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And my very efficient device (except for the aerodynamics) with an 11 inch motor would still only do 59 mph with 130v

I am willing to believe that kelly controllers no longer deserve their old reputation as boat anchors but you are still wrong about the voltage that the OP will need for his 13 inch motor

I suspect that the OP and I expect something just a tiny bit different from our vehicles than you seem to want

My device is used on the track as well as on the road
 

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Hey Dunc,

Find it strange that ekthor is bragging about his newfound "quality" Kellies being able to operate up to 60 or 70% of their rating, or having to return it only twice? Looks to me like he is using this thread to sell stuff. And his insistence that larger motors suck more amps (meaning less efficient therefore less range), to me, indicates misunderstanding and misapplication, not a reasonable characterization of electrical machinery.

So readers beware. Mr. ekthor offers some valuable experience but loads it with ulterior motives (sales) and opinions, some of which I find questionable.

Regards,

major
 

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So you have HUGE torque but SLOW RPMs with that 13" motor beast, you need a gear AMPLIFIER, as opposed to a gear reductor like the built-in gear reductor every VW Acapulco or "Safari" has, (as we know it here in Mexico), I haven't seen your EV specs but certainly if there is a transmission, you have to skip 1st and 2nd gear from 0 RPM all the time, you need to start in 3rd gear.
The motor in Duncan's Device drives the input of the final drive (differential) without additional gearing; it runs as if it had a traditional transmission and was always in the direct (1:1) gear.

I find it strange, at the very least, to declare another builder's design to be faulty without even knowing what the design is.

Also, overdrive or step-up gearing is not an "amplifier", any more than reduction gearing is an attenuator.

Why AMD stopped their DC Series Motor production remains a mystery to me, I assume they followed the absurd argument of the Automotive Industry "DC Series Wound motors are obsolete because they are less than 90% efficient, they do not offer regen and they need maintenance" so everyone is moving to AC or PM rare earth reluctant motors for twice or trice the cost... to get 8% more efficiency? Absurd!
If you don't understand that doubling the cost of one component is well worth the expense for substantially greater efficiency and avoiding maintenance (and failures), then you don't understand the automotive industry at all.

So far, in EvAlbum AMD/Advanced DC Motor is "the most popular motor used for conversions." It's Not the HPEVS AC50, not the Warp 9, it is the AMD/Advanced DC 9" motor.
It shouldn't be surprising that a historical collection of do-it-yourself projects by people who can't afford current technology is dominated by old forklift truck motors, many with a new label on them :rolleyes:, or that people assembling vehicles with extremely limited development resources have most often chosen the simplest design. :eek:

And THE most popular controller (because I believe it was the first is the OLD and OBSOLETE CURTIS), Curtis is using the same old technology since the 90's (perhaps the 80s, not sure)...
Now that's bizarre: dismissing modern motor technology as absurd (in favour of motor design from over a century ago), but attacking a newer controller technology as old and obsolete. :confused:
 

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Hi ekthor,

No need to go thin skin. I'm OK with the mention of product offering provided Duncan (admin) is also and you don't get carried away. And opinions are welcome AFAIK. Just don't get upset when you see differing opinions.

Regards,

major
 

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Discussion Starter · #28 ·
Lots of good useful info here and I do appreciate the ranges of both opinions and methodology in which you guys have gone about putting your projects together. The more information I have before putting things together and buying things the better.

I will be using this motor, I do understand there are many more options that would be better suited for both performance and range but it’s what I have and I want it to work for the fun of doing it.

I’m glad to hear there is a more budget friendly motor controller available and I’ll be sure to check out the Kelly products for sure.

I’m searching for reasonably priced battery’s and a motor controller at this point so if anybody has a good deal to be had let me know.

Thanks
 

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Hi Blake,

Nice find on the 13" GE!

I'm running an 11" GE forklift motor in a light car for both street and drag strip. My motor has been modified to handle more power than nameplate specs, and is working very well at 200 motor volts and 2000A.

The 13" can certainly make more power than the 11", and could power that Nova very nicely. Look at the Rocket Bike which also used a 13" GE motor, but, it was heavily modified and driven to high voltage and current using a Zilla 4k controller.

Your *stock* 13" GE can probably take up to 170V and maybe 2000A for a few seconds, but that may be pushing it.

The Z1k with a 144V pack would be max of 192 battery hp, and with voltage sag under full load, that would likely drop to 155 hp or so. You might not be satisfied with the drag strip performance.

If you are looking for much better performance at the track, you will want more voltage and amps. Get as much as you can afford. i.e. if you double pack voltage to say 288 and go to a Z2k, it would make 500+ battery hp and your Nova will be very quick.

Looking at the pictures of your motor, the brushes may be worn down enough to consider replacement. A proper brush and comm break-in would then be needed as well as blowing out all of the old (and break-in!) dust in the motor. As you suggest, increasing motor timing will help with higher RPMs.

Regarding highway speeds and motor rpm, it largely depends on gear ratio you choose for the rear end. My car is direct drive with a 2.73 rear end, at 55 mph it's running below 2000 rpm. The 11" GE has enough torque so even at this "overdrive" ratio, the car has traction problems below about 25 mph.

Your 13" can produce considerably more torque.


Wayne
 

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Discussion Starter · #30 ·
Thanks for the input Wayne. It looks like you have the setup and performance characteristics that I’m looking for.
To get your 288 volts and decent range how many battery’s are you running? I’m looking at getting the LiFePo4 battery’s and before I calculate out everything for my battery pack I just wanted to hear some real world experience as far as range and performance that you are getting.

Also which car are you running your setup in? And are you direct drive? I’m considering that but am concerned that setting up reverse on the DC motor is more trouble than it’s worth. Seriously considering fabricating an adapter plate for my trans and going that route.
Thanks!
 

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My battery pack is a 4P84S pack of A123 pouch cells and is 21kWh in size. The Zilla log data says it's making 542 battery hp, the BMS says its more. The car is a replica of a '65 Cobra and weighs about 2140 lbs without driver.

If driven gently, it can go more than 60 miles on a charge, although I don't push it that far, usually limiting drives to 40-50 miles.

It's set up as direct drive currently, but I'm planning to add a Lenco 2 speed to improve bottom end punch. It previously had a modified Powerglide, but I couldn't keep low gear in it, due to the inability to create enough transmission fluid pressure and flow volume with an external pump. It takes at least 200 psi to lock up the clutches sufficiently, otherwise they fry after 50-75 hard launches. The Lenco won't (shouldn't ?!) have that problem.

If you are going to use a transmission, make sure you have a good plan to provide fluid pressure. The transmission's internal pump doesn't make any pressure when the motor isn't spinning. You can get away with lower pressure (maybe 140psi) if you don't plan to nail it hard from a stop.

Your 13" GE is a torque monster, plan accordingly. My 11" GE was able to twist the OEM input shaft on the Powerglide.

Regarding performance, with direct drive it's doing 0-60 mph in 3.0 seconds. With the low gear from the Powerglide, or Lenco, it is definitely quicker.


For reversing the motor, it's easy to do with 4 contactors. I can provide a diagram for this if you are interested.

Wayne
 

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Discussion Starter · #32 ·
Hi Wayne and everybody else on this thread. Would you be able to send me a diagram of the reverse contactor setup. Also what contactors are you using and where did you get them from? I’m getting moving on the project and that would be a big help!
 

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Here is a diagram and a picture showing my reversing contactor setup.

I'm using Gigavac contactors for the reversing contactors, Kilovac EV200 is another good choice. For the main contactor, a Kilovac Bubba is used as it's better suited to break high current in an emergency.

The top of the Bubba is seen in the picture between the Zilla and the Hairball. The forward/reverse DPDT relay is attached to the side of the Hairball enclosure, and controlled by a switch on the dashboard.


Hi Wayne and everybody else on this thread. Would you be able to send me a diagram of the reverse contactor setup. Also what contactors are you using and where did you get them from? I’m getting moving on the project and that would be a big help!
 

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If torque is a concern, why not current limit it to avoid the extra stress on batteries and driveline?
 

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Discussion Starter · #35 ·
Does anybody know where to find a drive coupler for this motor? I’m also in the process of trying to figure out what trans is the easiest to use. Also a direct driveshaft yoke would work but where an I buy one? The th350 thats In it might be more trouble to connect to than its worth. I know EV west uses the power glide setup which works well. Thanks
 

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Hi....The bobber as a concept is cool, and well suited for electrification. But recreating the cylinders/cylinder tops cooling fins? Ok, I guess if you are going to run a liquid cooled motor or controller that could work as a radiator replacement, not as efficient as a radiator but it could still work. As long as you don't run liquid cooling, I think you are sinking countless hours on recreating something that might not be that cool after all when bike is all done and ready. All that time and machining into something that does nothing, has no function,adds nothing to performance, or in any way really. I would frankly just drop the idea of replicating the engine fins, after all you do an electric bobber. Don't be shamed by that.
 
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