Electric Bikes - Two electric motors one Bike

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Windecopower
06-09-08, 02:33 AM
Has any one tried putting two electric hub motors one on the front wheel and one on the rear of 200watts each with separate batteries and controllers?
tapholov
06-09-08, 08:20 AM
You actually don't need two batteries but two controllers are in order. I did this with 2 X 500W golden motors and the bike turned out to be very heavy. It was very interesting nevertheless since the front wheel by itself had a little trouble accelerating but went faster than the rear wheel by about 5km/h. It's like having two speeds. After a while, my way of doing things was to start with the rear wheel and hold it full open and manage my real speed with the left throttle connected to the front wheel (open terrain, out of corners,...). Opening both throttles at the start also made the bike accelerate faster but after a short while, one of the wheel takes over the other and you end up saving current (not bad). Low speed (25km/h) / high speed (30km/h). The batteries have to hold on: 36V 7AH weren't enough even for one wheel, NiHm 36V 13AH were good for 20 minutes, Lithium 36V 20AH (same weight) made things real good.
Does this help?
reptilian
06-09-08, 12:00 PM
you would need two throttles? Sounds like a complete waste of money to purchase another kit.
WJChris
06-09-08, 01:13 PM
also dont forget that the 2 motors are not perfectly in synch. One will be slower than the other causing inefficiencies that may negate the "benefit" of 2 motors.
I dont see a real reason to have 2 motors.
I dont see a real reason to have 2 motors.
2 wheel drive. Great for offroading.
2 wheel drive. Great for offroading.
For steep uphills I'd rather have all the power on the rear - the front wheel gets unweighted. There could be advantages to 2wheel drive though that you won't get from having a motorized front and pedal-powered rear.
For on-road, I'd definitely go with a stronger rear wheel motor over two weaker motors just to keep things simpler and maybe lighter. With a big hubmotor the amount of power you can put through one motor is really ridiculous - people are running some of those crystalytes at 5000 watts.
tapholov
06-11-08, 08:19 AM
I shouldn't have ridden that stormy night after a little too much partying but I ended-up on a football field, all wet grass and started doing doughnuts and leaning the bike as much as I could until the rear wheel lost traction. That's hard, because the Golden Motors are strong but not that much. What was amazing was using the front wheel to keep me going. Front wheel drive has its advantages. Yeah! two throttles, but a lot of fun. Also works quite well with upward trails that are full of roots. You don't get stuck. Takes a lot of power from the battery and some pedal assist is in order, but the moment when by-passers realise that you're going uphill and pedaling backyard is priceless.
H.
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