Please explain transmission types?


New Member
Apr 25, 2020
I am looking at several different 49cc 4-stroke kits for sale on amazon and they have a belt drive a double chain drive and a single chain drive.
I live in Florida and have no hills here and I weigh about 165 and would prefer speed over torque.

There is a video in youtube from bikeberry that says the double chain has a 6.8:1 gear ratio and is better quality but slower than single chain drive and the single chain has a 3:1 gear ratio but is faster than the double chain. I believe the 3:1 would be faster top end speed.
I have no idea about the belt drive though.

How can I get one of these transmissions to go close to 35+ mph constant speed?
Can the double chain go 35+ mph constant?

Which one is better regarding longevity?
Which one is better regarding torque?
Which one is better regarding speed?

Also I have a tecumseh H35 motor in great condition; what transmission will fit on this motor?