The bike is new to me and I have noticed that it felt a little like it was loading up (rich? ) when past half to full throttle. It has a 118 main, 40 pilot , d34 needle with the clip on the second clip from the bottom. The starter jet is a 100. and there is 200 stamped on the needle / seat base. The mixture screw was 2 1/4 turns out. The float arms were a bit higher than parrallel. I am running Motul 800 2t at 25mls per liter ( About 66:1 , having run enduro bikes for the last 10 years I am finding it hard to get to 80:1 just yet.)

Yesterday I adjusted the float arms to be parallel as per the manual. This didnt seem to fix the problem. I was then playing with the mixture screw , I turned it out 3 1/2 as per JSE's instructions but that didnt help either. As a stab in the dark I turned it right in, the idle got faster but it didnt fall off the idle like I had gone past the sweet spot. I then backed the screw out to 1 1/2 turns and it seems a lot better. There is now a smooth pull right through the revs .

I quess the question is , what does this mean.? is the carb jetted to lean? I am assuming that the mixture screw is richening the mixture the further you turn it in? Can anyone point me in the right direction. I dont want to go to lean and burn it up.

Thanks for your help.

The bike is new to me and I have noticed that it felt a little like it was loading up (rich? ) when past half to full throttle. It has a 118 main, 40 pilot , d34 needle with the clip on the second clip from the bottom. The starter jet is a 100. and there is 200 stamped on the needle / seat base. The mixture screw was 2 1/4 turns out. The float arms were a bit higher than parrallel. I am running Motul 800 2t at 25mls per liter ( About 66:1 , having run enduro bikes for the last 10 years I am finding it hard to get to 80:1 just yet.)

Yesterday I adjusted the float arms to be parallel as per the manual. This didnt seem to fix the problem. I was then playing with the mixture screw , I turned it out 3 1/2 as per JSE's instructions but that didnt help either. As a stab in the dark I turned it right in, the idle got faster but it didnt fall off the idle like I had gone past the sweet spot. I then backed the screw out to 1 1/2 turns and it seems a lot better. There is now a smooth pull right through the revs .

I quess the question is , what does this mean.? is the carb jetted to lean? I am assuming that the mixture screw is richening the mixture the further you turn it in? Can anyone point me in the right direction. I dont want to go to lean and burn it up.

Thanks for your help.

I suppose this a Dellorto, so I will chime in a bit. Depending upon your fuel, the #35 #36 range on the pilot may work better, with another turn or so out on the(fuel) screw, which allows more fuel, yet still in range. The 118 main should be ok, but you may need to run the crap out of it to get some heat in the motor and clean things out to rev cleanly. And get that excess oil out of it!