50cc GY6 on a Bicycle??

[mapbike]

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.

Yeah I'm all alone around here when it comes to most of my hobbies.

Im just excited to see what you come up with on the whole deal, only thing I might be in trouble with would be the electrical, I wouldn't know for sure how to get he cdi all wired up, Im a mechanical fella but electrical is m weakness, very little knowledge about it.

 

[Dan]

Maniac, only find monster big CVTs or whole quads looking for variators. Any other keywords I should search with or do ya have any links handy?

Mapster, I hear you on all things electric. Seriously, take an online course with me. Will find us a free one. Kinda fun taking these things. (I collect meaningless certificates) and way more fun and motivating when ya do it with other folks.

 

[Davezilla]

For CVT parts. Treatland.tv has a Lot of parts and upgrades like all the different weights to set the upshift rate etc, and they also have a decent selection of the driven variator springs to fully customize for most mopeds, and with the GY6 being as popular as it is, finding cvt upgrades should be really easy from treatland, ebay, and other scooter parts places online.
If someone needs a monster CVT like for a 40hp engine (or larger), look up "snowmobile clutch" on ebay or google and you'll find all the parts you could use.

I got this little engine from treatland last summer and it has a built in CVT with plenty of upgrades available, they even make new belts for it again so no problem if the belt wears out... https://www.treatland.tv/franco-mor...start-eng-p/franco-morini-complete-engine.htm ...Got this one before deciding what to put it in and I'm still undecided, it's about twice as wide as the China Doll engines so I'd need some really wide pedal cranks for a bicycle, but something like the Stingray or one of those 26" chopper type frames might work.
As far as GY6 upgrades tho, there's plenty out there for both the engine and CVT.

 

[Dan]

Mapster, I posted a link and invite in the free ejimacation thread for a free course;

http://motorbicycling.com/showthread.php?t=56955&page=2

 

[mapbike]

Mapster, I posted a link and invite in the free ejimacation thread for a free course;

http://motorbicycling.com/showthread.php?t=56955&page=2

Got it... looks like a good course for people like myself that are electronics challenged..LOL!

 

[cannonball2]

Hooking up the CDI is not a big deal it pretty simple. There are two versions an AC and a DC The DC is fed by the battery while the AC is fed by the alternator. Just have to know which one the engine is supplied with.

As far as variator tuning, a DR Pulley is about the best. It has a bigger driven face allowing higher ratios as the belt can climb higher. Also adding a few mm to the drive belt size will allow the belt to travel there as the rear driven sheave stops it short with a stock belt. I guess you all realize the clutch is in the rear sheave and not on the engine. Clutch springs come on various rpm ranges, and there are several main springs for the rear sheave to tune how it responds to the variator. I like my CVT to get to the upper ratios pretty quick. The big bore engine has the power/torque to handle faster travel to high ranges. Therefore I run fairly heavy weights. A typical take off for me is WOT and hold it there until the speed I want is reached(pretty quickly too). I have carefully tuned the variator to allow the engine to get to its max torque range. The engine immediately jumps to around 6500rpm and just stays there while the variator makes the speed happen. Once the engine unloads at around 65mph then it will rev on to around 7500 which allows the variator to finally push the belt to the full extent of the drive face and topping just north of 70mph. The design of this little power unit is pure genius!

 

[Dan]

Great information, CB. Thanx!

 

[maniac57]

I'm not sure what Chinese quad brands have the gy6 motors. I just know there are a bunch using basically the standard street scooter driveline with the added chain drive box. They just hang the whole scooter driveline off whatever mounts the quad wants. The engine is the same but drives a chain to the rear axle rather than the usual rear wheel.
I'd guess anything in the 150cc area is a good candidate to search for, then just look. The scooter motor quads are easy to spot from the fan shroud shape. They come in 50cc to 150cc or so under dozens of names.
http://www.alibaba.com/product-detail/Quad-150cc-ATV-automatic-with-GY6_606608347.html


Here's the chain drive box:
http://ezatvparts.com/gear-box-150cc-atv-gy6-style-engine.html

 

[Dan]

Manual, Maniac! Manual! Could you have discovered an adaptable, already (inexpensive) mass produced, manual MB powertrain engager!?

I have a lathe and mill. ....... hmmmmmmmmm

 

[cannonball2]

Heres a link to an atv engine. It has reverse which adds considerably to the gear box width. Notice the output shaft. It appears to have the same splines as the scoot wheel. There are 18 spline(as I remember) and 19. I bought a wrong splined wheel, mine are 19. The point of this is that more than likely the sprocket from an atv might fit the common scooter wheel shaft. Would be a simple matter to saw the shaft at the right point and drill and tap for a retaining bolt. A bike doesn't need the atv engine if this is true. Its more complex, heavier, and more $$. There are plenty of manuals for free on line I have both the 50 and 150cc loaded in my computer. Not sure how to attach them. http://www.ebay.com/itm/150CC-GY6-A...Parts_Accessories&hash=item5645a65abf&vxp=mtr

 

[Austritch]

Hey! I am building a fat tire (mongoose dolomite) custom frame and gas tank bike. My mandatory specs were that it had to have disc brakes front and rear, 4 stroke motor, and shift with no manual clutch (shifter kit from Bike Berry). The problem I am having seems to be that the 49cc motor (also from Bike Berry) is under powered for the gearing and is frying my centrifugal clutches. I am thinking about going with a 150cc Gy6 motor. Do you think this is the right thing to do? Perks to the Gy6 motor are that parts are readily available, speed will be more comfortable, and a kick starter. My build is more of a motorcycle style than a pedal bike. I am still trying to utilize the original rear cassette and shifter so that I may run through all 7 gears for a more useable ride. Rather than going with a larger single gear, I am thinking about using a more powerful motor. Hence the 150cc Gy6. Does anyone have any experience with using a Gy6 150 on a motorized bicycle?

While I have the bike on the stand, it will run perfectly fine and shift through the whole cassette. But while under actual load, it barely moves under its own power.

 

[Ludwig II]

My first question is what the reduction ratio is between the output of the engine and the largest of the sprockets you have. If the gearing is too tall, that will explain the fried clutches.

Can someone give a ballpark set of figures for the right number of teeth on the driving and the driven?

 

[cannonball2]

You haven't given much info on how the bike is configured. Generally there is a jackshaft required to transfer the drive to the derailleur, and the ratios are very important as L2 has indicated.

I am assuming you are running the 4stroke engine. Depending on which kit you bought you may have the one with the 3:1 pocket bike trans. This kit has too little primary reduction, it should have a 5:1 reduction to make it work well. I have one of these. When I bought it I assumed a 5:1 box. They don't tell you its a 3:1. Maybe this is part of the problem?

I have a ton of hands on with a 150cc Gy6 in a Honda ruckus clone scooter. I extensively modded the engine and variator. It will easily show the north side of 70mph.
They are wonderful powerplants. However for modding to a bike it will require some pretty good fabbing as its an engine/trans unit that is also the rear suspension. I suppose the rear triangle could be removed from the bike and the Gy added to the frame some how. But running a scooter sized wheel would be required as the final ratio would be way out of wack for a bike wheel. Not trying yo discourage you if you have the skills go for it. Just pointing out a few facts.

 

[Austritch]

Here are some pics of the build:

 

[Austritch]

Even more pics:

 

[Austritch]

And more pics:

 

[Austritch]

This is the exact gear kit that I ordered:

 

[Ludwig II]

This business with the transmission case, why not cut out a section in the middle and use a shorter drive belt? It should be possible to make up brackets or flanges as well to bring the cut faces to each other, so giving a clean and safe primary drive to what is now the 1st reduction in a 2 stage transmission.

 

[cannonball2]

While that may be plausible L2 it would be quite a bit of work.

That still leaves the issue with gearing being based a 10/12" wheel. Not an issue if running a smaller wheel in the rear is acceptable. There are plenty of optional final gear sets but I doubt any low enough to accommodate a bike size wheel. Of course one could run a small front wheel to balance things. Might be a 21st century Cushman.

Austrich, the reduction I am referring to is the case on the engine. It looks like a 3:1, The 49cc really needs a 5:1 and the more expensive kits come with them. You can determine by removing the reduction(4bolts) and counting how many turns the clutch drum makes for one turn of the sprocket. I'm betting 3.

 

[curtisfox]

And more pics:

First picture looks like you have a small sprocket on the engine side and a big one on the drive side. That is stepping up the ratio, should be changed around with the big gear on the engine side...............Curt