which cylinder? i was messing around with a 1 hp yesterday at the shop. it had a 14mm intake derestricted, 52 jet in a 14mm carb, original stock airbox and 13 x 45. bike ripped up to 22 mph but wouldnt go faster. i really dig 16 x 45 with a stock setup for decent low end but still going mid 30s to get you down the road. also tune your clutch.