Old 2 stroke with small shaft

#1
Hey people so basically I have a tiny little 2 stroke Fox Motori Engine and it has a 12mm keyed shaft I was wondering if I would be able to put a normal centrifugal clutch on it as I have seen people put a centrifugal clutch on the little Ohlsson And Rice engines so is it possible to put a centrifugal clutch onto my engine?
 
#2
Sure, you could sleeve your shaft up to a normal size. You could have a clutch custom made (probably not the cheapest option.)

Or you could put a sprocket on the engine driving a jackshaft and install the clutch on the jackshaft. That might be the best especially if the engine is higher revving and you want it to get up into the powerband before the clutch engages. :thumbsup:
 
#4
My engine is very small only 1.6HP and 39cc I believe I realize this is a very low HP for a bike but I really want to make this work what kind of work would a sleeve take,thats the one that sounds like what im looking for.Would it have to be shop made or would I be able to make it myself.
 
#5
That engine runs well above the normal RPM range of the 4-cycle stuff. 6-7000 revs, and power will be limited at the 2000 or so a minibike clutch will engage at. A 2:1 or more reduction to a jackshaft clutch makes much more sense. You'll need nearly 10:1 overall to get it to pull decently, and a clutch engaging just above idle won't be good.

Still, sounds a swell project.

sprocket-250.jpg
 
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#8
So run a sprocket straight from the engine shaft leading to a jackshaft with a larger sprocket and on the other end a centrifugal clutch?
 
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