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Discussion Starter · #1 ·
I am going to do a sport bike conversion, just doing all of my research now. I am leaning towards a Kawasaki ninja ex500.

Motor: enertrac's dual 602 hub motors at 96 volts
Controller: yet to be determined, any suggestions?
Battery pack: 96 volt 60 Ah pack with integrated bms and charger from Electric auto sports inc.

What I am looking for:
1: decent to fast acceleration
2: 45 mile range

However, I am a little confused about how the dual motor aspect will affect the bikes performance. I assume they are wired in parallel but I don't know. If so, how does this affect acceleration and power consumption?
Any and all comments, suggestions and constructive criticisms are welcome and wanted. Please post what you think about the project!
 

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How do you mean dual motor? Two motors in one hub on the rear wheel? or one motor on front, one on back? I'm not famiiliar, so forgive me.

I think Mark uses Kelly. I'd ask him what he recommends first.

What brand batteries? Just wondering, I sell batteries as well... GBS cells/bms/charger.
 

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http://www.ev-propulsion.com/motorcycle-hub-motors.html

They sell a dual motor setup now for sport bikes....peaks at 60kw...



Off Topic:
It would be awesome to see a lightweight car like a miata with all the wheels driven by these motors. 8 motors, 10ke nom. & 30kw peak each = 240kw peak, 80kw nominal total, each motor supports 400 pounds, so 8 support 3200lbs, lightweight lithium pack would work.
 

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Discussion Starter · #5 ·
I emailed a few companies for quotes, but i think i am going to go with a 2nd generation GBS Lithium battery pack. I am looking at the 40AH 96 volt pack (https://www.electricautosports.com/node/451) and the 60AH 96 volt pack (https://www.electricautosports.com/node/445). Trying to figure out with pack i should get. The 60AH pack at $4000.00 is almost too much money for me... but from my calculations, to travel 40 miles at 70mph I need ~53AH 96 volt pack.
 

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you'd be really pushing a 40 ah pack hard, well beyond it's specifications for peak power, with those motors and a controller to support it. Heck you'd even be pushing 60ah cells, not beyond their rating, but certainly enough to cut their lifespan a bit to lower than the advertised 2000 cycles.......
 

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Discussion Starter · #9 ·
Is anyone keen on how exactly these nub motors work? For the dual MHM602, is a 144volt pack ideal, so that each motor gets 72 volts? I am not entirely sure how this works. Does each motor getting 72 volts mean each pull half of the amperage provided by the controller at any given moment, and if so, does this increase overall power or overall efficiency?
 

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Doesn't work like that. These are brushless motors. They're essentially position matched and then fixed in place so that the coils are in series or parallel. The controller still gets 144V, but it depends on how Mark has them hooked up. I wouldn't wander far from what he's done.

I think most times I see dual brushless motors, they're put in parallel, so each motor would be getting a modulated 144V signal, each motor at half the amps.
 

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Pretty much, but it's 3 phase, so it's a little more complicated.

but assume that the whole thing is really 1 motor, and there's just 2 sets of coils where there'd normally be 1. Each get half the power.
 

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so what exactly are the advantages then?
Assuming that they're in parallel, each motor would get the full voltage for maximum rpm; and assuming you have a controller that's rated for twice the peak and constant current of each motor, you would have twice the torque you would have with one motor.

That means you can move a heavier load easier, or you can accelerate a lighter load faster. An EX500 is a light bike, so you have to figure out whether the additional weight you're adding with another motor and more batteries is worth more than what you'd be losing over the single motor/smaller pack, lighter version.

That comes down to how you will be using the bike (city, highway, combined, etc), how much you weigh, and will you be carrying passengers or "cargo"... If you're in a lot of stop and go traffic, climbing hills, stoplight "racing" and/or tugging a lot of weight, the additional torque will help. If you're going putt-putt to work, with very light traffic, on flat roads, you may not use it enough to justify it. You have to figure out your needs. It's hard for us to provide much valuable input without data.
 

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Discussion Starter · #16 ·
I have actually decided to go with a heavier bike, in the 750cc-1300cc range depending on what i can get. As far as what i am looking for in this bike (if this helps at all with giving me advise as to whether or not dual motors is better than one):
1. a top speed of about 80mph
2. a range of 40 miles (I wont be driving this range everyday, but i need it to commute from my apartment to my work a couple of days a week)
3. I would like some sexy acceleration, say around 5-6 seconds 0-60 or maybe a little faster.
4. I weigh 160 pounds and should not be carrying any cargo, maybe a light backpack.

Right now i am keeping my eye on salvage auctions for a bigger sport bike but they keep moving out of my price range. Do you think that a 600cc bike would have enough room for either dual motors or an ac20 with the amount of batteries i need to go 40 miles at 70mph? Sorry about not having any official data, it is because i still dont have a bike and am not sure which one i am going with simply because the price and size are the biggest factors.
Also do you have a motor and control combo that would work well as a dual motor setup and is compatible with my expectations? Btw I am expecting my dry weight to be about 425-500 pounds
 

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Discussion Starter · #17 ·
Also, I was told that in order to achieve those goals for my bike, I would need a bigger bike, do you guys think a 600cc bike is too small for what I am trying to do? To be honest, I dont care which brand/model bike I get, as long as it looks sexy and holds what i need to put in there.
 

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AC20 would work well. There's plenty of power (~45HP peak). I know quite a few that have used it. The performance of the AC20 will get you at least 80mph and the range you need should fit inside of a 600-800CC bike. I like the AC15 and AC20 systems because the motor is built well, and the controllers are pretty bulletproof. That's why I chose to start selling them (www.emf-power.com). I'm partial though, because I own one.

I can fit 5kwh in my VFR (V-four). Inline engines are a bit better because once removed, the frame is wider, which is great for batteries. My frame is thinner than most.

You'll likely have enough room 5-6kwh in there, an AC20 and a decent charger.

Are you thinking crotch rocket? or more of a cruiser?
 

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What year?

Get new as you can. You'll spend less on immediate maintenance like head bearings, wheel bearings, brake lines, brake pads, rotors, tires (maybe), brake fluid, fork seals/fluid, etc.

The YZF-R6 looks like a nice bike. I almost bought one!
 
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