Full suspension gas tank frame design concept.

I have been working on drawing a concept of what I would like to make reality in a perfect bike frame.
I went through around 30 different designs before i settled on this one. When drawing i set my goals to make the perfect sleek looking functional and buildable frame that had all the features missing in my last build. Features that are hard to come by in a motorized bicycle frame.
I wanted a gas tank built into a frame with rear suspension. It needed to be able to support a 7 speed rear derailleur, disc brakes, and a 3.5" or less wheel.
I also wanted the layback seat post built in and a built in bearing for the shift kit.
This is what I came up with.
86108

I only quickly painted it to show how cool it could look.
86109


I put this out in the world hoping that you can offer feedback. Hoping that no one will steal it and make millions while I still sit broke.
 
Wheel goes up will cause chain slack, so you are going to run 2 chains? One to bottom bracket jack shaft? You will also have to offset your motor to clear 3" tire.........Curt
 
Wheel goes up will cause chain slack, so you are going to run 2 chains? One to bottom bracket jack shaft? You will also have to offset your motor to clear 3" tire.........Curt

I dont get it? if I the crank rotates with the whole rear of the bike why would it create slack? how do other bikes do it? they all attach to the crank.
Also again It will be jack shafted. If I want there to be a second chain I will draw it.
 
If you are going to run 2 chains, with jack shaft in bottom bracket there will be no chain slack? .........Curt
 
That will work, the closer the pivot to bottom bracket the better, like a mountain bike pivot..........Would also work with your early design, just change the spring angle like this one.........Curt
 
View attachment 86124This is the chain path Im thinking. Also as i said earlier but didn't draw it until now, there will be a press in bearing built into the frame so i dont need to buy a kit just the hd freewheel.
Not good sorry. Pivot in the wrong place for a motor build, frame not big enough for a 4-stroke. Spend some dozen hours reading about search terms as anti-squat, chain efficiency, motorcycle cg/ handling dynamics, and predator 212 engine dimensions.

Also that swingarm would fold up on a harden enough impact.
 
Not good sorry. Pivot in the wrong place for a motor build, frame not big enough for a 4-stroke. Spend some dozen hours reading about search terms as anti-squat, chain efficiency, motorcycle cg/ handling dynamics, and predator 212 engine dimensions.

Also that swingarm would fold up on a harden enough impact.
Don't listen to this guy. Your chain path looks fine. If everybody always built in what is tried and true we would never have anything new. The engine in the drawing is obviously a China girl. How can you know the strength of anything without knowing the thickness of the tubes and the diameters?
 
Don't listen to this guy. Your chain path looks fine. If everybody always built in what is tried and true we would never have anything new. The engine in the drawing is obviously a China girl. How can you know the strength of anything without knowing the thickness of the tubes and the diameters?
Thanks for your support. I havent decided on the frame material yet let alone the rest of the specs. I wonder if carbon fiber would hold up?

Not good sorry. Pivot in the wrong place for a motor build, frame not big enough for a 4-stroke. Spend some dozen hours reading about search terms as anti-squat, chain efficiency, motorcycle cg/ handling dynamics, and predator 212 engine dimensions.

Also that swingarm would fold up on a harden enough impact.
I don't like 4 strokes, I like the looks feel and upgradability of the 2 stroke, however if you want to kill yourself with the extreme power and torque of a 212cc engine, or go to jail for street riding then feel free to remove the seat support bar i only put it there to be able to mount the engine i wanted, and have a place for nos canister, and electrics.

Also if I wanted motorcycle handling I would design this completely different. say a 2 rail frame not one, and a rear tail structure and external gas tank. Thanks for the feedback though, Now i want to draw a motorcycle frame.
 
Don’t use a shift kit, ss 42mph get a good distance between cone and head, torque pipe. For it to be popular gotta size it for all common sizes.

I was thinking of plasma cut weld on kits for cruiser frames.
 
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I don’t think you guys quite understand the urgency of frame size and safety if you plan on selling them. You may have never intended it but some idiot who puts too much power on it with some questionable mounts can tear it up. People will modify bottom tubes to fit motors so best to take control and make the frame big enough so they don’t have to cut it.
 
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