ts1 cruising problem

[Hopey]

i am running a mild tune TS1 with a nk road tour pipe and filtered 35 mikuni. the scooter runs smoothly through gears and is really quick, the problem i have is when cruising it burbles and then runs smooth then burbles,it doesnt seem to want to flatten out and run smooth. it does this when i back off the throttle to about 1/4 even at speeds of 60/65 mph. is this common with these pipes? or is it a jetting fault, i am currently running a 25 pilot, under load its fine and pulls smoothly. hope someone can help

[wack 63]

I had the same problem with same pipe and carb. I couldn't get on with a 25 idle so run smaller but the main problem was a worn needle,even though it didn't look worn but measurement said otherwise. I fitted a new one and it cured the stutter. Most TS1's seem to have an area where there's a rough spot when not on the pipe, ie they don't like pottering around at a constant rev/ speed. I think it's just the nature of the tune.

[Hopey]

Cheers I'll change the needle and drop to a 22.5 pilot and see what it's like