Vehicle: Bicycle
Dual Chainsaw Starter Wheel   (+2, -1)  [vote for, against]
Bicycle with chainsaw starter type rope pulleys instead of chain and pedals.

I've recently been tinkering with chainsaw starters as bicycle motors. If pull-cord type chainsaw starter motors were attached to both sides of a free-wheeling drive wheel hub, then both chain and pedals could be eliminated. This is mainly a design for recumbent bicycles.

However, for conventional diamond frame bicycles, if the cords were attached to the upper torso from the back then a bicycle could be operated abdominally. In this arrangement, the rider would be using arm and abdominal strength, to pull the cords alternating from aerodynamic position to upright riding position repeatedly.

While experimenting with this type of mechanism, I was thinking about the advantages of using this type of motor over pedals. In conventional bicycles, in most cases when cycling shoes are not worn, the upward motion of the cyclist's legs are wasted. Using cords and pulleys, one leg extension could result in more revolutions than pedals. Furthermore, the bicycle could operate in differential ranges of motion, from short powerful bursts, to long full extensions.
-- rcarty, Aug 11 2013

operated abdominally [marked-fortagline]
-- zeno, Aug 11 2013


// chainsaw starters //

More correctly, "recoil starters".

There are static exercise machines like this.

Because of the arrangement of major muscle groups, human legs are much more effective in the push mode rather than the pull mode - rather like crocodiles having extremely powerful jaw muscles for biting, but only weak ones for opening the mouth.
-- 8th of 7, Aug 11 2013


Thought this might be the start of an idea about duelling bandsaws.
-- xenzag, Aug 11 2013


This is commercially available, I think it is marketed under the name "string bike".
-- pocmloc, Aug 11 2013


I've seen that before, but no that has pedals. This would just have a recoil motor . It might be possible to also have a derailleur system like on a conventional bicycle that changes the circumference of the winding spool .
-- rcarty, Aug 12 2013



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