Top end break up drr 70

[jakesdad6]

Here the low down I got a stage 6 pro race cylinder malossi pvl full overange 28 mm pwk round slide carb. I would say from mid to full throttle the bike seam to kinda break up not bad but u can defently here it. The exhaust sound stay the same it's just seam that the motor might be missing and top end. It just doesn't seam to sound crisp any more I didn't do any thing to it it just started happening. So I played with the jets moved the needle and never did it seam to improve. I pretty spot on on the jets I think running a 132 main and a 45 piolet middle clip. I added a new ground I added a little more roller weight thinking that it was over reving. All I can think of is the pvl is messing up I put a zip tie on the coil wire the try n make sure it was a good connection. New spark plug cleaned carb I took apart pvl check the timming clean it up. Any help would be nice thanks

[nitrofish]

Are you doing the testing on the stand? Weather conditions changed recently? I don't think we can ever be spot on with jetting at least here in the ever changing climate of Ohio. Sounds to me your a bit rich on the main. Try dropping the main a bit at a time while running on the stand and see if it improves. Get your airscrew right first, it can effect the whole range as well. Warm quad up, turn airscrew in/out for cleanest idle, not always the fastest idle and proceed to main. Matt.

[nitrofish]

I see you are in Maryland, humidity and dewpoint has to be higher than normal with all the rain you have been getting plus the Hurricane.

[jakesdad6]

All testing is while my son runs the quad. The original jetting was 48 piolet and 120 main I used several other combination with out any real improvements. Seams to me the 132 45 had best plug color just seams to me it's electrical