Shifter tension issues.

[knonist]

After adjusting the front derailleur via the front shifter’s barrel adjuster, now the gears are changing properly and the chain is no longer rubbing onto the derailleur.

However, I’m now having some issues with the tension of the high gear shifter (in the front), I have to press very hard with my thumb to go up one gear (to the larger chainring) and, after the gear was changed, the shifter will not spring back to its original position (it will stay at the far end). I have to pull it back myself.
I have no idea on what happened nor what caused it, and I am trying to avoid visiting my new "LBS" as they will charge me an arm and a leg for it...

(They could quote me £90 on something where another bike shop only quoted £70)

 

[fossyant]

Could be cable snag - just check the cable is running freely.

 

[knonist]

cable seems to be running freely, as it seems to "go down" OK (given the high gear lever is in the "original position").

 

[peanut]

put the chain on the small ring then pull the cable away from the frame and release it. it should snap back quickly and powerfully due to the return spring in the mech.
If it doesn't, check the cable guide under the BB isn't full of crud or the cable hasn't worn a groove in the paintwork and rusted. Thats what happened to mine.

To do a proper job you really should remove the cable lubricate the inner cable or replace it and lube the front mech pivots. Check the cable has smooth curves everywhere.

 

[knonist]

put the chain on the small ring then pull the cable away from the frame and release it. it should snap back quickly and powerfully due to the return spring in the mech.
If it doesn't, check the cable guide under the BB isn't full of crud or the cable hasn't worn a groove in the paintwork and rusted. Thats what happened to mine.

To do a proper job you really should remove the cable lubricate the inner cable or replace it and lube the front mech pivots. Check the cable has smooth curves everywhere.

it seems very wired as the shifter seem to have lost its springiness, pressing the shifter a few time actually hurt my thumb! At one point I though I have to get a new shifter…. I will check the cable again tmr morning,


I guess you had a similar incident then?

 

[peanut]

yep I tried doing it the lazy way first by squirting oil at everything but ended up having to do it properly in the end though . Now it shifts like silk

 

[knonist]

yep I tried doing it the lazy way first by squirting oil at everything but ended up having to do it properly in the end though . Now it shifts like silk

damm....I have no idea how to do it properly...... last time it took me 6hrs to fit a pair of marthon plus.....
I will check the cable first, will WD 40 be good enough or I'll need other lub?

at least it is still working...

 

[HLaB]

I had a similar problem with the rapid fire shifters on my sirrus when it was flat bar like Peanut I tried the quick way at first but didn't get much success untill I took the shifter apart and dit it properly.

WRT WD 40 use it to clean the shifter, it does a quite good job IME but its not an effective lube, recoat with something better.

 

[knonist]

put the chain on the small ring then pull the cable away from the frame and release it. it should snap back quickly and powerfully due to the return spring in the mech.
If it doesn't, check the cable guide under the BB isn't full of crud or the cable hasn't worn a groove in the paintwork and rusted. Thats what happened to mine.

To do a proper job you really should remove the cable lubricate the inner cable or replace it and lube the front mech pivots. Check the cable has smooth curves everywhere.

The cable is OK, I removed the cable housing, it has no rust and able to move freely. One thing I noticed today was: the cable connected to the Shimano Decore shifter & Decore front derailleur has no springiness at all, I was unable to pull the cable away from the frame and the derailleur showed no movement at all; whilst on other people’s bike, I can get small amount of movement and see the derailleur moves from right to left whilst I’m pulling the cable.

Since the nearest bike shop (others will close before I get there after work) is a Trek dealer, I think they will charge me for fitting, a new shifter, a new cable, and a new front derailleur.

 

[Mr Pig]

Maybe the derailier is just stuck. Blast it with some lube and work it free.

 

[knonist]

Maybe the derailier is just stuck. Blast it with some lube and work it free.

But the gear still change though

 

[knonist]

went to the Trek dealer in Cambridge, they didn't even bother to look into it, just asked me to lbook it in for a day or two.

I took the bike away, and went to the station cycle instead, the mechanic spent about 20mins looking at the shifter and the front mech, and found out that the spring in the shifter popped out, fixed it, tuned up my gears, and when I asked to see the bill, and he said, buy them a beer next time.

Got it "fixed", 10mins later, spring popped out again, when back to the shop, the mechanic said I will need to replace the shifter, but the shimano deore doesn't sell the left hand shifter on its own...he suggested me either get it on ebay or buy a pair new which would cost me £60...

It is now "fixed" but need to find a second hand deore shifter in case it fails again.