As you've now discovered the pipe moves the power curve up in rpms over stock...In addition to playing with the variator wieghts you can try different springs on the rear clutch...You can add stiffer springs to have a higher rpm when the clutch engages or put a stiffer spring in the clutch itself which will keep it in low gear longer...Most pipes come with a clutching kit containing these spring kits..I got a set from Hetrick's..Maybe Lt80 sells them as well?...Take a look at your spark plug and make sure it is not too lean (whiteish or very light colour)..

 

Thanks,I went up on the main jet to a 90 and it performs alot better.I like it,actually sounds like a 125cc dirt bike,my little girl is afraid of the new sound and throttle response,I got her to ride it some today,a bit skiddish,maybe she will get use to in time,amazing what mods will do to a stocker

 

Oldyeller is right, alot of low end take off is in the rear clutch. I just installed all the springs in the rear up 500 rpms. You just have to make sure that the rollers you have in the variator aren't too heavy, in other words you don't want you variator coming in before your rear. I am not saying that everything isn't important, but this I just did for the race yesterday and worked well, and I am running 6 grams wieghts with out a pipe.