50cc inline twin 2 stroke

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Will'smotobikes19

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Hey guys just want to talk about an idea I had. They make snowmobile engines that are multiple cylinder 2 strokes right?. What if you could scale one down and have an inline twin 2 stroke say 50cc so 2 25cc cylinders wouldn't that be cool? should rev really high too. Has anyone attempted to make such an engine? I was kinda inspired by the old 50cc honda race bike but that was a 4 stroke. It should have more power than a regular single cylinder 50cc engine maybe to make a prototype you could use 2 25cc cylinders from weedeaters? and make a prototype crankcase any ideas appreciated. I believe they make similar engines to what i'm saying for R/C purposes.
 
Here's a 52cc inline twin
s-l400.jpg

Would be too wide for an in-frame engine, but might work on trikes.
Edit: its 220mm (8.66") wide, might make it fit using a pulley on the output shaft and manually engage the engine to the wheel with a tensioner on a lever.
 
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That's cool I wonder if you could fashion a centrifugal clutch on it or have a similar transmission to snowmobiles. You could make a custom exhaust that goes from both cylinders to one expansion chamber. The width is no more than my 79cc predator with the clutch and pull start. Do you have a link of anyone that sells that engine? or similar. It looks like the output shaft isnt very long and I wonder if it would take the load weight of a person and a bike since its probably meant for RC nonetheless it would be a cool bike. UPDATE: I found sellers for the engines quite expensive $400+ and made in China too, I think it would be cheaper to build a prototype based on it with weedeater parts.
 
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Generally speaking, R/C engines are probably not all that practical for a mb, since they are oriented in a front to back configuration, instead of sideways, like the china girl or predator motors. There are many very, very cool gas r/c engines, however, and they usually make a surprising amount of power for their size. Here are a couple of neat little engines just fyi:
https://hobbyking.com/en_us/gtt70-engine.html like that one, it's a 70cc 2 stroke twin or this other 5.5hp, 53cc twin
https://hobbyking.com/en_us/5-5hp-53cc-twin-cylinder-gas-engine.html
For some reason this page on this site is acting strange, but this is the GAS engine page, no glow engines here, but they have 2 and 4 stroke engines in a range of sizes, it's a cool resource, and you never know, you might find something you can't resist, even if you can't really use......
https://hobbyking.com/en_us/power-systems-1/gas-glow-engines/gas-engines.html

Bear in mind that good old china girl only makes about 1hp, and some of these are really impressive for what they are. There is even a 10cc engine that makes 1.9hp!
Also, I would remind you that china girl has built in gear reduction, so finding a practical transmission for an r/c motor, or the motor that started this thread will be difficult. I mean, lets face it, wtf are you going to do with a 12,000rpm output?
 
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Oh cool a 3 cylinder I'd like to make an engine something just sounds cool about a motorized bike with a multiple cylinder 2 stroke I have a few old weedeaters and got the idea from them, maybe I could use 2 25cc cylinders and cast a crankcase for it based off the original ones just longer then there would have to be a crankshaft made.
 
I think I saw that video the other day the first 52cc engine at the top of the thread could work you'd just have to have a longer shaft and take off the golden bracket and come up with a transmission and mounting points and you could use a wide pedal crank, the only thing I don't like about it is the price you could buy one of the 9hp ktm 50 clones for that much. But who knows they might be about the same power
 
Mind your speakers. :D

Yep sounds pretty cool to me. :cool:

lol. 12.5cc a cylinder! microscopic!

the honda cbr250 is a joke. its missing three cylinders...

whereas the original cbr250RR, aka mc19-22...beast....four cylinders, redlining at 20,000 +

the sound of MAGIC! oh. yeah. i forget. they were only released in japan and australia... suckers!

now they think theyll get increased sales by making the latest version a twin...still missing two cylinders!

(or four, if you like the...rc166 wasnt it? the six cylinder?)


meh. what you want for the motorised pushy is a Vtwin...like a 1/5 harley engine...blat blat blat blat...
 
A guy on YouTube built a 175cc v twin, franz flyer he called it I think he also built a homemade 392cc v8 bike the reason im interested in a inline 2 2 stroke or even a inline 3 is thats what i'd like to put on a bike since there are very few of those type builds
 
i like the idea of horizontally opposed pistons, myself... just like a commer knocker but smaller...

the challenge is getting the crank to squeeze in between your pedals. gearbox. clutch. all that jazz.

hell, someone even tried a rotary build on here somewhere... 160cc of raw rotary bwap!

the only real source of small multi cylinders is RC plane engines...and even the four strokes are oil thirsty. run on a 10: pre-mix.

which will require flywheels, clutches and that damn gearbox again.

v-twin is the best layout cus its got the best natural balance and its narrow.

twostrokes make it hard because you need either both cranks to be separate, or both pistons have to be at TDC.

be fun to use to honda or fuji/subaru/robin 25cc fourstroker on a custom crankcase...

hope you have a machine shop or youre going to be spending a LOT of money...
 
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