50cc GY6 on a Bicycle??

Look at the size of the driven gear. It's huge. I know some of it is housing/cooling, but wow. Real monster
 
Dan said:
Are the carbs gravity fed?
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Yes mine is, the fuel tank is higher than the engine and under the seat but, the ruckus type that have the tank under the floor pan use a diaphragm pulse type fuel pump like what you would use on the racing karts with a tank up front under steering wheel.
 
Hoely Cap & Gown, Batman! Burnouts with a belt driven gear box. That is just amazing.

Thanks for posting MapMan.

I measured once, but forget. Width of the 50cc, any one? Think it is wider than wide cranks. If it would fit, not likely, but could be mounted as intended, below and low.

And be easy -er to fab a mounting. Me thinks. Carb question was if rack-mounted. Kinda hate gas so close to the head. hehe, the "Flaming Failure" would not be a cool nickname...
 
Dan said:
Hoely Cap & Gown, Batman! Burnouts with a belt driven gear box. That is just amazing.

Thanks for posting MapMan.

I measured once, but forget. Width of the 50cc, any one? Think it is wider than wide cranks. If it would fit, not likely, but could be mounted as intended, below and low.

And be easy -er to fab a mounting. Me thinks. Carb question was if rack-mounted. Kinda hate gas so close to the head. hehe, the "Flaming Failure" would not be a cool nickname...
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LOL... Yeah Dan burnouts and evafang...!
 
The kids in Hartford try to sup-up their scooter/mopeds. Nothing like that. I really am amazed a scooter can do that.

Almost scary on a bike, me thinks. Doing ratios. Gonna be cool
 
I think there is even a version with built-in bicycle cranks...but I'm not positive.
These engines are far too wide for any normal bike crank, but it can be done with some creative thinking
 
Cant find dimensions but keep finding a ton of information & upgrades.

Searches related to how wide is a gy6 50cc engine
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Tomorrow I'll measure my 150cc GY6 and see what it is Dan, the 50cc is narrower but I don't know how much.

As far as gear ratio is concerned, I really dont think that would be hard to get done, I think I would probably use a heavy duty 20" BMX wheel on the rear and a high strength bmx tire and tube and then go with a 24" front wheel, the 20" on the back should be easy to gear for being that it's not much larger in dia than the 13" wheels that are on many of the scooters like mine and some of them actually have 16" wheels on them, normally the output shaft direct drives the rear wheel so I'm gonna say very little reduction will be needed.

I could be wrong but since the scooter wheels aren't that much different in dia than a 20" bicycle wheel, if this size wheel was used and the fact that a bicycle weighs so much less, even a slightly higher ratio than the scooters have would possibly work OK on a bike.

Like I said I could be wrong but this is my thinking right off the top of my head.
 
maniac57 said:
I think there is even a version with built-in bicycle cranks...but I'm not positive.
These engines are far too wide for any normal bike crank, but it can be done with some creative thinking
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Never seen any of the GY6 variants with peddles, but there very well could be something out there that is similar that does.
 
Such tidy lil power plants, think even an 80cc would be passable to the eye on a bicycle.

But man, how cool would it be if the 50 fit the horizontal X axis of wide pedals? approx. 7.5" Could easily (haha, famous last words) make a bracket to "hang" the engine below.

Forgot it probably needs to be off-set....


Gotta just get one. The dry-erase board that is my brain is full, lol.
 
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Cool, Lud! TY. One pic shows the, I think brake assembly, can be removed so the engine could be close if not centered. And the shaft could be adapted to receive a sprocket. Or replaced.

2nd & 3rd pic of GY6 pictures
 
I wonder if anyone has considered what I have seen done, but can't find the page, of chopping the back off the engine part, and running a short belt to a fixed pulley like an old Mobylette, and then a chain to the back wheel. You'd have to factor a clutch in of course, but that can be done through belt tension.
 
Dan said:
Cool, Lud! TY. One pic shows the, I think brake assembly, can be removed so the engine could be close if not centered. And the shaft could be adapted to receive a sprocket. Or replaced.

2nd & 3rd pic of GY6 pictures
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The output shaft is splined on all of them so all that would be needed is a rear wheel to remove the splined insert from and then weld the desired sprocket on to that spline is what I would be doing I think.

Here is a pic of the little 50cc version

all_50cc_GY6_engine_parts.jpg
 
Could broach it. Then sprocket would just slide on and be held by a coller.

But must be removable so could, and I think optimally, replace with a keyed shaft?
 
My dad used to take shafts and weld them up to a larger diameter and then turn them down to desired size and then cut a keyway in it.

Yes a bit more effort but that would make for a dang good setup that would be easy to swap sprockets on, the shaft isn't hard to take out of that little gearbox, they actually make a couple different ratio gears that can be swapped out in them for eother higher or low final ratio, and the gears and shaft is actually purdy cheap.

the shaft is to small to put a keyway in I would think, but welded up and then turned down to 3/4" would probably be perfect.
 
Thats purdy cool. Wish we lived closer map. This sounds like it is gonna be a fun project.


Swapping ratios is great. I wanna try it with 26" wheels and your right with a smaller wheel would work better but kinda restricting in choices. Well, for my bike harum any way.


but really exciting endeavor.
 
To me, the variator drive is worth a lot of hassle to get into a bike! Even the 50cc is easily good for 50mph with the variator using engine power to best advantage.
The chain drive ends up with close to normal gearing on the four wheelers, so it's not too far off what you need. Some careful gearing research should make this a very user friendly engine choice!
And like I said, with the aftermarket hop ups and big bore kits available for these engines, you can easily get a seriously fast powerplant!
 
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