XT shifter trigger – sometimes not working

Have a set of XT 770 9spd shifters with 2 way release on the upper lever. Last couple of rides the upper lever trigger has been ‘failing’ about 50% of the time when pulling the trigger. Still works great when pushing it but just wondering whether it’s worth opening it up and taking a look.

Any clues or tips on what’s next?

Had a shifter get a small bit of grit in somehow and did the same.

I usually drown them in my choice of spray,then airline it out while operating the triggers.

Often caused by the grease on a little pawl gumming up, and causing it to stick on the shaft it’s supposed to rotate on. A dribble of GT85, and a little working back and forth, usually gets it working again. Unfortunately, you need to remove the shifter from it’s housing to do this properly as you need access to wiggle the pawl, and randomly soaking everything in GT85 will break down it’s lubricating grease.

check cable for uneven operation / wear / kinks too?

but yes, probably drown it in lube would be first stop.

and randomly soaking everything in GT85 will break down it’s lubricating grease.

Yup,that’s usually my plan.
I always think of excess grease as a big dirt magnet,thin film of lube FTW *

*but that’s probably just me 🙂