I'm in the process of putting together a rather large bike around a Micargi Triplet Tandem, a trail-a-bike and a double child trailer.
The project is part of a crazy dream of mine where my entire family of 6 is going to ride across Iowa in RAGBRAI 2010. (450-500miles over 7 days)
I want to use a bike motor in a very different way than most people. I plan on not using it very often, and mainly only if the kids tire out on a big hill or during the last portion of the day's ride. (A $200 motor is a great insurance plan against a family rebellion) Also, in Iowa, I have to keep the maximum attainable top speed on level ground to < 25Mph to operate under the slow moving vehicle laws. (Since I will carry more than 1 person, I will fall into slow moving vehicle laws, rather than bicycle or moped laws.)
Additionally, long term reliability is not a concern. The whole thing will probably not be used much after the big RAGBRAI event is successfully completed. For this reason, I'd prefer to go as cheap as reasonable since this is a one shot wonder vehicle.
So, the questions for this thread are:
1) Are there any particular engines I should look into knowing that it will be pushing a 600# vehicle weight (Bike + 6 riders)?
2) Does anyone know the red-line RPMs on these little bike motors? I might need that to document that the engine and gearing can never go past 25Mph in normal operation. (I'd prefer a cruising speed of 16-20mph)
3) How big of a sprocket should I be using for something this heavy? (From a pulling standpoint? I realize the max speed requirement might force me to a higher gear than pulling requirements)
4) Is there anything specific I need to consider if I want to spend 80-90% of the time pedaling with the motor off?
The project is part of a crazy dream of mine where my entire family of 6 is going to ride across Iowa in RAGBRAI 2010. (450-500miles over 7 days)
I want to use a bike motor in a very different way than most people. I plan on not using it very often, and mainly only if the kids tire out on a big hill or during the last portion of the day's ride. (A $200 motor is a great insurance plan against a family rebellion) Also, in Iowa, I have to keep the maximum attainable top speed on level ground to < 25Mph to operate under the slow moving vehicle laws. (Since I will carry more than 1 person, I will fall into slow moving vehicle laws, rather than bicycle or moped laws.)
Additionally, long term reliability is not a concern. The whole thing will probably not be used much after the big RAGBRAI event is successfully completed. For this reason, I'd prefer to go as cheap as reasonable since this is a one shot wonder vehicle.
So, the questions for this thread are:
1) Are there any particular engines I should look into knowing that it will be pushing a 600# vehicle weight (Bike + 6 riders)?
2) Does anyone know the red-line RPMs on these little bike motors? I might need that to document that the engine and gearing can never go past 25Mph in normal operation. (I'd prefer a cruising speed of 16-20mph)
3) How big of a sprocket should I be using for something this heavy? (From a pulling standpoint? I realize the max speed requirement might force me to a higher gear than pulling requirements)
4) Is there anything specific I need to consider if I want to spend 80-90% of the time pedaling with the motor off?