gear ratio

[jonesie8807]

i have a doodle bug with 6.5 hp blue engine. it has 12T on clutch and i think 72T on wheel. it accelerates really quick and tops out at somewhere little under 30mph. i was wondering if i dropped the wheel sprocket to a 60T would i get a good speed increase and would i still have enough low end torque to conquer some hills without burning up the clutch?

 

[ironman]

your gain would be about 4 mph. by the speed calculator i guessing your wheel hight is about 16 inch total.

 

[jonesie8807]

thanks they are actually 14.5 and would dropping the sprocket size burn up my clutch if i were to climb a few hills?

 

[oscaryu1]

Maybe 1 or 2 teeth wouldn't hurt. I'd say a 1:4 ratio would be really close. 1:5 is a good all-arounder. 1:6 are for torque heads.

 

[Jerryburger]

The motor has more than enough stink to pull 4:1 on that bike. I think it's 5.5>1 stock. Double check the tooth count. I noticed the recent DoodleBugs have a larger rear sprocket than the older ones like mine have. It might have been due to the Lifan 2.8 having a hard time getting it up to speed.

 

[jonesie8807]

thanks