Re: Interesting Find
Made by Tanaka of Japan. Tanaka still makes small engines, but not that one. It was marketed in the USA as Bikebug, Sears Free Spirit,Taz Spitz & maybe one other name I can't think of. It put out around 23CC. These were very popular in the 60's and early 70's.
Some parts are still available from Tanaka USA and others need to be either fabricated or taken from a donor engine. I have some parts and engines, still have two that were running when I last used them a couple of years ago. Mike Snyder is a forum member and has a lot of expertise with these engines. These don't have a lot of power, but are smooth running and pretty quiet. On a lightweight bike like that 3 speed it would be nice especially if you don't have a lot of hills to climb unless you don't mind pedal assist. The really nice thing about those engines is that when you disengage the drive wheel from the front wheel of the bicycle and the engine is shut off it is silent running so that you can truly ride the bike as normal. Nice find. There are fewer of these around anymore and at some point will have collector value. It would be nice to leave it on the 3 speed if it is in good enough shape. Sort of a time machine from a few decades ago.
Someday when I grow up I will probably lose interest in toys with wheels, but until then...