Suggestions on annoying indexing issue

[retroJIM]

Hey folks, I need a bit of help with the indexing on one of my bikes.

The groupset is a 7 speed Deore LX from the early 90s but the Cassette (an HG-200) and chain (a 7 speed KMC) are new. Basically The highest gears are OK and the lowest gears are ok but it tends to jump around and clatter in the middle.

I've got a derailleur hanger alignment tool and the hanger was a bit bent, it's now straight and things have improved but its still not right. No amount of cable tension adjustment seems to improve matters either.

The cables and outers are used but in pretty good condition.

I'm hoping to pop back out for another look this evening so in the meantime does anyone have any suggestions for me to try?

 

[d8mok]

Is the mech itself straight?

 

[retroJIM]

Is the mech itself straight?

It looks straight but hard to tell. Annoyingly I don't have a spare to swap out.

 

[CassidyAce]

If the mech itself is straight, I would start looking at the jockey wheels. Are they worn or wobbly?

 

[retroJIM]

I've taken the mech to bits and given it a clean. There's a little bit of play in the jockey wheels but it doesn't seem too bad.

 

[grey-beard]

Probably not, but, last time I had an issue, it was a stiff chain link. Worth a mention.

 

[d8mok]

It looks straight but hard to tell. Annoyingly I don't have a spare to swap out.

If you decide you need a mech I’ve got a few M567 ones which are £10 inc postage.

My usual train of checking is gear cable , mech hanger , worn chain , worn cassette , bent mech. It seems you’ve eliminated most of those.

I assume using Shimano shifters?

 

[Freddyman90]

Probably not, but, last time I had an issue, it was a stiff chain link. Worth a mention.

I’ve had the same issue. Bike hadn’t been riden in years and despite being like new the links had stiffened in the shape of the jockey wheels. Loads of wd and patience and they freed up

 

[jonnyboy666]

screams hanger is still a bit out to me, so check that first, second thing is the mech might be bent, stand to reason that it may have been bent if the hanger was bent, third thing would be to replace the cables (inner and outer). if that doesn't sort it then is the shifter worn, the ratchets on the older stuff can get vague

 

[retroJIM]

Thanks for all the suggestions

I've ordered some new cables so I'll double check the mech hanger when I fit those. If it's still not right I'll swap out the mech. @d8mok I might take you up on your offer.