Right Hand STI Shifting Problems

jacksomd

Hi,

I have a bike (now my winter bike) which has a 9-speed Shimano 105 groupset. The bike and groupset are about eight years old.

Recently, I have been having problems with the the right-hand STI lever - the one that controls the rear deraileur. Sometimes, when I shift up the cogs (from small to large) the lever, when pushed, moves in but I feel no resistance and no shifting happens. I will some times have to push the lever all the way in (with this no resistance) once so that I can get the bike to shift. The lever just moves in and feels really loose. I then get about three shifts (either all at once or one at a time) before the problem happens again. There seem to be no problems using the small level to shift down the cogs to the smaller sprockets.

Anyone have any idea of what the problem could be? Could it be a problem with the STI lever itsellf (eg broken?) or do I need to adjust the cables in some way?

I'm not too solid on gear adjustments so any pointers as to what the problem might be or where I should be looking would be greatly appreciated.

Thanks,

Marcus

Bugly

Sounds to me that it is time to buy a new lever they do wear out and the parts are not servicible.

ash68

might be worth checking the inner cable is running freely, lubricate it at the guide under the bottom bracket and at the rear mech. make sure there is no kinks or damage to the outer cable. I would change the inner and outer cables before condemming the sti levers, might cost afew quid,but cheaper than new sti's. As the original poster suggests, make sure the cable adjustment is spot on, and the rear mech is in good condition..

Monty Dog

'Sticky cables' is more symptomatic of your rear mech failing to drop to a smaller sprocket, whereas your problem appears to be on the upshift i.e. the ratchet in the lever not engaging and therefore pulling the cable. Try blasting the innards of the STI with WD40 or GT85 to clean out any gunk - also make sure that the nipple on the cable is seated properly and that there is no fraying. Similarly, check that the lever hood or tape isn't fouling the innards. Trouble is the innards of STI rely on some stupidly small springs and once they've gone, it's hard to get them going again and sadly there's nothing user serviceable. Worth checking ebay - single levers often come up - particularly the undamaged lever from a crash.

alan_sherman

Check the inner cable isn't fraying near the nipple - this happened to mine recently just before the cable snapped at this point.

stevec205gti

My similar age TIagra right shifter does the same thing - but only when it's cold. It's only been a problem the past few mornings