how about we all

deacon

minor bike philosopher
Jan 15, 2008
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conspire to build my next bike.

Since I don't have a frame but maybe have an engine on the way we can all work along on what to do next. I'm not in any hurry except to make sure the motor runs when it arrives next week. More ebay junk I'm sure.

So first decision is the bike frame. Since the motor is 25cc I'm thinking small light bike frame. I would really like to have a 24" sissy mountain bike or road bike. With that I would have all of little the parts to build a nice one.

If I convert to a coaster rear wheel, then I have one brake lever and cable to use for something else. I also have the shifter to use as a throttle if i go that way. If I run across a 24" road bike I can do the same thing. The rear wheel I can replace with a coaster for the ease of operation and the wider tire is more stable.

Now what would you look for in a frame on a 25cc engine friction drive bike?
 
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jasonh

New Member
Jun 23, 2008
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Deacon I think you should take your little weedeater motor and mount it in front of the crank below the tube, kind of like factory mopeds are. Instead of a friction drive, make it a chain drive and use the rear derailleur to shift through the gears, kind of like Pablo's kit.

But this way you'd be able to take real advantage of that small motor. Only real issue is either finding a front freewheel crank or figuring out what to do about the pedals spinning...

just a thought..
 

deacon

minor bike philosopher
Jan 15, 2008
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north carolina
I'm thinking you would have to have a clutch for that. I doubt that the little flimsy clutch that comes with the engine would ever do. I just don't know enough to even think about all that stuff lol.....

I would need an engineer to figure out the torque and gear ratio. I have seen those things on utube that run direct to the rear sprocket. It might be possible to freeze the pedals in place take off the chain ring and run the bike chain from one small front sprocket on the engine. Probably would play **** changing gears lol. But it is a thought. If you could gear it down a mountain bike, you might could just push it off to get up enough momentum to engage the engine. That really is deserving of more thought
 
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deacon

minor bike philosopher
Jan 15, 2008
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north carolina
It looks like I'm going to mount the friction drive on the front wheel. Some one got my curiosity up about a powered tricycle.
 

deacon

minor bike philosopher
Jan 15, 2008
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north carolina
I saw the picture of a bike on another thread and my mind is raceing. It had the drive sprocket on the FRONT wheel. That would solve all the problems.

Mount the small 25cc helper engine on the top of the front wheel with the counter clockwise drive shaft facing to the left. That would make it pull in the right direction if you were using a sprocket on the wheel.

If the motor was mounted on top of the tire there would be no balance issues. The drive system I have now might adapt itself to mounting a sprocket onto a short pipe nipple with a couple of pipe nuts to hold it in place.

The engine would still stop and start with the movement of the wheel so you would not need a clutch at all. It might provide better power since there would be less loss of energy in the transfer.

I think I have decided on the next build. It seems to be an experiment worth making.
 
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deacon

minor bike philosopher
Jan 15, 2008
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north carolina
Having been on tv makes me a target for everyone... The guys at the bike shop saw the show and were nice about it. I didn't get a discount but they were nice.

As I was test riding my ww bike through the hood I got flagged down. I stopped because the guy had a yard sale last week and had a bike I sorta looked at. this time he had one all to pieces he wanted to sell me. The brake levers and the tires were worth the asking price so our choices just got smaller. If you have any ideas let me know.


So what we gonna do with this one. I'm thinking single speed. Cut the chain and make it fit what ever is the straightest run sprockets. Then use the rear brake as a brake. The front to work the suicide clutch.. the shifter as the throttle all for the 25cc. this one has the two front chain rings so I'm going to freeze the small one I think.

Change the front wheel for a 24" with the 25cc sitting on it. Gonna be suicide for sure with no front brakes and lever brakes in the rear.

Now please better ideas. I am not going to start this for a few days.
 
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jasonh

New Member
Jun 23, 2008
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Looks like a good subject to start on. I'd just try to get that motor as close to the frame as possible. I don't think it'd be good to have it kinda hanging out over the front.
 

deacon

minor bike philosopher
Jan 15, 2008
8,117
3
0
north carolina
I was kinda thinking that but for for the controls. Of course I'm not sure how it would work out that is a lot of bike for a 25cc to pull around. I expect it would be a pedal most of the time kind of bike, even with the engine on. My town has hills not too many huge ones but a lot of pretty good ones. It's called HIgh Point for a reason,