90 Set up Advice

[mkeane]

I have a 06 90 with PVL ported cylinder 24mm Keihn carb. I am looking for some advice on roller weight, gearing, jetting, spring, etc. This is for my daughter who weighs about 65lbs. and will be racing mx tracks. Thanks for any help.

[ecmini1]

Not sure on your jetting in the north but a 120-125 main with needle on 2nd clip from top should be close. Run a 5g-5.5q roller with 2,000 shift spring and clutch springs depends on brand on the shift spring some are stiffer than others. This should get you near what your looking for. Your porting and pipe combo might be able to run a 4.5g roller just depends where the power comes in.
What rear clutch you running? Belt size?

Hope this helps a little.

[mkeane]

i beleive it has a malossi evolution clutch and a 737 belt. i will have to check on the belt. thankyou