Counter Clockwise Motor

[trikeman]

TheDude posted a good website with deals on scooter band brakes today. On the motor page of that site I noticed a good deal on this brushless Kollmorgan motor with built in controller ($50). You couldn't use it on the right side of a bike, since it turns counter-clockwise, but this would be a good motor for hooking to something like a DW, if you can figure out how to get it to turn the wheels the right way. Maybe some sort of belt or chain drive that crosses over itself to form an X, or open it up and rewire it? Its only 300W, so it won't be a speedster, but I think that is all the power Brad used on the Silent Speedster?


http://www.electricscooterparts.com/motors.html

[TheKid]

I was told that those cheap motors aren't too good for bikes by a few people who bought them from that site.
I just posted that site earlier for shocks.

http://forum.atomiczombie.com/showthread.php?t=1371

They also sell left and right disc brake calipers, which are on my Streetfox, as well as disc adapters that screw onto freewheels. There are 3 adapters, two are steel, one is aluminum. I know that one of the steel ones are for discs with a different BCD than bicycles use. If the other steel one is the right BCD, they can be welded on a steel hub. I never did get to try the JB Weld for epoxying the adapters I had to the alloy hubs. It may also work.

[trikeman]

Kid did they say why? I can understand why the brushed motors (Most of what they sell on the site) would not be good for a bicycle, because they are not very efficient. Perhaps this one isn't either, but it may be a case of painting with too broad a brush (no pun intended). I think I will do some more investigation.

Follow Up Edit - Here is a blurb on someone modifying and using a Kollmorgen. 85% efficiency isn't too shabby.

http://bobmcree.com/Kollmorgen_motors.html

On the rear axle of a DW I think you could just flip the motor around to make it drive the axle the right way - no mods or complicated drive-lines required.

[trikeman]

A few more bits on the Kollmorgen. Its probably not the best motor to use on a bike (for the best you have to fork over $$$), but the price is sure right for someone that wants to try electric and doesn't mind figuring out how to make it work

http://www.endless-sphere.com/forums/viewtopic.php?f=2&p=57093

http://www.endless-sphere.com/forums/viewtopic.php?f=10&t=2771&start=0

[TheKid]

I thought the price was "Too good to be true" and posted questions on other forums quite a while ago. The only responses were a few that stated that they burned out fairly quickly. I asked around locally and found one guy who said the same thing. That one was on a scooter.
Now that you mention it, it does make sense to use it to try electric. It's a helluva lot better than forking over hundreds to find out you don't like it, or possibly wrecking an expensive motor in the process of experimentation
Also, thanks for those links. Bob McCree says he found a way to mod them so they could go forward and reverse, and sells the motors with that mod. That sure would come in handy on a quad or LWB trike. When I had my quad, I sometimes found the "Flintstone reverse" annoying.

[trikeman]

Kid. I don't think I would buy any of the other cheap motors they have, but that Kollmorgen may be worth a $50 lottery ticket. I do wonder if you would feel underpowered with only 300W. I might be tempted to buy one, if the Cabana Boy thinks its at least passable.

[AtomicZombie]

The "boy" thinks the motor would be great to mess around with, but not very good for a permanent vehicle.

Brad

[trikeman]

Thanks Brad - I couldn't resist that one.

[TheKid]

I might be tempted to buy one, if the Cabana Boy thinks its at least passable.


Cabana boy. That belongs in the Joke thread. Excellent!

For 50 bucks, it may be worth looking into for experimentation. I noticed that the recommended throttle costs 55 bucks. I don't know if that has anything to do with motors burning out, but if the people who said the motor was no good used the wrong throttle, could that be the problem? I asked about this over a year ago, so I don't know where those people are to ask them which throttle they used. I do remember one guy said he was using the cheapest method possible to add the motor to his bike, so maybe he used an inferior throttle.
At any rate, by the time you buy the motor, recommended throttle, sprockets, freewheel adapter, batteries and charger, your cost is around 200 bucks. And if it works out okay, it will probably hold up long enough to replace the motor and controller. If you set this up, even if the motor only lasts 6 months, you're not out that much. I wish I gave this more thought earlier, it would have been 15 bucks cheaper.
Would any 5k ohm pot work, or are there differences between them?

[trikeman]

Trikeman,

I tripped over this info a few minutes ago. I have no clue how valid or accurate it is:

http://visforvoltage.org/forum-topic/bicycles-and-pedelecs/478-kollmorgen-24-volt-bike-motor-needs-reversing

Thanks papa I had read that yesterday in my research. Of course if you just turn the motor the right way, the CCW is not a problem. I verified that to myself with a couple of rolled up paper tubes with arrows drawn on them.

[trikeman]

Kid - Being the garage hacker that I am, and having spilled more molten beads of solder on my leg as a kid with a soldering iron, than I care to remember, I would probably just use a $4 5k pot from Radio Shack or my parts bin. The electrical part of the throttle is just a variable resister (a potentiometer). The value of the twist grip is that you can use it like a motorcycle throttle and it has a return spring for when you let go. I would be very surprised if you could not make or find one for less than $50.

I already have a stash of 12v gel batteries from that electric lawn mower I bought, plus a few from those things you carry out to your car to start it. I suspect they are all pretty heavily sulfated, but for mad scientist work they are probably fine. I also picked up a UPS today at the thrift. I haven't put the hood up yet to see what is inside, but I know there is a battery(s) in there somewhere. Of course I also have that motor from the lawnmower, but the cost of a controller is not much different than the Kollmorgen with a built in controller.

I figure I would need a couple of sprockets and a chain to make it work. I got freewheels coming out the wazoo. If the whole thing worked and I liked it, I would buy some new batteries and maybe a better motor.

[TheKid]

That's even better. If everything was bought brand new, 200 bucks is still pretty cheap, and if the motor goes, you're only out for the cost of the motor. If you have all the parts except the motor and controller, now you're talking about 60 bucks or so with shipping, for an entire system. If the motor lasts forever, great. If not, then you could always upgrade. If I had thought about all this and asked more questions of the right people, I may have already had that system in place for a few bucks less.
So, if I understand this correctly, the Magura throttle they recommend isn't necessary, the electronics are the same as any other 5k ohm pot. So all I'd need is the motor and whatever other components I don't have. I have a lot of pots, access to tons of wire and all kinds of connectors, and several 30ah batteries that are good, as well as a few of 12ah batteries. I'd just need the sprockets and chain, or possibly a belt system to reduce noise.
Thanks for all the info and bringing this up. In the past two weeks I had 2 good deals on hub motors go south, and this may be easier and less time consuming than searching for good deals. My other alternative was to save for a few months to buy a decent hub motor. But I want to get going before the Winter sets in. Even if this motor lasts only until March, I'll be happy. By then I'll have enough for a better motor and controller. If it's still good, I'll keep it as a backup.

[trikeman]

That is my understanding on the pot, from looking at the wiring diagram here:

http://www.electricscooterparts.com/kollmorganinfo.html

Just an ordinary 5k pot hooked to a fancy handle. I doubt there is much current in the pot, since its main function is to let the controller (computer) know where you have the throttle set.

I also would not be buying any of their $10-$12 connectors, since I have a soldering gun, a set of wire clippers and a roll of electrical tape.

By the way, if you really want a heavy duty pot, you could probably adapt a throttle position sensor from a car or motorcycle if you find one with the right resistance. I just replaced one on my van but it cost $40. Here is one from a motorcycle which sounds like it is in the right range. Find a junk one and put a thumb knob on it and mount it to your handle bars.

http://www.angelfire.com/ia/z/FZ1manualTPS.htm

Or put a return spring and thumb knob on this one and go to town

http://www.radioshack.com/product/index.jsp?productId=2062356

[AtomicZombie]

The important factor is the return spring or hardware. If that fails, your brakes better be able to handle the full force of the motor.

Brad

[trikeman]

You probably also want to make sure it is a linear taper pot, not a logrithmic one.

[John Lewis]

I wonder what this motor would be like?

750W 36v geared reversible. Complete with controller etc.

http://secure.oatleyelectronics.com//product_info.php?cPath=96&products_id=737&osCsid=5a78687fe09be0a69268709d9e84ae

This is the one I used in my power trailer. Looks the same as one on one of the sites posted in this thread.

http://secure.oatleyelectronics.com//product_info.php?products_id=665&osCsid=d483b7b247ff02589fe6d8e8827c028a
John Lewis

[AtomicZombie]

If those specs are correct, it looks like a good system for the price. I must admit though, I have serious doubts about those specs.

It's like that 1000 watt stereo system you see in the department store for $39.95. Just seems too good to be true.

Brad

[SirJoey]

It's like that 1000 watt stereo system you see in the department store for $39.95. Just seems too good to be true.

Yeah, they conveniently omit the fact that the rating is bridged into 1 channel, at 1 ohm...

http://img384.imageshack.us/img384/7131/sirjoeysigmedij1.gif

[TheKid]

Another question, does anyone know about planetary gear reducers? I would rather not have such a large sprocket on the axle if possible. Are the reducers worth having?

Yeah, they conveniently omit the fact that the rating is bridged into 1 channel, at 1 ohm...



Yeah, funny how they forget to tell you that trivial bit of info.

[Penguyusa]

I just came across this thread.

It has been several months since I did the re-wiring to change rotation direction so I hope my memory serves us well.

After reading up on the Kollmorg I decided it would give good service for an e-bike. I bought 4 of them. None are yet in use but I successfully changed the direction of rotation easily. In a previous post there is a link to http://visforvoltage.org/forum-topic/bicycles-and-pedelecs/478-kollmorgen-24-volt-bike-motor-needs-reversing. The info and pic are good. It is not necessary to dig out the potting material. (I did dig out the potting material on one motor and boy what a pain that was and un-necessary too) Swap the red and black power leads and then swap the red and orange control leads. The only difficulty if you will is the builder of the motor wire wrapped the power leads prior to soldering. I was not able to easily wire wrap them during the lead change. Maybe I was having a "Monk" moment doing that.

I bought a 5K pot from Radio Shack. Mine had three leads, I only used the center and one other. Worked great especially for my test setup.

Some other folks tried the motor and controller on 36v. That cooked the controller. It is possible to take the built in controller out of the circuit and use an external controller for higher voltage. I am pretty sure some have used both 36v and 48v with an external controller. Again if my memory is correct it is possible to draw about 700 to 800 watts with these motors. This same motor build is available in a 300 w and a 400 w version. I have the 400 w version.

Hopefully I will be back to building my bikes and bike-cars before next summer. the Kollmorgs will be the power used.

[teknobike]

Hi All

I usually don't have much to contribute, but reading this thread I saw the discussion on throttles and I thought I had something to share.
My first e bike used an EV Warrior thumb control, didn't much like it, Too small and required too much effort, but it encouraged me to find something better.
Here's a link to my bike on the Austin EV page, if you click on the pictures on the right you can get a close-up of my DIY throttle
http://www.evalbum.com/2052
Its pretty simple, I used a pair of gears from a RC Car to gear up the 5k pot. The small spur gear connects to the pot and the larger gear sits on a post with the thumb control on top. It takes less than 45 degrees of thumb movement to rotate the pot 270 degrees. Under the large gear I wound a piece of spring wire to act as a return. Its works well and my total investment is less than $5 for the two gears at the local hobby shop. If anyone is interested I could take a few more photos.
Thanks for the great website!

Steve