I haven't checked the front chainset though as I thought it was all happening at the rear.

 

[Globalti]

If you changed the cassette and chain but not the chainrings that's your answer. A mismatching new chain will jump around worn rings surprisingly easily under tension.

 

[DWiggy]

Did you change inner and outer cables?