2 passenger Pedal/Electric Tadpole Trike

[jmygann]

A bike frame builder has proposed to build me a frame ....

"building a trike similar with potential for an electric motor and front suspension a reasonable figure would be $2500- $3000, with material cost around $1500."

My preference would be a side by side (sociable) trike

greenspeed currently makes a tandem tadpole that can be motorized..

http://www.greenspeed.com.au/gtt.html

a quad is more available but may not be a "bicycle"

http://www.lightfootcycles.com/microcar.php

to my knowledge no one markets a sociable

even the Stealth has gone to a tandem http://www.flickr.com/photos/10162336@N06/sets/72157620972785949/

suggestions on a 1000 watt motor .... hub or other wise

 

[spinningmagnets]

I hadn't seen that "stealth" before, very interesting. I hadn't thought about back-to-back seating for a tandem before. To create the optimum teardrop shape, this is a good solution. I'm in favor of two seats because I'd occasionally have a dog or some sacks of groceries in the second seat.

For a hub-motor, many choices would work for when you are alone, but if you have a person in the second seat on a hill, I'd go for a 5XXX. I haven't owned one, I'm just basing it on what I've read.

A while back someone posted a light motorcycle with a hubmotor and also a left-side drive. He used both motors when accellerating or pulling a hill. When just cruising, he only used the cylindrical motor on the LSD, which he felt was much more efficient than the hub. If you used this configuration, perhaps a freewheeling geared hub like the BMC, and a cheap cylindrical motor such as the Kollmorgen? Just a thought...

 

[waltinseattle]

re jmygann and "hub or otherwise?" I am a proponent of keeping things separated for ease of replacement and costs. Stereo amp and tuner, not integrated reciever. Laptop with external floppt, cd etc. One part breaks, then replace one part. I think this is relevant to wheels and motors. Of course it's a less eligant solution. Also I've gathered some negative comments about the mechanical life of hubmotors. And some defense too. I supose it depends on the way you hang them. Frankentrikes has to be VERY cautious and overbuild the axle mounting even though its fully supported on both sides. I'm thinking that there is a low power limit if one goes to car type axle with a steering driven wheel on each axle stub. Bike forks relieve this, but add weight- sprung weight perhaps. Although we know electrics have torque from 1 rpm, they do not have Efficiency as well. So there is good reason to do some gearing before hitting the rubber to pavement. This speaks for frame mountings. I've been going through my brain trying to see the best ways to integrate this concept to the pedal drive line. There is also the two separate drivetrain advantages.

 

[jmygann]

Perhaps this thread should be in the electric bicycle section , but maybe not.

some parameters ...

width .. 48" or less , widest part being the front wheels .. allows it to be loaded into a van or pickup

weight distribution .. at least 350 # of human weight plus ...batteries , motor etc.

position of cranks and legs to turning wheels

wheels - 20 in front, 24 in rear

suspension .. nice but adds to cost .. swing arm maybe taken from another cycle

steering ... over or under .. could even have rack and pinion

motor ...1000-3000watts ... at least 1000 continuous , bike laws state 750-1000 watts ( but who is checking)
hub motor- Marks , crystalyte
chain /belt drive - moulten(planet ryder) , etek , mars, RC

speed ... I would be satisfied with 40mph tops ... comfortable pedal cadence at 30 mph

http://www.recumbents.com/wisil/e-bent/TandemE-Trike.htm

 

[jmygann]

Looks like another college is doing the Pedal electric tadpole trike

Now to get side by side seating ...

http://www.youtube.com/watch?v=SCgihzmxoQ8