Skips a ratio - regardless of how finely tuned

[ibbz]

Chain keeps shifting 2 ratios up On same 2 cogs With one change regardless Of how finely tuned
It’s 8 speed cassette with LX mech - using 8 speed KMC chain.
Would a 9 speed Chain help as the 2 ratios - 1 of which is skipped are quite close in teeth and size - as now it seems I have 7 gears rather than 8.

 

[greencat]

Chainline? Sticky inner/outer cable?

 

[ibbz]

Chainline? Sticky inner/outer cable?

Never thought Of chainline - I’ll check

 

[marc two tone]

Re:

If it's the same 2 cogs, surely it's a shifter issue. Over pulling that particular pawl, thingy. Chain issue would be all over the different configs.

Are the shifters rapid fire?

 

[d8mok]

Re:

Bent hanger?

 

[SamOsborne]

Re:

Once Had a similar issue before realising I was using a 9 speed shifter on a road bike setup with an 8 speed cassette and a ratio that was never going to index correctly.

Bent derailleur or hanger symptoms are similar although it could be as simple as a worn ferrule on the outers.

You’ll find the answer and kick yourself no doubt

 

[tintin40]

I'm having similar issues. And agree it looks to be a bent hanger. I'm in two minds fix myself and buy the correct tool or find a local shop I can trust to fix?

 

[ishaw]

Re:

Had the same issue/symptoms. New cassette, chain, crank and as new shifters and mech. Worked fine with previous 9sp used setup, but with 10 I just couldn't get it to index properly across all gears. Mech hanger was slightly out which didn't impact 9sp, but with the closer 10sp it did. I ordered a new mech hanger but while waiting pit an old rear mech in and used that yo realign it and all was well again. Didn't use the new hanger in the end.

You can also use a threaded rear axle as an alignment tool. No need for expensive tools for this job really, aside from your eyes and a gentle hand.

 

[ibbz]

Re: Re:

If it's the same 2 cogs, surely it's a shifter issue. Over pulling that particular pawl, thingy. Chain issue would be all over the different configs.

Are the shifters rapid fire?

Yes it’s an Deore LX set up -
The hanger isn’t bent from what i can see - it’s an 8 speed cassette - I’m wondering whether the shifters are 8 or 9 or whether the mech is - it’s my M-Trax which I’ve given to a good friend to ride and keep for as long as he wants - can anyone recognise this rear mech ? It may be that it’s a 9 speed on an 8 speed cassette - which may be the issue here. LX shifters but can’t remember which ones

 

[ibbz]

It’s M570! Mega 9.
I think the shifters may be the same

I think the problem may be solved