Ok this might be an obvious question!

[DJ]

My oldish raleigh MTB , thanks to invaluable advice on here I reset the indexing, it's working much better now.

Except for moving down on to the smaller gears from the larger ones.

It does eventualy drop down but only after I've done quite a few revolutions with the pedals!

Do I simply need to replace the spring that pulls it out or is there more to it than that?

Any advice greatly recieved.

 

[Steve Austin]

Is the dérailleur moving slowly or is it the chain taking time to move over?

If its the dérailleur moving slowly. its normally one of two things
1. gunge in the rear loop of cable just before it goes into the rear mech
2. gungy dérailleur pivot points

1 is fixed by replacing the rear loop of cable, or oiling the cable a bit. but ime if its sticking it won't be long before it needs changing for a new bit anway.
2 is fixed by oiling the dérailleur pivots

check park if you get stuck
http://www.parktool.com/repair/readhowto.asp?id=64

happy fettling

 

[DJ]

Thanks for pointing me in that direction!

I need to do a bit more cleaning and sevicing, that's good it sound's cheap to fix.