after a rear mounted motor that drives wheel by belt and large pulley o the wheel?

joshua97

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hey iv seen a few people here with a rear mounted motor -around 30cc that drive the rear wheel by what almost looks like a smaller rim mounted onto there wheel and a belt driving them. just wondering if anyone can shed some light to where i can get one and what thy cost or if i can get a kit without an engine? i have seen a few kits but they are around 700$ thanks
 
What you saw was probably a Golden Eagle Bicycle Engines kit,G.E.B.E.
They're kinda pricey, but have a strong following. I thought about getting
one, but after studying their specs. I found it wouldn't fit my bikes. I've
since been thru several configurations of a DIY belt drive. So far this is the one
that works best for me. The sheave(large pulley) is the rim of a 20" bike wheel
The small pulley is 2 spring washers with a spacer between on a 5/8" bolt
tooled to thread into the clutch bell. The engine(here covered) is mounted
to the channel of an old friction drive kit.
I've got a 40cc Tanaka on it. It'll do 30+, but I don't like to go that fast.
it cruises nicely at at 17 to 20 mph, gets around 120 mpg.(that's US gallons)
 

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thanks a lot mate, appreciate the pics :) yeah thats the one :) how did u mount the rim pullet to your wheel as i couldn't quite see? and i now have to work out a mounting plate to fit a 49cc pocket bike motor and work out gearing haha- me weak point :) and nice job on the small pulley thats sweet
 
It is a lot of work, and has to be very precisely done to work
properly. If the rim isn't precisely centered you get a nasty wobble
that can damage the clutch and rattle your teeth out.
If you send the pic to your pictures you can blow it up for
a better view.
What I did there is notch the rim to an exact depth matching the notches
to the spokes,(again I can't over emphasize the importance of being
centered) the depth of the notches is such that when placed on the
wheel there was just enough room to wedge a strip of alu 1/16" between
the spoke and the inside of the rim. these were then secured with
self tapping screws. You've no idea how many arrangements I went through
to arrive at a system that works as well as this one. Success at last!
Oh yes, It is the rim of a 20" bike wheel. This setup can handle a bit more
power than the cogged belt kits. I'm running a 2,2 hp Tanaka 40cc,
very reliable but costly Japanese engine.

Mounting a pullet is not as difficult as catching one:)
 
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hey iv seen a few people here with a rear mounted motor -around 30cc that drive the rear wheel by what almost looks like a smaller rim mounted onto there wheel and a belt driving them. just wondering if anyone can shed some light to where i can get one and what thy cost or if i can get a kit without an engine? i have seen a few kits but they are around 700$ thanks
Rawly is correct, GEBE is the best belt driven kit, I'm biased, I own three.It's expensive if you buy the whole thing, but you can buy it in parts if you have an engine and save bunches of $$.If you notice they RARELY come up for sale used, that's because once you have it you realize it's worth.I would suggest buying the sheave (pulley) and using it's notches as a guide for a 20"BMX wheel modification.Whizzers are roughly the same thing.What GEBE has over others is the notched-geardriven no slip belt.There was an Aussie ripoff called "Blackstar" though I don't know if they're still in business.Here's a decent pic of a whizzer-like belt-driven bike.
 

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I don't know what sort of engine that is, but it looks to be
geared about 8 to 1. That's way too high for most small engines.
I checked out the GEBE, but my stays being to narrow, I couldn't
use it. I found that a regular wedge pulley slipped if the pulley small enough
to give a good raitio. I solved that with the convex Belleville washers
that compress against the belt as it passes. It's still necessary for
the belt to be in contact with 50% of the pulley's circumference.
 
I don't know what sort of engine that is, but it looks to be
geared about 8 to 1. That's way too high for most small engines.
I checked out the GEBE, but my stays being to narrow, I couldn't
use it. I found that a regular wedge pulley slipped if the pulley small enough
to give a good raitio. I solved that with the convex Belleville washers
that compress against the belt as it passes. It's still necessary for
the belt to be in contact with 50% of the pulley's circumference.
I was just showing other builds.My stays were too narrow as well on my Bridgestone MB5, soooo I got out a 2X4 and a framing hammer and "adjusted" (didn't spread, just slightly flattened the sheave side stay) the side the pulley was on.If you ever think about GEBE, you can always redo the spacing on your axle washers and make it fit.
 
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I considered that & forcibly widening the stays. I even
replaced the quick release axle with a longer solid one.
I probably could have made a GEBE work, but where's
the challenge in that? Oh no, I had to go through a half
dozen builds to finally devise something that worked as well
or better spending half again more than a GEBE kit would
have cost. But, dammit, I did it my way, and it works!
 
Can't fault you one bit there, I must admit I've downed every pic you've put up including the handwritten diagram with the "bellville washers", as it's a great idea.The benefits of the actual GEBE is it takes out the guesswork, and it's LIGHTER than any other drive system I know of.Now if I could find someone to make me the engine bracket and the lower strap out of titanium I would have a drive system that weighed in at around 12-14 lbs total!!
 
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