transmission options? jackshaft

[holdenrodder]

hi, i need to build a bike to make the 25km trip to work every day, as i am losing my licence and theres no public transport in my rural area....
im still trying to decide on a setup, and i still know very little, but im willing to learn. there is one reasonable hill on the way to work, so i was thinking a four stroke? any way, the main thing i wanted to ask was what transmission options are there other than a jackshaft setup? i was thinking of mounting another sprocket to a three speed hub, on the outer of the hub, and using that as a gearbox between the engine and the wheel? but im betting you guys have some better ideas, or can see the holes in my plan that i am oblivious to
thanks!

[Fabian]

If you have a reasonable hill to climb and need to do so in all weather conditions and want dependable reliability, the best option is a SickBikeParts shift kit, which has been designed to work with 2-stroke and 4-stroke engines, depending on which kit you purchase.

Best to grab the delux version as it contains all the necessary tools.

[loquin]

hi, i need to build a bike to make the 25km trip to work every day, as i am losing my licence and theres no public transport in my rural area....
im still trying to decide on a setup, and i still know very little, but im willing to learn. there is one reasonable hill on the way to work, so i was thinking a four stroke? any way, the main thing i wanted to ask was what transmission options are there other than a jackshaft setup? i was thinking of mounting another sprocket to a three speed hub, on the outer of the hub, and using that as a gearbox between the engine and the wheel? but im betting you guys have some better ideas, or can see the holes in my plan that i am oblivious to
thanks!

Check out this approach. It uses a 33cc engine, and a pocket-bike CVT. At low speeds, the CVT is engaged, adding an approximate 2:1 reduction, in addition to the 3:1 gearbox. As the load decreases, the CVT ratio gradually shifts up to a 1:1

If you had a 6:1 sprocket reduction from the CVT to the rear axle, the bike would have a top end about 33 mph, and on hills, would have max torque at about 14 MPH.

[holdenrodder]

thanks guys, any other options i should consider? im thinking of just gearing it right up with a reasonably torquey engine, and getting upto speed with the pedals. more reliability, cheaper, and i could use the exercise anyway