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Old 09-14-2010, 02:04 PM
peterarev peterarev is offline
Motorized Bicycle Newbie
Join Date: Sep 2010
Location: Tucson, AZ
Posts: 4
Default Re: Golden Motor electric owner from Tucson, AZ

I think there is a HUGE difference between front and rear wheel drive. I haven't ridden a rear wheel drive electric bike, but have ridden several sports bikes throughout my life and owned several motorcycles. There's one thing that distinguishes these from a front wheel drive: the weight and "moment" or torque of the power is in the favor of traction as the front wheel rises and more weight transfers to the drive wheel. On a front wheel drive it is just the opposite, the weight tends to transfer off the drive wheel or at least not transfer to it. Although there is no tendency to wheelie, quick starts are virtually impossible as the wheel spins out and traction does not catch up until moderate speed is reached. Even at cruising speed, small bumps in the road will cause the drive wheel to jump and spin and then skid when landing again interrupting power to the road momentarily. In addition, all this causes increased wear on the tire.

On the plus side, there are some convenient and beneficial effects of front wheel drive. When standing still you can turn the wheel as far as it will go and spin the bike around to face a new direction. This ability rapidly diminishes as the gyroscopic stability of the spinning wheel increases with speed, but it can be helpful in many very low speed riding situations. At higher speeds there is a bit of a stabilizing "power steering" effect since the drive wheel always pulls in the direction of power. There is also an advantage in certain surface conditions such as sand or pea gravel. If you still have your pedals and gearing you essentially have a two wheel drive bike, although coordinating the two can be a bit tricky. I have a lever throttle instead of a twist grip so it's mostly just a matter of charging through quickly under power and pedal with the cruise control set. Normally, the front wheel bogs down in a soft or yeilding surface, but with power it climbs out of it providing you have enough momentum and/or rear wheel power. Also, as I've mentioned earlier is that the weight of the installation is split over the front and back. My battery pack is on a rack over the rear wheel. If it were all on the rear, I'd be really stressing my rear spokes and tire and taking even more control weight off the front wheel especially with a full load of cargo in my rear baskets and on top of the battery (I routinely carry a 30-pack of beer home from the store this way in addition to a large bag I always carry and the other basket full of other items.) Finally, the motor acts as a front brake by turning into a generator when the either of the brake levers is applied. I don't even have brake cables attached as my cruiser has a coaster brake and didn't come equipped with front brakes. The "regenerative braking" is very smooth and "reverse progressive". At high speeds the braking force engages the most and as the bike slows it gradually diminishes to nothing. It doesn't cause the dangerous break in front wheel traction on slippery surfaces that a more positive brake does. (The electrical recharge advantage of the brake is minimal and would only come into play if you decended from a VERY long and steep slope. It is virtually impossible to pedal against the brake on a level or even moderate downward grade. It's only intended use is for braking.)

A front wheel installation is far from ideal, but the reason I did it was to preserve my 7-speed internal hub in the rear. Two hubs simply can't occupy the same space. I'm not a performance rider and am simply happy to have electric assist at all. The fact that I can ride even if I don't feel like pedalling significantly makes my bike a very workable primary transport. My truck sits idle the vast majority of the time and it almost seems a sin to pay the yearly insurance bill which is many times more than what I pay for gas even at 8 miles/gallon.

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