question about sprockets

Discussion in 'Frame Mounted Engines' started by levsmith, May 13, 2008.

  1. levsmith

    levsmith Member

    Hey i am almost done with my first bike, but i am kindof confused about the sprockets. I am not sure what the RPM is on my motor. it is a 22.8cc ECHO SRM-230 if anyone has some info. (dont worry if you dont think its enough power, cause i only weigh about 140 pounds and i know i'll have to do a little peddling). but anyways, if i am using the gear ratio calculators right, i am trying to get around 25-30 MPH at mid-RPM, so its not screaming. and to get it geared down right, the calculators say i will need 4 sprockets total. with an RPM of 5000, i would need a 12 to 44, then another 12 to 44 just to get it down to about 28 mph with a 26 in wheel. if this is right, can someone tell me an easy way to get another hub with the 2 sprockets welded on it somewhere between the motor and wheel? thanks for any help. oh and i dont have the centrifigul clutch for it, so i'll probably have to get one of the 12 tooth sprockets to be a freewheel and just shut it off at stops, unless someone has a cheap alternative. thanks again.

    Last edited by a moderator: May 14, 2008