Gas Powered Bikes

These measurements are given as a general reference.
Due to the characteristics of different frames, frame sizes and shapes they can not be used as an absolute guarantee of frame to motor fit without some modification.

The Drive Chain Sprocket mounts on left side of the rear wheel against the spokes dish side in. The sprocket must fit over the hub in a perpendicular plane with the axle. This insures that your rear chain sprocket spins true with the rear bike wheel. *NOTE: On some older bike axle hubs like on coaster brake models it may be required to slightly enlarge the sprocket center hole to obtain a flush, and concentric fit next to the spokes. This is best done on an engine lathe by a professional machinist. . It is also recommended that the rear wheel be re-spoked to 12 to 14ga.

The engine mounts in the bike frame “Vee” above the pedal wheel sprocket. ( see above pic. )

Consider using Masking or Duct Tape on the front down-tube & seat tube of your bicycle to protect the paint finish while test fitting the engine to your donor bike.

If the distance between the two bars exceeds the engine-mounting span then additional spacers or welded brackets are required. It is suggested that the engine be mounted on the seat tube first and then fitted to the front tube. See figure 1.