power only (no pedals) setup...?

Probably the wrong forum, but has anyone ever mounted an engine on a mountain bike, so that the sproket on the engine drives one of the 2 front sprokets on the bike that are normally used for high and low range selection?

My thought was to remove the pedals, hook it up in this fashion and add a set of foot pegs to the bike to rest my feet on, this would allow the rear gear selector to still be utilized increasing the range of speeds, and decrease the engine power needed (being that I"m 6'3 and 275lbs, this is somewhat important, and where I live there's alot of hills)

If this can be done, I am very intrested in how it was set up. I have a machinist available if I would have to make parts that's not a problem.
Here are a couple of pics of one way to do it

Note that the cranks have been removed and that
footpegs aren't shown


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yes, yes that is exactly what I had in mind. No additional chain to the rear hub, simple and clean. I was going to add a set of footpeg's right behind the front jackshaft to rest my feet on, and call it a day.

Does someone sell a kit to set one up like that or did you make it yourself? If you made it yourself, do you have a list of parts? How fast can it go, I'm not looking to have much over 30 mph but if it can go faster I'm not gonna complain :)

How reliable has it been, any major problems/regrets/things you would change? Only thing I can see I will do is make some type of guard, the sproket off the motor will be a little close to something......
I have no plans of doing any peddling, I'm looking for a way to put a 80 mpg way to get to work together that will go up a decent hill and go about 30 mph if possible.
Here's a few more pics of the other side


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Do you have any particulars about what looks like the extra reduction gear on the Mitsu. 43 cc engine ?,or is it just the auto clutch.What is the reduction to from that add-on gearbox to the front chainwheel.It looks to me that otherwise it would be impossible to get enough reduction from the engine to the rear wheel.You'r going to need at least 25 to get up hills.
One thing folks, when you take the pedals off, you go from being a bicycle with a motor into a motorcycle or moped, and the have to play with all the stuff that goes with it. Don't get me wrong, its a smart way to go, but know that the rules of the game change when you take the pedals off.
In Wisconsin this is one of the rules that lets you ride without all of the lights, mirrors, horn, turn signals, registration plates, insurance, etc.

Alan's right you avoid alot of problems by keeping the pedals,
The motor in the pics looks like it coiuld be slid futher up for pedal clearance to me. A larger frame even futher. Also there are wider pedal cranks,one guy just widened one.
There's Ghost0's happy time jackshaft http://www.motoredbikes.com/showthread.php?t=10772 , Cylcone, at least three types of rackmounts. The possiblilities are only limited by your imagination.
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