Pictures of 47-49cc pocket bike engine installs???

Chainreaction

Chainreaction

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I have used the search function and haven't found much. Just want to see how some other folks mounted them, ran the exhaust etc. It seems like a great little motor, maybe I'll find out differently since mine is on its way here. pocketbikeengine.jpg
 
I have been looking at those myself. Curious to see how it goes for you. My thoughts were to weld aluminum angle from the seat tube to the down or top tube to mount them depending how they lined up. I was thinking of those on a Skyhawk GT5 frame if I remember the name of the frame correctly.
 
49ccmountmeasurement.jpgPicture I found of bottom. Maybe I'll make some tube clamps if I cant find any decent ones, or maybe weld onto jackshaft bracket on one end, tube clamp on the other. I am concerned about the design look of the install somewhat. The way I like to do things like this is just move forward and get it done with design ideas kind of figured out, not worry about perfect or pretty too much. Then go back and build it right and pretty.
 
Thanks Ludwig. Well I guess I'll be teaching myself about the wily ways of the cag. I like the friction drives, maybe I'll do the wifes like that.
 
They don't fully engage drive until revving quite high, and give around 3hp. I'm probably going to have to add weights to the clutch shoes on mine so it takes off smoothly, at the same time as crippling the exhaust so it softens the delivery.
 
I have to admit that the CAG engines caught my interest right from the moment I first saw one. A front wheel drive setup would be very tempting, though I'd more than likely stick with the standard engine and stay away from the hot up kits. I learned my lesson back when I was in my early twenties when I tuned up a 1954 Austin A30 to an insane degree turning it into a genuine Mini Copper beater, - then had to spend every weekend working on it to maintain its state of tune or else fix something that had broken. Now that I'm older and wiser I'm quite content with off the shelf states of tune.
(not my one, mine was customised with a Wolseley grill and regularly fooled and confused folk at BMC dealerships)


I do wonder though if it would be possible to mount a CAG in a similar manner to this VAP3 from Ludwig's European Lightweight Motorised Bicycle thread.
vap3_2.jpg
 
I think these cags are nearly 7 inches wide, plus you have the pull start on the right side which I suppose could be removed. Still might be a bit wide for mounting on the side of the wheel.
 
Trying to keep things on the cheap. I think I can probably spread the crank and inch on each side to clear the motor. I mounted the drive #35 60T drive sprocket on the inside of the crank gears, made some little spacers to put keep them separate.

P1010006.JPGP1010011.JPG
 
I've said this before elsewhere, much of the engine and transmission could be placed away from the crankshaft ends. If the clutch and the pull start come off, that takes nearly half the width out. If a KO/China Girl style gear and manual clutch were then adopted, it wouldn't add much back in, and it would remove the need for a separate starter.

The next question is whether or not removing the fan is going to kill the engine. Provided it is driven slowly, I don't think so, but somebody would have to make one like that and report back. Probably, but not guaranteed, from the roadside.
 
The orange bike here is somebody else's, but it shows how neatly you can build a Cag in. The second pic was part of my creative staring, and the unit will fit in the dip in a ladies frame bike as well.

I'm going rack mount as it's the simplest way, although we've managed to complicate it a bit by making discreet bracketry.
 

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You have me thinking of building a CAG based bike now. I had a bad experience with the performance version so will go with the base stock version. Have seen plenty of kids beating them pretty hard on the mini-motos.
Have an mens cruiser frame that has plenty of room for mounting. Using the reduction gear box(chain actually) its a simple matter to add a rag joint sprocket and idler via the CG system. These engines/gearboxes are $75 shipped. Cheap enough to play with.
 
I made the frame for my wifes bike too, kind of a stretch crank forward design with low step through. After giving it good looking I may mount the engine on the downtube from the steering stem, still have plenty of room to step through. I can't seem to make myself like the idea of direct drive single speed though I love the idea of the simplicity of rear rack mount.
Melyndabike.jpg
Yeah these motors are cheap, next time I order I'll get 3-4 of them. I have a feeling once I get mine built I'll have people wanting one.
 
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My friend went over the top attaching his sprocket to the disc rotor, I only used 4 bolts.
 

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Dang I like that look, if only I could have but two gears I would be in love. I wonder if anyone has tried to put a gear box in the gearbox?

That is a little over the top, all dem bolts.
 
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There are CVT units you can get, some of the advertisers here sell them.

My bike's getting a simple silencer box instead of the expansion pipe, and the supports will be neater as we have the original JC put together to look at and think about.
 

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I have looked at the cvt's, I wonder how much power they suck up at the rpm ranges of these 2 cycles. When I was a kid I had a Tote Goat, like a mini bike except more geared down, had a CVT. The CVT was awesome but with a low speed briggs didn't suck up much power.
 
They don't take an absurd amount of energy out, and if you can spend a couple of hours on a dyno, then deciding how many rollers of what weight go with what weights of clutch shoe springs and what rear cone tension spring pays dividends. I know scooter racers, and much success is down to matching transmissions to circuits/usage.

There is one sneaky trick I never got the hang of. If you want a low ratio coming out of a corner, hold the back brake on a bit, and keep the throttle open. The transmission then"changes down", and you launch like a rocket.

In my soul and reflexes, it was too barbaric, but it works.
 
Looks like you can get a cvt on ebay for $100, not bad. On my bike just going to crank for cassette gearing. I am going with #25 chain from engine to jackshaft, the chain came in the mail, I had no idea it was so stinking small, they really use this on pocket bikes? I kind of like the #35 chain. As of now I am using 3 chain sizes, #25, #35 from jackshaft to crank and then of course regular bike chain.
 
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