Honda GXH50 Engine For A Mini Bike

[omahgarsh]

Has anyone tried this ??? You can get them with a 5/8" keyed shaft so a regular mini bike clutch and#35 chain can be used. Here in Oregon there is a law that you can run a scooter in the bike lanes if it has a 35cc or smaller engine. The wording of the law would fit a mini bike. You can then do a little fibbing about actual engine size. Could be a way to have a simple street legal mini. Probably wouldn't be that fast but it still would be fun and a lot more comfortable than a stand up scooter.

 

[Sunnyknoll]

Hi omah:
I'm currently working on a mini with a Honda GXH50. This bike is from scratch and is roughly half way between a "full-size" mini and a Tom Thumb.....kind of a unique design (if I may say so myself). BTW, this engine winds close to 8000 RPM so it must be "tamed". The way I'm doing this is through the use of a Grube G4 transmission with the 4:1 ratio pulley option. This transmission is generally used on powered bicycles and comes with the clutch. That ratio winds-up turning a 10 tooth #415 chain sprocket. From there I'm running a 24 tooth on a 4" rear wheel with a Kenda 9x3.50-4 tire. Looks like a net of about 25 MPH in the end. Time will tell, but I think this may turn out pretty feasible.

Keep in mind that with this motor, you've got to remove the governor and make a small throttle control plate with return spring. That said, so far I haven't found that to be a problem. I did get quite a bit of information by going to the Motorized Bicycle and Goped Nation websites some time ago. Problem now is that the Goped Nation site has apparently been discontinued. Do a search on those bicycles and gopeds and you'll be surprised at how much info you can get on this engine. Good luck.

All the best, Henry