A new Geared Experiment idea maybe?

Some ideas from GT bike

Frame mounted hub:
Check the GT dowhill bike frame mounted internal hub set up. One comment on this set up is that the hub is not touching the frame on the encased tubular section around it. That is done just for looks. The hub is suspended from the axel. The output sprocket from the hub is mounted where the disc would go, on the left side.

In our case with an engine with an output sprocket on the left side, we would have to mount the Staton double gear sprocket on the right side of the hub. The engine would still need a jack shaft to bring the power to the right side and work on some ratio reduction.
But the pedals would just fit exactly like on the GT.
An ideal candidate for the hub would be the either the dual drive hub(3gears 187% change) from Sram. It would require a fixgear/bmx adaptor(acepts BMX style feewheels) from Sheldon Brown's web page: http://sheldonbrown.com/harris/fixed-hubs.html
Another one to check would be the new Sram i-motion9-disc(to mount the output sprocket instead of the disc) (9gears 340% change) (for sale next year).
Not cheap, not that complicated, but still needs a jackshaft and enough room on the frame for al this to work
GT internal hub on frame right side view.jpg

GT internal hub on frame left side view.jpg

GT internal hub on frame bike.jpg

Staton freewheel and fixed sprocket for left side.jpg

fixedk7(From Sheldon Browns page).jpg
 
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Maybe I did not explain the above good enough. The idea is to have only one chain from the frame to the wheel. All the double chains and sprockets and the internal hub and engine work on the frame.

This set up is clean an opens the door for REAR SUSPENSION.

A big issue when off-road riding.
You can't have rear suspension with frame mounted engine and the double chain to the wheel set up currently in use.
So this might be it, to hit some dirt roads with the benefit of full rear suspension and gears.
 
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That is one cool system. I hope that Ghost0 sees this post, something like this would be perfect for his custom offroad bike.
 
Internal gear jacshaft

I've done this and it works but you have to have a freewheel hub for the jack shaft. If you had that you'd need a pull start on you engine. I'm not sure how long the internals of the hub would hold up to the forces of the motor. I used a Shimano on this bike. Sturmey Archer makes a very inexpensive 3 speed freewheel hub...I think it's about $60 with a shifter. If you use a disc compatible rear hub you could just bolt a 44t where the rotor would be bolted on. I've done that too and it works great!

Dan

Great bike!

Why do you flip the hub? Isn't the sprocket usually on the right side? Or is the photo flipped? I've never touched one of these hubs - do they freewheel? If they do, and you flip them, wouldn' they freewheel when you pedal?

thanks
 
Product tester

Funny you should ask about the left side geared hub option. My dad and I are in the process of designing that very item. We should have prototypes by the beginning of the year. We may even ask of few of the members to try out a few of the prototypes to get some feedback. I will keep all up to date as the project progresses.

Hello Ghost,
If you would like a bike to try it on, mine is available, I would be honored to test a left side geared hub. I can provide detailed feedback to the site with pictures and video.
....Thanks, quarkdude:D
 
Product tester

Actually this is what the project has turned into.
http://www.motoredbikes.com/showthread.php?t=8978&page=6
We still may be looking for a few guinea pigs once we get production parts. Will keep you informed.

Hello Ghost,

I looked at the thread link you provided and looked at the pictures, Wow! I like it a lot. When you get it to the level you like it, I am ready to start wrenching on my bike and installing the product for testing and Video feedback.:D:D:D Let me know when you are ready, I'm ready now. That is soo cool what you guys have come up with.
........Thanks a bunch, quarkdude
 
10.000km done with 3 speed gearbox/hub

see my new thread in 'introduce yourself' on 3 speed gearbox/hub
 
It still takes an overall reduction of 15-20 (depending on engine size) to the rear wheel.The SA hub is 075-1-1.33.So two 4:1 chain reductions would be reqd.I don't know what the smallest sprocket is that can be mounted on the hub body prob 20t +..Also the input sprocket on the hub would have to be substantal.It could work in principle with an internal 4:1 reduction in the engine, if the engine output was on the right side.The hub would be running much faster than normal although at reduced torque, the gears might wear more,the old SA hubs I am familiar with needed oil,mainly for the gears.
 
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