which weedeater engine has the output shaft facing to righthand side?

oldschool1980s

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when most weedeater engines in USA are taken apart to just their engine without the driveshaft extension and the bottom end that does all of the work, most of the 30 to 33cc Two cycle engines ive seen has the pull starter on the right hand side if you was to turn the engine so the output or the crank rotation is facing on the left side as a horizontal shaft engine like that of a Briggs & Stratton horizonal shaft motor for a go-cart or a mini-bike, I have seen some weedeater or small engine leaf-blowers to where the pullstart would be on the LEFT hand side, so the output crank would be facing on the RIGHT SIDE, which is ideal for replacing a bicycle crank with an engine since the bike sprocket is on the right hand side, so you're going to need an engine to where the output crank is facing to the right side instead of to the left,I have bought a 80cc GasBike motor on Ebay for like $100, but the sprocket kit for the rear wheel to be mounted on the left side of the rim is such a pain in the butt to bolt on correctly, if the sprocket rag joint install isnt done correctly to where the bike's factory coaster brake can still be used after mounting the Gas-Bike's rear sproket on the left hand side of the rim, that lopsided install wont line up with the chain and even without the Gas-Bike's engine chain being used, that improper sprocket install will chew up your bicycle rear axle bearings,which brings this small engine topic back to what 30-33cc or even a very small 4 cycle engine leafblower will have the output crank facing the right side,so the pullstarter is on the leftside, and the engine running crank's rotation is still clockwise, but will be on the right side instead of the left side.
 

tom3

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Whew. But those little motors run pretty high rpm, running a single drive would be near impossible. I'd suggest a jackshaft deal, get the drive on the left as you describe, jackshaft across to right with additional reduction.
 

bertsmobile1

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the cheapies have the pull start on the drive side.
The better ones have the pull start on the opposite side.
With the exception of Ryobi most of the cheapies have a 1/2 crank
The more expensive engines have a full crank shaft
 

oldschool1980s

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the cheapies have the pull start on the drive side.
The better ones have the pull start on the opposite side.
With the exception of Ryobi most of the cheapies have a 1/2 crank
The more expensive engines have a full crank shaft
bertsmobile1, does all of these small engines cranks when running, does all of the engines rotate in the clockwise direction to pull a chain or a belt drive? i wouldnt be surprised if i was to pick up a used japanese motor that still runs, only to see the crankshaft rotating *Backwards/counter-clockwise*🤪 "D'oh!" >=(p
 

bertsmobile1

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They just about all rotate clockwise
However the bevel gear at the end of strait shaft trimers reverses the direction of rotation.
They used to rotate either way because the flex shafts used to come either right or left hand lay.
 

tom3

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Look at the drive end and pull on the rope, will show you the rotation direction. Can probably see this in a picture actually.
 

oldschool1980s

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Tom3,you mentioned that a bicycle like the adult sized 26 beachcruiser having the factory coaster brake rear rim, would not be able to handle the high RPM of such a small 21cc to 33cc two cycle engine? why not? if properly mounted with a engine mount looking like the tube frame engine mounts a small to medium sized motorcycle or a moped uses, what part of the bicycle will not hold up to that small engine doing about 15 to 35 miles an hour? i ask because theres a gasbike 80cc engine on Ebay for $94 to $100.00 that is basicly a modified moped engine to fit either a open frame mountain bicycle, or the older BeachCruisers, and the gasbike kit even comes with a square frame tube mounting adapter for bikes having the square frame,What i didnt like about that gasbike kit is how the back sprocket kit having the 3 curved backside mounting plates that comes with that gasbike engine, is *supposed* to be bolted together to make a one piece plate to be bolted onto the left side of the rim, the issue here is that the factory coaster brake arm has to be removed for the rear sprocket kit to have clearance to fit onto the rim,and those 3 back mounting plates when trying to put the sprocket kit together doesnt always get put together evenly to make a flush mounting plate back support for the front side, the sprocket on the outside of the rim to be bolted to the backside plate, the rear mounting backplate gets lopsided to where the front sprocket cannot get centered for that chain to work, it would be much easier to buy a sprocket hub gear having the bicycle 1/8 x 1/2 sprocket teeth and put that sprocket hub onto a small single cylinder motor to run the chain either back to the wheel, or if mount the engine above the rear wheel using like a welded in thick plate, run the engine's chain down to the rear wheel sprocket-which would make the bike frame into more like a scooter like those in Italy or somewhere.
 

tom3

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Just some quick math. Typical weed eater motor at output speed might be 10,000 rpm. Usual 26" bike tire/rim, 10 : 1 motor speed reduction. Bike would be at about 85 mph if that 2 hp motor would pull it. That would be a 2" sprocket driving a 20" rear sprocket. Better a powerful chain saw engine for that and the jackshaft to get a reasonable final drive. Many old gas powered bikes used a friction wheel against the tire to drive it at reasonable speeds. Or a built in transmission with reduction gearing. Could be done, be lots of fun once it's figured out. Battery might be the better way to go these days though.
 

jp1961

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Hi,

To get the pull start on the left and clockwise rotation,(on the PTO side) you're looking for, I'd say a chainsaw would be your best bet. Just be aware some chainsaws have the coil mounted in the housing (I.E. Poulin Wild Thing), not on the engine, so you'd have to use the whole housing for the conversion.

I checked my Tecumseh TC200 engine, but the PTO spins counterclockwise.


Regards

Jeff
 
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