36 or 39 for my bike.

GoldenMotor.com

Moto

Member
Jan 7, 2012
403
15
18
San Francisco, CA.
Hi everybody, after upgrading my bike a bunch I think that the next thing to be done is to upgrade the sprocket. I am wondering weather to go with a 36 or a 39 tooth sprocket. Here is my setup:
66cc engine
puch 70cc hi compression head (1 head gasket)
Highly port matched intake and exhaust flanges
15.15 dellorto carb
hacked up expansion chamber exhaust from moped
Pic as she sits: (minus the new exhaust)



Speed:
Right now she pulls up to a top speed of around 28-29 on flat FAST and then runs out of gear. When I say FAST I mean you feel like your going to fly off the back while accelerating and it really lurches forward while starting. It has a sh!t load of compression and torque cause of the pipe.
What I want:
I like fast take offs, and I get that gearing down hinders that, but I would still like to get up to speed relatively quickly. I would love to have a top speed in the low to mid 30s.
Soooo... The big question. Do you think a 36 or a 39 (or 40 even) tooth sprocket is better for me? Thanks for the input! Moto
 

borntofli

Member
Jul 27, 2012
306
0
16
tx
I have a 39 on my stock bike W pipe and I can go low 40's....2 or 3 peddles to take off and cruise low rpm 22-25...