hi everybody my name is ryan and im new to this site. i just got in to building mini bikes and working with small engines. so far ive built one mini made from scrap pieces of metal, a broken bikes, and a 3 hp briggs flattie i overhauled, it is probably one of the ghettoest minis ever but it is beautiful to me, i hit about thirty on it down the street. my pops doesnt really like me spending my time working on stuff like this he'd rather have me cleaning or something, but once he saw me take off in some thing i made he craked a smile and i knew he was proud of me............... so thats my story...didnt mean to bore you.. now im working on a new mini prodject. its going to be a dragster mini. im building a mildly modified honda gx160 with uni air filter 22mm minuki carb billet rod and flywheel 2 stage header 14cc head .256 lift cam and 18lb valve springs. but the problem is i dont know what kind of clutch and sprocket ratios to use, im going to run a 6in wheel with a 11in tall slick. so i was wondering if anyone could suggest some things.. and mabey post some picks of some mini dragsters.... thank you all very much.......-ryan
15 yearold building dragster minibike and needs help.
Sounds like your engine will be putting out some serious power with those mods and much higher RPM. I'm running a 12 tooth clutch with 60 tooth rear sprocket on my stock and governed 6hp OHV briggs. With more power you can get away with a final drive ratio of 5 without sacrificing too much low end torque. I am topping out at 42 mph at the theoretical max 3600 RPM. So imagine how fast you'll go with the extra RPM you have on that engine. If you'd rather have a bit more torque, then go with the 12 tooth clutch, 72 tooth rear sprocket (drive ratio 6, engine turns 6 times, rear wheel turns once).
