Iím having a really annoying problem with the bike set up at the moment. Shifting up through the rear cassette is not as it should be, it sticks in gear or jumps two at a time. Shifting down through the gears is OK. Happens regardless of the chain ring.
Itís under warranty but I like to be able to fix things myself and it might not be more than wear and tear. Past experiences have not been great with the lbs they tried to replace the BB when all they needed to do was grease the pedals/crank that they had just fitted!
Do you think its an adjustment thing, bent hanger worn parts?
And sorry - I know shifting has been done to death but I canít find anything that matches this.
Trek SU600 new in September last year
It does about 100 road miles a week and has probably clocked up about 1500+ miles since new.
That model has an SRAM 9 speed cassette with an XT derailleur. Shimano chain but I swapped early on to an SRAM hollow pin.
Bike is cleaned weekly and re-lubed with finish line Teflon dry lubeÖ
Bike in the stand starting with smallest cog and largest ring
Will shift progressively 9-1 through the cassette without missing. (obviously thatís not a usual sequence but the same happens if shifting 9-4)
First up shift and the derailleur will visibly moved but not change gear. Usually get a bit of chatter.
Second up shift will now move up one gear.
Third up shift will move up one gear. And so on
Shift from 7 to 8 will jump straight to 9th gear.
Shift back down is OK.
On the Road, itís bugging me big time, I like to work up through the gear but I keep having to shift up two down one in order to select the desired gear. With hindsight this might have been getting worse since it was new Ė not sure. Occasionally it would seem that a change up was almost non existent, I just put it down to my supper smooth technique. ahem
Tried So Far:
Cleaned and lubed
Checked derailleur for sticking and free running movement Ėno problems
Checked cable for binding Ė no problems
Derailleur spring looks OK. But thatís just a visual check
Changed chain in November to hollow pin Sram
Tweaked the micro adjusters
Tweaked micro adjusters Ė worked through the range ľ turn at a time.
Changed back to original chain (only few hundred miles old) Ė no change
The cassette looks OK / teeth donít looked hooked and the problem happens across the range even on gears that are lightly used.
The bikeís never been dropped or crashed and everything looks straight. But thatís eyeball only.