I have an lt80 with a ported 105, shaved head, ct pipe and a 20 mm carb with a k&n filter. It runs on race gas. At the drags it wants to starve for fuel on the top end. It has a blaster petcock so I know that's not it. It had a 122 main jet and I just moved up to a 135. It loads up a little after a long idle but runs way better on the top end but it still starves when it's screaming. I have yet to see a faster 80 but I would like to get that last little bit out of it. The plug looks perfectly coco brown. Any tips for me?

 

Welcome to the forums.
What's the compression on your 96cc motor?

 

I'm really not sure. The guy who built the motor built my banshee, blaster and they are very hard runners. I should just take it back to him but I'm just trying to save some bucks. This is the 3rd lt80 I've had, I had a ct kit in one, then I had this guy build me an 80cc that just smoked the ct bike and now I just bought this one from a buddy. My 80cc bike was a little faster when they raced but this one has a little more pull in the long hills. It just starves a little when its screaming. Everything else is great.

 

I never had to go past 125 main on the 20mm.

 

I feel like the bowl is being sucked dry in the long screeming runs. The only spot that the fuel would be slow is in the float valve. Have you ever heard of maybe drilling that out a little or is there trick I can try to fix it.

 

Maybe try a stock carb. I can rev a stock carb to the moon w/o starving (13500+rpm).
I'd still like to know the compression. (I'm a curious fellow) LOL