mY G/F has recently bought a Spesh Myka FSR and loves it, unfortunately she is having real problems with the left-hand Shimano Deore rapid-fire trigger shifter (front mech).
It is causing her real pain, so much so she can’t shift rings halfway through a short ride & her thumb knuckle & wrist are sore for several days afterwards.

We thought about twistgrip but she tried my commuter bike & hated the shifting action.

I’ve had a fettle & moved shifters/brakes around but although my fettling helped a little it’s still causing her pain.

Anyone other female riders had this problem & what to do about it?

It’s only the left-hand that’s a problem – right hand is fine.

Friends have gone down the Sram route as the shifting is lighter, I’ve got an X-0 rear mech on eBay just now, if you win it I’ll send you the shifters for free.

My wife’s Vita had really hard shifting from new, but it is definitely loosening up after a few weeks of use.

Similarly to your experience, I moved the pod inward on the bars and adjusted the angle which did make a little difference. I think the springs on the mech soften up a bit with use, Mrs Bassspine reports that it’s much better recently.

The High stop screw on the front mech may be wound in too far, so pushing into specifically the big ring, stopping the front mech from moving properly.
Could also be something else stopping the front mech from moving through its full range

Check theres not somethign blocking the shifter internally.
The inner cable head may not fully be in its slot (release to the inner ring, and open the philips screwdriver cap) and as you try to drag it round it could be catching on the casing of the shifter

It could also be that the cables are bunged up with something

I reckon its likely to the high stop screw on the front mech isn’t wound out enough though, so check that first

I have no problem with the shifter in question, it’s well set-up & I find it pulls very lightly & smoothly.
It’s just she’s having problems with her thumb & we think it’s the action of shifting thats hurting her.

May need to move the pod inwards & upwards again to see how it feels.

do you have trouble shifting if you ride it?

you could convert it to a 1 x 9 for her

I find XTR is about as soft shifting as you can get…
Or try a twist shifter for her?

powerball and a dose of mtfu

or teach her rocketdogs wrist strengthening exercise

My wife had the same problem, used to end up shifting with her Palm when changing into the big ring, it’s little hands that cause the problem. A gripshift may be better.

I’ve had thumb problems with the LH shifter in the past. Things I tried to make it easier

make the shifting silky smooth with fresh, lubed cables & outers.

move the shifter towards the grip so my thumb was less extended, I also tried moving it towards the stem, but that didn’t help

twist the shifter around the bar closer to me so my thumb got most power in the hardest part of the push

changing gear whilst pedalling comfortably rather than when the chain was under big tension

Unless she has other joint problems, it sounds like an ergonomic problem, so it’s probably worth really twiddling with the positions of the gear.

You could try NSAIDS to reduce the pain afterwards.