STI problem

[Jon H]

My righthand 105 STI lever seems to have suddenly developed a strange fault, and I can't figure out what's wrong.
When I move the inner lever inwards to change to a smaller sprocket it tends to stick and not return to its normal position. I then have to push it back, and then the chain moves to the sprocket I want. This doesn't happen all the time, just intermittently.
Anyone got any ideas as to what could be wrong?

[Rob]

too much use...

clean it very well, try take as much apart as possible to clean it before your at the stage where losse springs start flying, apply some oils, free up all the movement by wiggling it all about whilst oiling...dry of excess oil, give it a go..

if this fails, butlers have got a shimano expert out the back.


then if still all fails

http://www.ebay.co.uk

[BrendanM]

You could try flushing out the STI mechanism with WD40 (I would use GT85 as it also contains a lubricant) before you take it apart.
Put one of those thin tubes on the spray nozzle.
Friction in the gear cable and rear mech or issues with the indexing adjustment might affect the lever movement.