You will find that you will need the clutch custom made because the
crankshaft is only 1.250 long (5/8" diameter) with a 14" x 28 fine
thread hole drilled in the end of the crankshaft. The engine top speed
is 7,200rpm and the idle is the 2,700 to 2,800 and you really cannot
mess with it because you will bog the engine down when you try and
accelerate.
We only offer one size pulley and that is 3.20" OD. The "A" belt (4L)
would ride further down in the groove. Do we have a smaller pulley
--NO. Once you get the engine and you start to position it you have to
tell me if the clutch pulley will be inboard mounted (pulley next to
crankcase cover) or outboard mounted Pulley on the end of the shaft by
the bolt and washer.
We can make you up a custom clutch with a shaft extension to fully
support the clutch for $92 plus shipping. The clutch will have a roller
bearing in it so it will not need maintenance. The engagement of the
clutch will be at 2,900rpm so not to bog the engine down.