doesnt know what to do

when i go to pull away on the swing she dosent pick up all that well a sort of stutter i suposse im only talking of half a second then she responds as she should new air cleaner spark plugs fairly new its just annoying rather than dangerous .this happens i think with the front brake held in and launching at 3000 and also oppening just of idle.engines ideling smoothly.cheers for any advice

All we can do is speculate as to what the problem might be. So here it goes…Idle set to low, need to add a fuel injector cleaner to fuel tank, Variator ramps need cleaning, new variator rollers needed, needed a tank of new fresh fuel, and last but not least…take a look at your clutch springs.

OR...It might be the dreaded fuel presure regulator starting to go bad.

OK…I’ve speculated enough. Someone take over!!

P.S. Your idle speed should be set at 1,300 +/- 100 min (rpm) when engine is warm.
https://www.silverwing600.com/t1140-idle-adjustment-please-read-2-9-10

thanks for the quick reply i use redx which is a fuel injection cleaner over here in the uk.ive just replaced the rollers with brand new dr pulley 26g .i did notice that when i changed the rollers that there were like slight ridges on the ramps sort of half way up and one near the top dont know if this could effect the running.Idle set at 1400