denaffen

I've got a Tourney front derailleur (top swing/triple version) and when you press in on the trigger shifter, the shifter doesn't return to the "out" position. You have to pull it back out. I've already replaced the shifter itself with no difference. What should I be checking? Is the spring in the derailleur shot? What am I missing?

cxwrench

Undo the cable from the derailleur and see if it moves smoothly. Also check the cable, is there a bunch of drag when you press the 'downshift' paddle on the shifter? This is pretty simple stuff. There are 3 parts to the system:
The shifter
Cable/housing
The derailleur
Separate them and you'll find the problem.

oldbobcat

My general guide for derailleur trouble shooting goes like this. First disconnect the cable. Test the spring by pushing on the derailleur with your hand. If it pushes back, it's not the spring. Second pull on the cable with your hand, while you actuate the shifter with your other hand. If you can feel the shifter pull and release cable, it's not the shifter. Third, feel for friction in the cable. If it's rough or sticky, replace cable and housing.

My hunch is it's a sticky shifter. This things are cheap and the gunk up easily. To ungunk, spray aerosol solvent into the shifter. See if that frees it. If it does, spray an aerosol lubrincant in there, like Tri-flow. Wipe up mess.

sovende

For sure, check out the three basic components of the system but my guess would be that the mechanism within the bar mounted shifter is “gummed” up and failing to properly engage and/or release the ratchet. I’d spray some solvent into the shifter mechanism while attempting to upshift or downshift. Having a repair stand or someway to allow for turning the crank arm with the rear wheel off the ground makes this a lot easier!