As the engine is apart then I'll see if I can easily reverse it.... moving the coil pack round would be simplest. if not I'll use a jackshaft system like you suggested with a 4 stroke or diesel engine. At least it'll be reliable. Some great options thanks. There are so many jackshaft kits in the USA, and the pillow block bearings also give lots of options. Now knowing the names of these items is half the battle!
Just adding a jackshaft won't reverse rotation, it stays the same rotation on left and right sides. Hard to explain in text: A sprocket runs in reverse direction according to being driven from inner or outer side of chain between two other sprockets.
You can run a chain drive from engine sprocket to a driven idler sprocket, with a lot of slack in upper run of chain between sprockets, bottom tight with no slack. Then add two more idler sprockets which consist of a short stub shaft mounted in a bearing with a lock collar on either side of bearing to prevent shaft moving side to side, and a spocket on one end of shaft, these mounted to plates. One plate may be mounted rigid, the other adjustable.
These sprockets have their teeth engaging on inner part of chain loop between drive and driven sprockets in slack area, the same as those two of drive and driven sprockets are engaged. In the slack area of chain and between the two idlers place your jackshaft sprocket resting on upper or outside of upper run of chain, on opposite side that idlers engage, such that the two idlers force chain to wrap up and half way around bottom of jackshaft sprocket to capture it. The adjustable idler sprocket can deal with chain slack for a good tight fit of chain on jackshaft sprocket.
Now the jackshaft will be running in reverse at its other end on other side of bike. Hope that made sense...
There are some super-heavy duty centrifugal clutches made for racing go-karts stateside, but pretty high dollar! A good Comet clutch should do it without going to mega-bucks.
The Clinton engines were okay and durable overall but most low power versions had plain bearings [bushings] instead of ball bearings for crankshaft. The original Clinton engines that were used widely in go-karts and mini-bikes in late 50' to early 60's were actually decomissioned Maytag washing machine motors, used in outlying areas of the country that didn't yet have electricity in the late 30's to early 50's.
The crank bushings can be swapped for ball bearings. Many Clinton 2 strokes were a single casting of crankcase, cylinder & head so it was difficult to up compression without using a pop-up piston or welding up the original piston crown. Ones with separate head could of course be milled [or laboriously sanded!] for high compression. You can stuff the crankcase which makes a big difference in power. The early Clinton carbs were marginal and most guys swapped for a fat Tillotson to jam in more mixture. Porting intake and exhaust ports is really easy and makes a huge difference in power. Some guys even drilled engine casting to add another intake port! With roller bearing crank, ported intake & exhaust, straight through exhaust header, stuffed crankcase and a large Tillotson carb it's easy to double horsepower or more and high compression piston or milled head boosts that up too while still being reliable.
Last I looked, over a year ago, there was a guy stateside that specialized in vintage Clinton parts, don't know if he's still around. He was somewhere in the midwest, maybe around Clinton, Iowa where the original company was.
Yeah I think when he says reverse the drive he meant swap over from left to right as most engines these days are on the left and his Clinton is on the right. He was also thinking of reversing the direction of rotation on a 2 stroke by altering the timing and turning the engine round 180 degrees which would then drive from the r/h side but the pull starter wouldn't be rotating in the correct direction.
gilburton wrote:Yeah I think when he says reverse the drive he meant swap over from left to right as most engines these days are on the left and his Clinton is on the right. He was also thinking of reversing the direction of rotation on a 2 stroke by altering the timing and turning the engine round 180 degrees which would then drive from the r/h side but the pull starter wouldn't be rotating in the correct direction.
