Here is my concept: Take a road bike and put the largest front sprocket as possible in the front. Take away all other front gears. In the rear cluster put the smallest to highest ratio. 

The idea here is POWER. To work it. No messing around and get going. Skip all the pansy front shifting and use POWER. Pulling on the handle bars and pumping the legs for a maximum work out. And with the maximum speed. 
Secret is Being Positive
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