All the scooter engines I've worked on all had a horizontal thru bolt mounting system where the engine hung off of the bolts, and like Dave said those 50cc engines are dogs! On the scooters they only get to 30MPH if that! like TX said You would be ahead of the game if you sold the scooter parts for cash, and with the extra cash from the sale you can buy a clutch for the Briggs. The added horsepower of the 12hp Briggs will surely make up for the lack of a torque-a-verter.
I don't know what 50CC you've been driving, but i just did a motor swap on a kids China whopper chopper scooter.. The original motor got ran down a dirt road with no air filter or anything... The chloride truck had JUST been down the road, DRENCHING THE ROAD in liquid salt, salt water.. :facepalm: Acid Bath Truck, I call them.. :glare:
SO his engine was toast.. :laugh:
Found the same damn motor in a junkyard on a bike that looks like it killed somebody.. I'd upload pics but I'm not spending 20 bucks on it.. :laugh:
Long story short, this junkyard wrecked pieces missing 50cc Honda Knockoff, bolted into kids thrashed out Honda knockoff moped would do about 50 miles per hour after I got the thing going and dialed in...
4 stroke, 50cc, torque converters..
Goes like a bitch... BY FAR the fastest 50 I have ever been on...
Faster than my Hodaka with H70 Tecumseh big block... :mellow:
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It can be put on a gokart, but it would be a hell of a job.. If it runs sell it and buy something different...