Anybody else running an electric front hub?

I used to have a front drum brake that was made in Norway. It had a torque arm attached with an end that looked like an open end wrench. The U shaped end of the torque arm fit into a pin brazed on the inside of the corresponding fork blade. That kept the hub brake backing plate from rotating, and made it really easy to remove the wheel. No clamps to undo, just the axle nuts.
Another ideas, what if you made the dropout slot narrower to tightly fit the flats on the axle or made retainers which locked the axle in the dropout. On planetary multigear rear hubs the axle shouldn't rotate either, they use similar methods to prevent axle rotation in the dropouts.
 
torque arm

I like the pin idea. For now, the hose clamp is working well, but I might switch over to something like that later. My primary concern is keeping the torque arm attached to the axle. As far as the dropouts being tight enough to hold the axle, that was how it started out. The problem was that this design depended entirely on the dropouts to hold the axle in place. That's too much torque. Even my steel dropouts got bent open wide enough to let the axle spin.
 
I took apart my brushless hub motor and controller

OK, I finally decided to take this thing apart and see if I could find the problem. Looks pretty solid in there. Getting it apart was a challenge. The bearings are pressed in pretty tight. I actually pryed it open bit by bit using the prying end of a claw tooth hammer and placing washers under the edge as I moved the hammer around the outside of the hub. Eventually one of the covers popped off and it got easier after that. Reassembly requires that you not get your fingers anywhere in between the hub and the cover as you put the windings back in. This thing snaps together with enough force to break a finger and probably keep it in there, so watch out if you try this at home, kids.

Taking the side covers off the controller just revealed that the ENTIRE CASE had been filled with some sort of rubbery glue. There was no way for me to look at the circuit board and be able to tell if anything had burnt up. That was a waste of time.

Since my hub wires were pretty much trashed where they go into the axle, I cut the entire harness to remove the section with the torn insulation and bare wires, then spliced it back into the wiring inside the hub by soldering them together. Satisfied that my hub wiring is solid, I put everything back together and still had the same problem.

I know that my motor turning rough and only moving 7mph will be either the motor or the controller. I ruled out the wiring harness at the axle.

The next step is to disconnect the battery and short the three big wires from the motor harness and spin the wheel (short them to each other, two at a time). If the wheel moves a little bumpy, that means the entire cicuit from the wire all the way through the motor windings is good. The motor should generate a little power and send it back through the shorted wires to give it a little bump as it rolls. If any wire doesn't cause the bumpiness when shorted, that's the problem.

I'm not sure about the Hall sensors. This is where I think the problem is, but it could be at the motor or at the controller. There are spots where the wheel stops where it will not start again until I move it a little.
 
Do you have electrical specs for all the components in this system? A multimeter would be a useful tool to have in this situation. I spend a lot of time away from grid electricity. This post has got me thinking about making a hybrid. Use an electric hub motor, batteries and a little gas motor running little permanent magnet motor as a generator to constantly charge the batteries, plus regenerative braking as a charging source.
 
specs

No, I don't have any specs. I'm just troubleshooting based on basic electronic theory. I did actually isolate the problem as being a bad hall sensor, but I can't seem to get info on how to abtain a replacement. Hopefully, I will hear back from the manufacturer soon. If I had the specs, I could just order a new sensor based on the requirements, but instead I am dependent on the factory either sending me new sensors or telling me where to find them. All I have to go by right now is just the number "41f 634" printed on the sensor.

The hybrid idea sounds really cool. You could plug it in to charge it and if you were lucky, you would never have to run the motor. If you run out of battery, on goes the motor and now your batteries are recharging. That would be great.
 
Blaze, since you have both an electric and an "infernal" combustion engine powered bike, I interested in your opinion about and comparisons of the two methods of propulsion. any comments?
 
electric / gas comparison

psuggmog said:
Blaze, since you have both an electric and an "infernal" combustion engine powered bike, I interested in your opinion about and comparisons of the two methods of propulsion. any comments?

If I had to choose just one, it would probably be the gas powered bike. When you really look at it, it's just the same reasons nobody drives electric cars.

I would much rather use electric power, but it's just not ready yet. My electric bike is so quiet you can hardly hear it at all, and it runs very smoothly. There just isn't any vibration from the motor. I love it. And I love not burning any gas.

I haven't had my electric long, but once I get everything ironed out, I expect it to be pretty maintenance free, except for the batteries. The gas bikes vibrate everything loose, and tend to need adjusted every now and then. Nothing major, but if you have a gas bike, you had better know how to fix it.

Electric bikes are always clean. My gas bike usually has burnt 2-stroke oil all over the back wheel and frame. Cleaning that burnt oil off sucks.

The biggest problem with electric is batteries. Sealed lead acid batteries are very heavy. 55 pounds of batteries (48v 17Ah) will only get me about 21 miles, and then I have to recharge them for about 10 hours. Not very practical for scootering around all afternoon with friends. Sometimes we have put 40 miles or so on our gas bikes. Only being able to go 21 miles per charge is a pretty bad limitation. After that you are pedalling a bike with about 100 pounds of dead weight on it in the form of batteries, controller, and electric motor. Not fun.

A gas bike with less than 1/2 gallon of gas can outlast all but the most expensive electric bikes, and the gas bike will have full power the entire time. 1/2 gallon of gas weighs about 3 1/2 pounds, compared to 55 pounds of batteries to power the electric. The gas bike will climb any hill with ease and it will be capable of going full speed all day long. If you should need more gas that day, which is unlikely, you can refuel in a minute or two. The range is practically unlimited. The cost of gas is irrelevant when you are only burning a couple dollars worth for the entire day.

The advertised top speed of my electric motor was 24mph. Bulls**t. Mine goes 18mph when the batteries are fresh, and slows to around 15mph before they go dead. Most gas bike are in the 20-30 mph range. Like real, actual 20-30 mph.

NiMH, Li-Ion, Li-Po, and newer batteries are too expensive to be practical. You can build an entire new gas bike for about $300 ($180 for the motor and shipping, $120 for a new bike to put it on), while a 48v 13Ah NiMh battery pack will cost $460, and will eventually need replaced anyway. Bear in mind, that's only 13Ah, would give me less than 20 miles. If I was willing to spend more money, I could build an electric bike with Li-Po cells and it would be light and have awesome range and everything; or, for the same amount of money, I could build an entire fleet of gas bikes, all of which would perform better than the electric.

So the bottom line is that I would rather have an electric, but they aren't good enough to replace gas yet. I will be keeping my gas bike, thank you. It's the same as electric cars.

I want an electric that goes as fast as gas, weighs the same as gas, and drives as far as gas. Until then, electric will not be as good. It will be fun, just not as useful.
 
I've been on the fence between a gas and electric power for about a month now and was leaning toward electric until I read the post by Blaze.
He presented a very good and well thought out comparison between gas and electric and helped me make up my mind.
I just looked at a Giant Suede E that costs $1000 and really like it for my needs until I found out from a user group over at Yahoo that a replacement NiMH battery would cost $500 or 1/2 half the purchase price of the bike. Even generic batteries for this model are kinda pricey.
So blaze, I appreciate your comparison and I totally agree with you that electrics are great but the technology is not quite there yet. I'll go with gas as my primary rider but may get into a less expensive electric just for fun.
 
blaze, l have the black electric hub on my trike and l'm 140lb and my trike will do 20+ with an extra battery(4 total 12v 12ah). l think that electric is great, they also make different controllers to get your speed up but loose range. the electric hub is going to be changing, for the better.
l think that electric is good for older people who want to have a casual ride in town, and l think that gas is good for all us hot rods who want to go balls out. l have a gas and an electric(spookytooth), and im more than pleased with both.
 
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