M
MrCrowley
Guest
Ok, for my lawnmower engine idea, I pulled the trusty, rusty lawnmower out of the shed yesterday to look at it from the viewpoint of propulsion and not mowing grass. The biggest problem I have is that all my motors 26hp, 16hp, and 6.5 hp are all bottom shafted. However, thats great if I decide to use a riding mower transaxle. With taller bicycle wheels, is should gear up to bicycle speeds. Pulleys would gear it higher if need be. This would then be mounted in the trailer/ or side car "frame". This way, the fan belt from pulley to pulley can always act as a "clutch" using the transaxle route. This is great if using riding mower systems.
However, this little 6.5 intrigues me because it has a side shaft PTO gear for self propulsion- and gear reduced already. I think it is a small gearbox bolted to the bottom of the 6.5. I turned the blade by hand, and it is either 8:1, or 9:1 reduction (was getting dark). It is from a circa 2000 Scotts pushmower. Is this an ideal reduction speed? Im thinking it would be enough, and any more gearing changes could be accomplished via the jackshaft/ fan belt pulleys.The cool part is, I could use a fan belt with a cabled tensioner as a clutch like a riding mower, and go straight bicycle the rest of the way. fan belt jackshafted to MTB triple rings, via chain to a MTB rear wheel with maybe dura ace cassette? Hmm. A 30 speed! This should negate any slightly of gearing problems. More than enough to pull a load straight up a hill, and more than enough to still apply engine power on the downhill white knuckle rides
Also, if I could use a MTB suspension fork to mount the wheel, having a true bicycle setup on this separate frame, the rear derailleur could tension the chain as the suspension flexed. Wohoo!
If I decide not to do any of these, I may have to go and buy a true side shaft motor. I do still have a weedeater engine I could yank, but I dont think its enough power for a trailer/sidecar plus stuff. To me this really seems do-able, or am I just crazy? I think I should really spend a couple of weeks with the gearing calculator for every gear before fabrication begins.
However, this little 6.5 intrigues me because it has a side shaft PTO gear for self propulsion- and gear reduced already. I think it is a small gearbox bolted to the bottom of the 6.5. I turned the blade by hand, and it is either 8:1, or 9:1 reduction (was getting dark). It is from a circa 2000 Scotts pushmower. Is this an ideal reduction speed? Im thinking it would be enough, and any more gearing changes could be accomplished via the jackshaft/ fan belt pulleys.The cool part is, I could use a fan belt with a cabled tensioner as a clutch like a riding mower, and go straight bicycle the rest of the way. fan belt jackshafted to MTB triple rings, via chain to a MTB rear wheel with maybe dura ace cassette? Hmm. A 30 speed! This should negate any slightly of gearing problems. More than enough to pull a load straight up a hill, and more than enough to still apply engine power on the downhill white knuckle rides

If I decide not to do any of these, I may have to go and buy a true side shaft motor. I do still have a weedeater engine I could yank, but I dont think its enough power for a trailer/sidecar plus stuff. To me this really seems do-able, or am I just crazy? I think I should really spend a couple of weeks with the gearing calculator for every gear before fabrication begins.
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