I am running a xt crankset I have replaced the outer ring with a bash guard and am using 24×34 front rings on the middle and inners. I fitted a 2×10 slx shifter and fr mech.
It all operates ok to a point but the shifts can be a bit inconsistent and also clunky.
Should I have stuck with the original 3×10 shifter and mech and just wound the stop screw in ?

Unless you changed the spacing on the front rings to reflect 2x chain line then yes you should of just used the 3x wound in.

I would have thought a 2 x 10 FD would be a better shape, as it’s not trying to accommodate 3 different ring sizes in its cage design.

It sometimes helps to get the right spec for a 2 x 10 FD. Yours might be anything up to a 42 x 28 model which might not work as well with your rings as a triple FD, as your rings are effectively a normal middle and granny.

Thanks for your help guys think I will try going back to the triple mech for now and save up for a dedicated 2×10 crankset ,probably an SLX.

The FD you have should be ideal for your 34 ring. Did you change the shifter to a double as well, or are you still using a triple? If a triple, you need to experiment between using granny to middle, or middle to big as the shifting sequence. I run an XT triple 9 speed with a 22t, and 36t and bash. The FD is an SLX double, and I found, perhaps not unsurprisingly, that the best setting is granny to middle. However, to do that you need to set the mech up properly to start with, getting the cage of the mech as close to the lip of the bash as possible, then making sure the cage lines up exactly fore and aft. Jam a 6mm hex key in the mech to hold it open against the spring so you can see it’s properly lined up before you add the cable. Now, chain on, and use the lower limit screw to wind the cage so that it has about 1mm clearance from the inside of the inner edge of the cage when the chain is on biggest rear cog. Fire off the shifter so that it’s at lowest setting, fit the cable with no slack but no tension either and set the chain on the smallest cog. Now, shift up to the big ring, by hand if you have to, and now use the upper limit screw to adjust the mech so that there is a bout a mm of clearance between the inside of the outer edge of the cage and the chain. At this stage it should work fine. If not, add or remove cable tension on a trial basis. A lot of the shifting problems you have may well be cross-chaining. I managed to break a chain in big/big with this setup.

If you can’t get this combination to work, cable the mech so that you use the middle setting on the shifter on the granny, and the upper setting for the big ring.

24-34 is a more common 2×10 setup. A 34 chaniring is rather uncommon IME; do the ramps and pins align properly with the shift points on the 24? If they’re different brands, they may not.

Both of my main bikes are set up 2×10 w/bash on a triple crank; 24-36 and 26-38. Both use the 2×10 front derailleur and shifting is great.

^ I meant to say 24-36 is a more common 2×10 setup. A 34 chaniring is rather uncommon IME; do the ramps and pins align properly with the shift points on the 24? If they’re different brands, they may not.

Both of my main bikes are set up 2×10 w/bash on a triple crank; 24-36 and 26-38. Both use the 2×10 front derailleur and shifting is great.