Something very wrong to wear the new slider out in that short time Dan
The only possible reason I can think of is a very slack chain curling up off the sprocket to wear on the slider but, even so, it should have taken that without wearing out so quickly.
Also, the material of the new sliders is harder than the original Yamaha part - or so it seem to me anyways.
Yeah that's what i was thinking :/ the chain has a good 30-40mm slack, is this too much i wonder? i was advised it needs to be 30-50mm on here a while ago. If i was to change to a 14mm sprocket, this would make it worse or better? (as i need new chain and sprockets anyway) Thanks Dan