Thread for alternative engines

I was deeply into R/C several yrs back and these engines(Chinese) were just beginning to show up. There were similar engines in use made by various companies Desert Aircraft, 3W etc., that were excellent but pricy engines. Their HP claims were accurate.

The Chinese engines were initially problematic, but I assume that probably been worked out by now. The smaller twins while smooth and having a cool factor didn't produce as much power as a good single. Especially the little 40-60cc. Maybe that has changed.

All that said, a 80-100cc might make a pretty neat MB. Cooling wise(free air) I just don't see any way it would work out except in a transverse mounting. Some what of a challenge. In an aircraft the prop blast(on the ground) and ram air cools them well. It will take movement to cool them on an MB and at a pretty decent clip. Extended stop and go would not be good. The 2strokes are less tolerant than a 4stroke under these conditions. I'm sure L2 you remember the cooling "eyebrows" I added to the transverse Maytag to catch more air. The longitudinal Maytag still has its cooling fan and works well as is.

Not trying to discourage anyone from a build just pointing out some limitations that should be considered.

A good running well engineered 100cc MB based around one of these would way cool! I certainly would leave it carbureted though. They run fine that way.
 
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This engine is way too big for even the strongest mountainbike frame, and thus it's better suited towards full-sized motorcycle builds, but a horizontally-opposed twin Briggs, fuel-injected and twin-turbocharged using RHB3 turbos, would be bad*** to stick in a board track racer frame.

Of course the boost would have to kick in on the low end because these motors from what I could look up are dominant in the low-end. CVT would also need to be tweaked for greater responsiveness down low too, and the drive and rear sprockets would need to be geared with a torque bias.

Engine in action: https://www.youtube.com/watch?v=lrCA2ow4PPE

....Of course a 12hp single-cylinder Briggs would fit in some frames easier, but still.
 
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This could be used for an extreme trike build as well, provided the transmission's an auto, and rear axle can handle the torque. As for the brakes, those could be linked to a trigger on one of the handlebars, and then the gearshift could be a thumbswitch. Throttle would be handled by the twist of another handlebar. Motortrike frame would need to fit a 3.9l I4 that weighs almost 800lbs though, in addition to a radiator, and possibly an intercooler and aftercooler for the turbo. Frame would also need to handle heavy vibrations from the 4bt as well.

http://cumminshub.com/4bt.html
 
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Also, here's a 53cc boxer-4 that puts out 4.1hp@8krpm if anyone wants to try fitting a trans to it and fitting it in a frame. Gearing that would best cater the high redline would be recommended. Quad exhaust could be going out through two straight pipes on either side of the frame.

http://www.osengines.com/engines-airplane/osmg1320/index.html

Vid of it in action and how it would be expected to sound going down the road if pulled off. https://www.youtube.com/watch?v=EpW3acWVkGg

69cc radial if you have room in the frame and really want to go insane: http://www.osengines.com/engines-airplane/osmg1307/index.html

Vid of the radial in action: https://www.youtube.com/watch?v=ZoHu6DWNwRo
 
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msrfan said:
Good thread Ludwig. I like alternate engines also. This 24'' Schwinn has a Stihl 4hp backpack blower motor which was a challenge to mount, but shows promise. It is a 4Mix engine that is a 4 stroke running on mixed fuel. The Comet drive didn't work so I installed a Cobra gokart clutch and will be experimenting with a larger carb soon.








I also have some water pump motors that are really compact and deliver 3-4 hp.
Alternate drives interest me. Like using an outboard boat motor lower section for a shaft drive bike.
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How did it end up? It looks very good from here.
 
Okay Lud, my motor mounts measure 2 7/8'' inside and are bolted to the original supports on the left and to the pull rope mount on the right. Over height is around 8''. I measured it in the bike, so if you want more detailed sizes I can dig out my spare engine and be more accurate with photos. Be glad to do that for you.
 
I was wondering what the width is in the frame, and whether it could go down by wide pedals like an old Cucciolo unit.

DUCATICucciolo-2070_1.jpg


This is the best set of pics I could find to show the size.

http://www.ebay.co.uk/itm/1953-duca...d-autocycle-cyclemotor-minibike-/360409162327
 
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It has something about it of the pedal start 35cc moped engine I found a while ago. It may have ancestry in the Honda Novio.
 
Ludwig II said:
In searching for info on the Norman engines, I ran across the Stuart Turners, and also an odd one I'd never known about. Royal Enfield made a flat twin 350 2 stroke genny engine.

Surely, in all the production of America, there must have been a flat twin 4 stroke by somebody?
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Ludwig,

Check out these two flatties offered for sale right now on eBay by the same seller. The green liveried one is indeed a Stuart Turner. That ex Sunderland Flying Boat genny engine is just about the sweetest thing I ever saw. I only just bid on and won a Gnome et Rhone 2-stroke yesterday on eBay or I'd be sorely tempted with either of these beauties.

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s-l500.jpg
 
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