Friction Drive system

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I thought I would start another thread on the Keystone bike, I would like this thread basically to be about the Friction Drive System along with theories and experiments.
Since I've never built one before this will probably be a trial and error thang.
Any advice and comments are welcomed.
There are friction drive systems available, basically those gas/electric add-ons that you mount on the rear wheel, some of them seem too work pretty good. In my case I need a drive system that uses pedal power and electric power working together but individually, if that makes sense lol.
I have several ideals and Cadcam drawings along with 3d object building tools all available to help build this thing.
I'm going to start with some drawings to set a general idea on the gears layout. also in building it I haven't taken too much thought about the gear ratio, basically I'm gonna look at it like an rc car set up.
Multi gears, with one gear turning in reverse, I did give that issue plenty of thought, it would of been weird pedalling backwards to go forward 😆.
Since electric motors turn counter clock wise, I'm able to chain it up direct to a freewheel that is attached to the friction wheel. The pedal part of it is a little more complicated, it will require three gears to turn the friction drive counter clock wise so the wheel will turn clockwise, looking at it from the right side of the bike.
To do that looking at the right side of the bike, I will need a top gear on the unit to be very strong, since it will take most of the torque while peddling, instead of the chain pulling on the rear of the friction gear, it will pull from the front, the third gear will be a simple chain tensioner, as illustrated in the pics. Note the friction gear will need two freewheels attached to its axle to work, I hope.
 

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I have a lot already started on this drive system, for those who don't know, this will be attached to a hubless bike.
 
Im thinking since the torque of running the freewheel s backwards the problem would be the freewheel spinning off the hub, so my thought would be flipping the hub over, where the chain and sprocket on the left side of the bike.

The pic shows the chain gear as it is now, on the right side.
 

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I should have it swapped over soon.

I kinda jumped over to a bike I bought at a motorcycle swap meet last summer, it's a pre 1959 western flyer, I'll do a thread on it soon.
 

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I like the design. Looks like a great deal of work to build it, though.
What I like best about friction drive is that you can easily change the final drive ratio by switching to a drive roller of a different diameter.
 
This is my thought, using a rear disc brake hub that will bolt into the side plates. The hub will be pressed to the tire, I'm thinking of using a spring or a adjuster.
The band brake will probably be the one I'll use. The hub won't hold two freewheel s, so I need to come up with an adapter. Thank God I have a friend with a lathe.
 

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This is a friction drive system for a gas engine, my design will be the same but different.
 

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Update of the drive system, I fabricated the two plates that are held together by the rear wheel mount and the rear disc brake hub, some how I need to set up two freewheel s on the left side for the motor and the pedals.
 

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Just using the hub as a friction wheel works but has no grabbing when wet or under load, I thought of many ways to get traction. So I came up with using spokes. It works great.
 

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The friction drive is partly connected, just need to make a tension pulley for the return. All I can say it works, the issue right now is the gear ratio, don't laugh, oh well go ahead and laugh but the result is for one complete rotation of the rear wheel the crank had to turn seven rotations.

Talk about low geared lol, the good news is it will be easy for the electric motor to rotate the rear wheel, definitely will find out soon enough.

As soon as I get the tension pulley on I'll have a small demo of it pedaling for its first time. Yeah!
 
The pedal part of the drive is functioning properly, with a 52 tooth ring gear brought it to 1 wheel rotation to 4 complete rotations of the pedal. Low enough to get this heavy tank rolling even up hill. This test was just to see if it have enough torque and grip the rear wheel, by adding drag to the rear wheel while pedaling the bike.

It took two jockey gears top and bottom and a tension pulley to make it work. It's time to see how it does on the street. Yeah! First ride coming soon
 

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I like the use of crossed spokes for passing debris through. I suspect they might not have enough bite when wet. What's your analysis regarding that?
 
I like the use of crossed spokes for passing debris through. I suspect they might not have enough bite when wet. What's your analysis regarding that?
It's hard to say at this point, the spokes seem to grab the nobbies on the tire like a gear. I know when the brakes are applied I can't spin the wheel by hand, I really tried to make it slip, it didn't slip at all. I'm not sure how it would act when wet.
 
If that's like the band brakes I use, they have no grab rolling backwards. I think the knobbies work well with your spoke drive.
 

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