4 - stroke Schwinn Stingray Chopper occ

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Related to this post: https://motoredbikes.com/threads/pr...chopper-and-im-looking-for-some-advice.50872/

Donnor bike:
IMG_20171001_111755.jpg


Since this is not being an standard build (as expected) I'm going to describe how I'm solving the issues that I'm having, I hope it will be useful for someone.

First thing, choosing the motor kit: after digging and asking around I decided to go for
I ordered this kit: http://www.bicycle-engines.com/49cc-4G-T-Belt-Drive-Complete-Gas-Powered-Engine-Kit.html
I didn't know if to get the 100 or the 80 tooth pulley, I asked on the chat that they have and.... I believe the person behind didn't know much about what she was talking about... I asked which configuration will be faster and she told me the 100 tooth... After checking the manual that comes with the engine, that is wrong, 80 has a "faster" ratio, 100 is for better hill climbing and torque. Because of this I ordered a smaller sprocket (36 tooth), I'll get a Engine rpm to bike wheel rpm ratio of 18, close to what you get with the 80 on the transmission and a 44 on the wheel (17.6).
[UPDATE]
After contacting BE, they are sending me a 80 tooth transmission to exchange with the 100 one, I don't have to pay for anything, amazing customer service!

IMG-20171006-WA0006.jpg


Pieces I've ordering so far (updated on Apr 2018):
- 49cc 4G T Belt Drive Complete Gas Powered Engine Kit - 80 tooth transmission (from Bicicle-engines) (firt transmission was a 100 tooth by mistake, exchanged with a 80 tooth)
- 2 Piece Muffler "Poo Poo Pipe" Deluxe For 4 Strokes
- Flexible muffler tube (eBay)
- 36 tooth sprocket (Amazon)
- 40 tooth sprocket (Amazon) <- using this one
- Sunlite D-Cruiser Handlebar, 32" W x 13.5" H x 7/8" - Hi-Rise handlebar
- 2 x 2,5 inch U-clamps with nuts and washers
- Front wheel, being a 24'' back wheel with free-wheel to install disk brake
- Disk brake kit for free-wheel (BlueSunshine Front and Back Disk Brake Kit - 160mm For 80cc Gas Motorized Bicycle - Amazon)
- Front fork with suspension

First thing is holding the motor to the bike, the engine bracket that comes with the motor si not compatible with the frame, and indeed, there is no much room to play around in the frame, so I have to remove pedals, bike chain and the chain cover, after that still, really tight, so I cut a portion of the chain cover holder, like in the picture:

IMG_20171007_153759.jpg


After thinking about different options, I come up with a solution, using the central part of the bracket drilling 4 holes (picture only has the first two) on each side of it, so I can use 2 u-clamps to hold it to the bottom part of the frame of the bike

IMG_20171008_214141.jpg


After first try, looks like it is gonna make the trick, the round part of the u-clamp is kind of the same round that the frame, so it adjust well, on the other side, part of the unthreaded u is coming out of the bracket, so I need some washes or something, and of course, I'll have to cut the u, it is way too long.

So far Is what I did (as October 8th). I'll keep updating as I work on it.

November 5th update -> https://motoredbikes.com/threads/4-stroke-schwinn-stingray-chopper-occ.51001/#post-451003

Video of the first start of the motor (Nov/05) -> https://motoredbikes.com/threads/4-stroke-schwinn-stingray-chopper-occ.51001/page-2#post-451198
 
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Keep an eye on those fork tubes. You just created a major stress point.
 
hey KC, is there a certain place you buy your extra long throttle cables? i have a build going that has 22” ape hangers on it and i can’t seem to find a long enough throttle cable.
just buy a brake cable an with some of thrpttle parts that came with it an some housing make you own
 
Hi guys..
i just put one together... used a 80cc 4stroke champion motor..
it runs great.. but its sackless.. i have 11T on the clutch and 48T in the rear.
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Hi guys..
i just put one together... used a 80cc 4stroke champion motor..
it runs great.. but its sackless.. i have 11T on the clutch and 48T in the rear.
View attachment 101042View attachment 101043View attachment 101044View attachment 101045View attachment 101046View attachment 101047View attachment 101048




A couple of things to consider, is the governor still in the motor? Disable the low oil shut off. And, is the throttle opening all the way. the video it is really hard to tell, so a couple of still photos of the carb would help, one just at rest and the second at wide open, it doesn't have to be running.
 
A couple of things to consider, is the governor still in the motor? Disable the low oil shut off. And, is the throttle opening all the way. the video it is really hard to tell, so a couple of still photos of the carb would help, one just at rest and the second at wide open, it doesn't have to be running.

throttle is def opening...
oil shutoff is still connected.. but the motor isnt cutting out...how will disconnecting that help ?
the Governor is still in the motor... its def feels like its just not a big enough motor..
this motor is for a champion pressure washer.. and when it was in there it def was running at full throttle..
the throttle is connected to the arm between the gov and the carb.. it was the easiest way to get the cable connected.
if you look at pic 6 and zoom in, you can prob see it.. that was when i just got the motor in and had the tank off so i could run the throttle
cable.
 
Yea, get rid of the governor, do you know how to do that? Do you have any fabricating skills? I put a PZ19 carb on mine to waken it up, plus a pipe, but I had to make both the intake manifold and the exhaust.
 
Max torque clutch and no governor that should do it.
In the first clip the clutch sounds horrible shouldn't chatter that much.
 
Max torque clutch and no governor that should do it.
In the first clip the clutch sounds horrible shouldn't chatter that much.
i think that noise was just the washers ... that said, is a max torque a brand name? or are u saying in general?
i just got this clutch off amazon because it was the right size for the crank..
i was wondering if i could change the spring on it, if that would matter..
 
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