Author Topic: Axle Issue On Rear Wheel Motor?  (Read 16311 times)

Offline Dave

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Axle Issue On Rear Wheel Motor?
« on: June 04, 2007, 09:36:12 PM »
Hey all:

I'm considering the purchase of one of the Golden kits, and have not settled on whether to go with the front or rear kit. I like the idea of the rear wheel kit as the bike carriers I have are of the fork-mount variety; a motor on the front wheel would make it necessary to get a different carrier for those times I need to transport the bike.

On the other hand, I'm kind of a big guy (6'2", 240lbs) and have had problems in the past with bending rear axles on mountain bikes (haven't had the same problem with my road bike, probably because of better weight distribution and different riding styles/road hazards.) I finally resorted to a solid rear axle to get around that problem.

I'm planning on putting the motor on a mountain bike, but the question is whether there is any likelihood of the axle bending on the rear wheel kit. And if it does bend, how is the axle attached to the hub, and how difficult is it to replace? I worked in a bike shop through my college years, so the job itself doesn't scare me, but it's still something I'd rather avoid.

Any big guys have any real-world experience with the rear wheel, and whether my hesitation is warranted?

Offline myelectricbike

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Re: Axle Issue On Rear Wheel Motor?
« Reply #1 on: June 05, 2007, 04:43:59 PM »
The rear wheel axles require the same spacing of a Tandem bike and there is a dimensional drawing link on the homepage.

Both front and rear axles are press fit into the stator so bending is unlikely to occur unless the wheel gets hit by a car.  Rear axles are 1/2 inch diameter. For a bike I'd stay with the motor in front and use a rear wheel motor only to build an e-tadpole. However, the homepage also has a picture of a Giant rear wheel conversion if you can afford the high cost of low weight batteries.
« Last Edit: June 06, 2007, 08:44:27 AM by myelectricbike »

Offline Dave

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Re: Axle Issue On Rear Wheel Motor?
« Reply #2 on: June 06, 2007, 07:09:54 PM »
The rear wheel axles require the same spacing of a Tandem bike and there is a dimensional drawing link on the homepage.

Both front and rear axles are press fit into the stator so bending is unlikely to occur unless the wheel gets hit by a car.  Rear axles are 1/2 inch diameter. For a bike I'd stay with the motor in front and use a rear wheel motor only to build an e-tadpole. However, the homepage also has a picture of a Giant rear wheel conversion if you can afford the high cost of low weight batteries.

Um, what's an "e-tadpole"?

Offline OneEye

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Re: Axle Issue On Rear Wheel Motor?
« Reply #3 on: June 07, 2007, 03:42:04 PM »
A tadpole is a 3-wheel recumbent tricycle with two wheels up front and one wheel in back.  I think a recumbent trike with 2 in back and one up front is called a delta.  There are also two-wheel recumbent bicycles.

An e-tadpole is a tadpole recumbent with an electric motor, usually on the rear wheel.

If you put a disconnect plug in the wiring on the front fork, you can make a front wheel hub motor quick disconnect to use your standard carrier.  Someone else posted they did this to their bike, although he compared the appearance of his effort to a Frankenstein monster.
« Last Edit: June 07, 2007, 03:46:03 PM by OneEye »

Offline doc

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Re: Axle Issue On Rear Wheel Motor?
« Reply #4 on: June 20, 2007, 02:55:24 AM »
I'm a big rider 6'3" 230lbs. I purchased the front wheel brushless 36 volt version from golden motors and have been totally pleased with the performance.  I've put on 1200 miles and the only problem I have had is starting too fast and popping a 20 amp fuse.  I've done this about 5 times.  I carry extras with me at all times.  I would think for weight distribution that having the motor in the front makes more sense.  I have a 20 year old Schwinn mountain bike with the Bell flat fighter tires on it.  I haven't had a flat yet and have ridden over some stuff fearlessly that I would never do on my Trek road bike. I commute 10 miles stretches 4 times a day with 1 to 3 hour recharge times.  At night is the only time I get to fully recharge my lead acid extended battery pack.  My son has used my bike a bit and he only weighs 120lbs.  He can really fly on that bike 22- 24 mph. I average 18-20mph.  I have found I'm much more willing to ride a bike to work when it is electric and I don't sweat as much! :D   

29a

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Re: Axle Issue On Rear Wheel Motor?
« Reply #5 on: June 21, 2007, 12:15:47 PM »
I would go with front allway's,
The rear wheel recieves far more damage than the front even in a normal bike and you don't want to damage the wheel with the hub motor in.
Allso the rear wheel drives tend to need constant spoke adjustment because of the torque's involved

Offline kickabear

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Re: Axle Issue On Rear Wheel Motor?
« Reply #6 on: June 21, 2007, 03:29:28 PM »
I'm a big rider 6'3" 230lbs.  [...]  At night is the only time I get to fully recharge my lead acid extended battery pack. 

Dave,

Can you tell me what your battery configuration is?  I'm about 220, so I'm looking for something which can haul my fat butt around.  Also, what is your max range?  What is your typical terrain? 

Thanks!
John