# Budget friendly/Easiest to tune 70ish kw motor?



## storx (Nov 24, 2013)

Since the original engine used in the platform im going off of for my build is 75kw-ish, what 70ish kw motor would you use if this was your build?

The bike i am designing my EV build off of has listed dimensions of 24.5" from bolted points of the front edge of the engine cowl to the rear edge, basically giving the rough dimensions of the engine compartment length being utilized to mount the bike engine, most of the 50kw motors i have seen are 12-14inchs wide.. i would be able to greatly shorten the bike by as much as maybe 12-18 inches...


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## dcb (Dec 5, 2009)

if you are feeling brave, running an ac24ls in delta at 312vdc and 268adc amps should hit 70kw at 6000 rpm. You find them here and on ebay in the sub <$300 range. easy to tune will be a function of the controller, would you find an open source controller easy to tune? You WILL need a much larger sprocket and/or jackshaft looking at that picture. Limit the high end of the gearing torque to about the traction limit of the tire (you could weigh it down the right amount in the right places, lock the rear wheel, and see how much force it takes to drag it backwards to get in the ballpark, then fudge in some torque for accelerating the mass of the driveline/wheels) torque it till it smokes if you like burnouts, back it off a 1/4 turn for painless launches.


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## storx (Nov 24, 2013)

has there any any success on that motor being tuned? i have actually looked into that one, i see it on a lot of boards for builds.. but out of the 30+ builds i seen it used in.. no end result was finalized with the motor... 

Most seem to have a gearbox already..


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## dcb (Dec 5, 2009)

I saw a ninja with one hanging off the side a while ago, but it mysteriously disappeared.

if you get a matched dmoc controller with it, there are some tuning hints in the controller manual
http://media3.ev-tv.me/DMOC645_User_Manual.pdf

if you go with an open source controller, it stops being easy, but you won't be dealing with proprietary hardware/software/secrets, which might not even be available, and will probably learn an awful lot in the process. It has the potential to be budget friendly, but not at all time friendly at this stage. I prefer the keyed C-face versions, never thought about using the gearbox on a bike/trike.


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## dcb (Dec 5, 2009)

fyi, you should probably consider DC motors as well, they don't "tune" the same way, with fixed timing and etc, but can be fairly budget friendly and make lots of power. Especially if this is a "toy" that you don't put tons of miles on. The big expense is batteries in either case, usually.


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## storx (Nov 24, 2013)

I thought about going DC, because that would greatly simplify this all, but i dont really see any DC motors above 28kw, i plan on building my own battery pack out of 18650 cells, i bought laptop batteries on ebay and overstock.com when i built my electric recumbent bicycle 2 years ago, but i didnt have to go into details on motors and such because i just bought a hub motor kit off ebay to simplify it all and i have over 4,000 miles on that hub motor now with my occasional rides during the week.


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## dcb (Dec 5, 2009)

I think, basically they use a lot of volts to force more amps into a dc motor, being mindful of saturation (or not), and make adjustments to the brush timing, or even adding brushes. Possibly even rewinding for higher insulation or other characteristic. Then they just keep an eye on the temperature and don't flog the motor all the way to failure. AFIK the top dragsters at NEDRA use DC motors and hundreds of volts. They are a far shot from 28kw, which is a far shot from a 250W hub motor 

Your trike is going to be traction limited though, one rear drive wheel without much weight over it. And a low and forward cg, so the wheel will have a hard time getting under the mass of the trike on launch. You might want to think about how much torque you can actually utilize on the rear, and what sort of top speed makes sense for your environment.

The original was probably way overpowered, couldn't really make use of all of it anyway, at least in the lower gears.

confirmed, at sub ~80mph, overpowered reverse trikes role in life is a 1 man burnout machine  (hard for me to get too excited about...)
https://www.youtube.com/watch?v=nMlWlkCnf3Q


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## dcb (Dec 5, 2009)

if you want to accelerate fast, the high cg of a motorcycle will help a lot with traction (and weight). Smoking a tire gets old.

Suzuki GSX-R1000 2005 0-60: 2.35


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## Tomdb (Jan 28, 2013)

What kind of budget are we talking?

Final vehicle weight, or rolling chassis weight? (So i can crunch some numbers)

Easiest setups would be matched HPEVS motors and controllers.
An ac34 or 35 might be a good match.


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## storx (Nov 24, 2013)

dcb said:


> I think, basically they use a lot of volts to force more amps into a dc motor, being mindful of saturation (or not), and make adjustments to the brush timing, or even adding brushes. Possibly even rewinding for higher insulation or other characteristic. Then they just keep an eye on the temperature and don't flog the motor all the way to failure. AFIK the top dragsters at NEDRA use DC motors and hundreds of volts. They are a far shot from 28kw, which is a far shot from a 250W hub motor
> 
> Your trike is going to be traction limited though, one rear drive wheel without much weight over it. And a low and forward cg, so the wheel will have a hard time getting under the mass of the trike on launch. You might want to think about how much torque you can actually utilize on the rear, and what sort of top speed makes sense for your environment.
> 
> ...


Ya, i never understood why they only use an 7.0 inch wide rear tire on the bike, there was a guy in North Carolina i helped out on his reverse trike build using a Toyota car engine for powerplant and we had to upgrade all the way up to an 12 inch wide rear tire to prevent burn outs on full acceleration, but that was an 240hp engine in that build..i was thinking of shooting straight to a 10inch rear wheel for traction, with the use of an electric motor i think i could shorten the bike a significant amount to reduce the fish-tailing effect the longer trikes suffer from


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## storx (Nov 24, 2013)

Tomdb said:


> What kind of budget are we talking?
> 
> Final vehicle weight, or rolling chassis weight? (So i can crunch some numbers)
> 
> ...


I am not sure on the budget as of yet, i am planning on doing this as i go.. i do know i dont want the bike to be a slow slow turd, not fun to ride if want to push the pedal to the floor...

The Scorpion P6 with petrol engine is about 700lbs, the R6 engine and assembly from searching around is around 230-240lbs when you include all of the hoses, wiring and such.. so an electric motor under 200lbs should place me around similar weight i would imagine in total since i plan to use 18650 cells and they are very light....


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## storx (Nov 24, 2013)

I also plan to only extend the battery capacity to maybe 60-70miles at most, atleast 50 miles range.. i plan to reduce the cost on batteries on the bike and build a small towable trailer that i can mount an off the shelf gas generator to as well mount maybe an additional amount of battery capacity low on the towable trailer for longer rides.. i want this to be just something i can enjoy to work and back and around town with friends mostly, my current motorcycle i barely go over 50 miles in a night just riding to somewhere to hang out and riding back.. occasionally there are longer rides that the trailer setup would benefit me, since you can easily find an gas generator off the shelf with 240v 30amp output, seen one at homedepot before..


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## dcb (Dec 5, 2009)

Ah, the innocence of newbiness 

you would need roughly 2800 18650 cells, pushed pretty hard, to make 70kw. it would be about 300lbs just for the battery, but it would have about 23kwh so the range should be fine (if you don't run at a constant 70kw). It will be at least $10 grand in cost.

A generator will probably get worse mpg than the original.

Typically, by the time you are considering a trailer/hybrid, it makes more budget friendly sense to keep a 5 speed econobox in the barn for longer trips.


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## Tomdb (Jan 28, 2013)

Sorry dcb, this is nonsense. You just have to pick the cell that has the correct balance between max output and energy density (Wh/kg)

You can build a pack with less cells, all comes down to how hard you are willing to push your pack. 

200kg for the roller, lets say roughly, scorpion p6 is about 330kg minus engine that gets roughly that weight.

Now because the roller is so light, personally i would go with an Emrax motor and Bramocar controller weighing in at around 35kg total. However an Hpevs ac34 plus Curtis 1238 wieghs total of 50 kg so not that bad.

Then an pack based on a 18650 cell, lets say the Panasonic ncr-18650B of the size of 15kwh comes in roughly at 75KG. Still costing roughly 6000-7000$ for cells alone.

Total weight of the trike would be around 350kg when all the mods are done, taking some extra weight for charger and dc/dc into account. This would be a very fun package.


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## dcb (Dec 5, 2009)

It is the right order of magnitude, hardly nonsense, but good to know about the ncr-18650Bs, do you know a good source (link?)

still it sounds like ~1200 batteries to assemble to get to 15kwh, not trivial. But 15kwh should give decent range on a trike. To feed the ac-34 @ 48v&650A each cell would need to make 26 watts, which puts each cell at an average voltage of about 3v @ 8.7 amps after internal losses, so roughly 2.6C, not horrible, but out of manufacturers recommendations (assuming I have the right datasheet)


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## storx (Nov 24, 2013)

what about something like this? from the forum i found the link to them, if you order 4 of them, they are letting them go for 4 @ $3500
http://www.evwest.com/catalog/produ...ucts_id=329&osCsid=6lu2ggeujb93b7mub8jf7umjk5


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## Tomdb (Jan 28, 2013)

Read the specs.
150Amps peak and 57 volts so no where near what you want.

You would need two series to get the max voltage for the controller and then as many parallel as you can fit. If you can even fit them. Two parallel is not going to cut it for the amperage.

Building 18650 packs is not trivial but with a decent spotwelder and module plan its not "that hard".


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## dcb (Dec 5, 2009)

assuming [email protected] peak, and a budget, and a penchant for easy to use, you might consider something besides the 18650 format.

i.e. bolting 18 ca180FI in series:
http://en.calb.cn/product/show/?id-629

continuous current rated at 350a. roughly $230 apiece, Should be about 0.5v drop/cell at 650A. (claimed 10C/1800A for 10 seconds, though you would need 28 cells to hold 48v).

so a 223lb 10kwh pack, for about $4000, and bolting 18 cells together is infinitely easier than spot-welding 1200 cells together.

though I'm not familiar with ~48v systems, the trend seems to be going towards hundreds of volts, to reduce the current for a given power level, and the losses in switches/diodes. 

But ~48v is definitely on the "easy" side of DIY, esp in terms of hazards, esp for a newbie. 650adc is a fairly large inverter though, the peak motor currents will be about 1000 amps, that is some hefty switches and heat.

Just saw this...


storx said:


> ...and we had to upgrade all the way up to an 12 inch wide rear tire to prevent burn outs on full acceleration,


FWIW, my understanding is that the width of the tire doesn't make a huge difference in traction, I suspect the weight of the bigger tire had more to do with it, preventing it from spooling up faster (and slowing vehicle acceleration), but I've been wrong before, maybe it was a better compound. But the gsxr example has a fairly narrow (and rounded) tire and low 2 second 0-60, case and point. the trick is putting all the weight on the drive wheels (while minimizing weight overall for good acceleration), and since the gsxr CG is high (esp with a rider), and not very far in front of the axle, it isn't hard to do on launch.

I should probably disclose I've never been a fan of trikes, not when a bike can do so much more. There are plenty of comfortable ones for long trips, even some recumbent ones with streamlining for great efficiency/range. A trike always seemed like the worst of both worlds to me (with rare exception)


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## storx (Nov 24, 2013)

Ok, i have been doing more research on the AC24LS motor and controller, it seems like they are hard to find, maybe they are a discontinued model? most of the sites i found selling them displayed them as out of stock.. i will keep my eyes open for one as they seem together go for around 1000-1500 motor and controller, which is a reasonable price for that size motor...

Other option is what are the disadvantages of going dual motor? like dual ME0913's or ME1003's?

Another option i came across was yesterday i went up to local salvage yard that listed an 2011 Chevy Volt w/53k in stock, talked to them for a bit and they would be willing to part the ENTIRE battery assembly for $900, the motor may not be salvageable, as the drivers corner is what took the brunt of the damage, but i am going to go back later this week to look at the car more to see if i can see any damage to the electric motor, because if i bought the battery and motor assembly, he do it for $1500, which would include both motors, controller and charger... the top one looks to be damaged, which i think is the charge controller from what i could see


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## Tomdb (Jan 28, 2013)

the batteries at that price are a steal. 

Motor controller is too much work. Dual brushless motors are okay, but require two hefty controllers to get 70kwh.

If you want a good deal look at the emrax and the bramocar controller in the classified, however it might be a bit pricey for what you want.

What is your location by the way, america?


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## storx (Nov 24, 2013)

Tomdb said:


> Read the specs.
> 150Amps peak and 57 volts so no where near what you want.
> 
> You would need two series to get the max voltage for the controller and then as many parallel as you can fit. If you can even fit them. Two parallel is not going to cut it for the amperage.
> ...


Ah, now i am starting to understand what you guys are talking about more so.. atleast i think i am...

When i built my ebike battery pack using laptop 18650 cells it was honestly not a hard task, i bought one of those grids off ebay that you snap the cells into and just soldered all the connections by hand.. no spot welding.. ya it was time consuming, but it worked perfectly and has been reliable ever since... i run that pack all the time on the bike, i even tow my canoe with the ebike drivetrain down to the local park to go out on the water using the bike paths from my area... 

The 18650 cells i got out of the laptop batteries were a mix of name brand and chinese clones, nearly 50/50 ... granted the chinese batteries had slightly less capacity when i tested them on the iMax i bought, are they not worth using? i found that a lot of the HP laptop batteries i bought had chinese cells in them while laptops like samsung or lanova had real batteries..


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## Tomdb (Jan 28, 2013)

You need real brand name cells when constructing large packs. Otherwise you can have a large variance of current sharing and total energy per parallel set. This will give you an unreliable pack which will fail prematurely and never give you the performance you calculate.


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## storx (Nov 24, 2013)

Tomdb said:


> the batteries at that price are a steal.
> 
> Motor controller is too much work. Dual brushless motors are okay, but require two hefty controllers to get 70kwh.
> 
> ...


I am in Florida, USA
The battery assembly for the Volt now that the Gen 2 is out and no real amount of failures have occurred has seemed to drop the value of the gen 1 batteries now.. plus with the release of the Tesla home battery on the market, someone already took one apart when i was googling and found it to have the same 330cell 18650 containers that are found in the Tesla model s apparently, so its becoming a new source of batteries


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## dcb (Dec 5, 2009)

dunno about all that, a link would be helpful (and a link from tom for a good source of cells).

if range is important, then you might think about regen, and if you are thinking about regen, you might think about front wheel drive (or 3 wheel drive).

In any event, your battery pack has to support the power demands and the range demands. power (expressed as watts or kw) is volts * amps. energy is watts * time (i.e. kwh). how many kw will your trike need to go a mile at a certain speed? How long do you maintain that kw consumption to get where you are going? How many kw do you need for full throttle acceleration?

chances are you can get away with a lot less than 70kw for commuting purposes. But if you want more power it will cost you. rough guess is my bike could cruise on the flats with no wind at 60mph using 11kw. But I need to fudge some in there to account for wind and hills (and/or fun)


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## storx (Nov 24, 2013)

dcb said:


> dunno about all that, a link would be helpful (and a link from tom for a good source of cells).
> 
> if range is important, then you might think about regen, and if you are thinking about regen, you might think about front wheel drive (or 3 wheel drive).
> 
> ...


Honestly, i am not looking for a LONG range on the batteries, goal is around 50miles to do what i want out of it.. I want to extend the range out of using a attachable generator to supply power high enough to allow highway driving at minimal up to 75-80mph....

I am still learning about generators and supplying power so that is another topic, i am thinking along the lines of how the chevy volt works, how the gas engine rotates the electric motor half the size of the drive motor to generate enough power to maintain highway speeds up to 100mph, at 75mph the volt is only using 38% of its charge motor's potential to maintain speed...i am wanting to learn if a off the shelf generator is capable of supplying this, or i may need another off the shelf motor driven by a petrol engine in a custom setup to provide this step...

DCB, what is your ideas on dual or 3 motors?? see that you can get ME1003 kits with controller for $1450 or 2 motors and 2 controllers for $2200 or 3 motors and 3 controllers for $3000..
Why does each motor have to have a separate controller?? why not just one larger capacity one powering 2 motors? sorry if these sound like dump questions, i just have very little understandings of the engineering of the can and cant things to do with electric motors..


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## Tomdb (Jan 28, 2013)

each motor has its own timing, and matching the timing is too big a fuss. Needs to be too accurate.

The more powerful your controller gets, usually goes with a more expensive controller.

This means more bang for the buck when you get a matched motor and controller. An motengery and matched sevcon, preferably highest voltage you can get are some of the best value for money.

I would not worry about the going long distances with the trike, I would first ride it before thinking about increasing range.

ME1003 is a brushed dc. So requires maintenance also are quite prone to overheating with heavier loads.


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## dcb (Dec 5, 2009)

I think front wheel drive is worth at least thinking about, esp on a tadpole. I lean towards inboard motors (not hubs) because hubs are unsprung weight (affects handling) and more weight at the extremities(harder to start turning, harder to stop turning). Plus with inboard sprockets you will have an easier time experimenting with different gear ratios. 

Making it 3wd would be fairly trivial after that. But it solves most of the issues, all the weight is available for drive traction regardless of configuration, and is more optimal for regeneration as well.

So you want a continuous 80mph it sounds like... There is a way to narrow down the power required if you have a working trike, and that is to perform coast-down testing (perhaps with a few different weights). you weigh the trike (can be done one wheel at a time) and yourself, get it up to speed and put it in neutral on a flat with no wind, then note how long it takes to slow down to various speeds and coast to a stop. The distance to stop/slow is a function of the weight and the resistance. There is more to it, just putting the idea in your head.

Edit, also always buy the batteries last. Have an idea what you want so you can design a space for them, maybe some cardboard mockups, but don't buy them and leave them sitting around and aging, no telling how long till the project is complete. And chances are they will be cheaper in the future.


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## dcb (Dec 5, 2009)

fyi, making a real rough guess using the figures here:
https://www.slingmods.com/blog/pola...pagna-t-rex-campagna-v13r-morgan-3-wheeler-2/

150mph top speed
730lbs (call it 1000 with rider and etc)
126bhp

futzing with the calculator here:
https://www.rbracing-rsr.com/aerohpcalc.html

randomly putting in .4 for cda, 150 for speed, 1000 for weight
I play with frontal area and recalculate till I get ~126hp

so a value of 12.5 for frontal area seems to work well enough.

cd and a (frontal area) aren't critical here, just their product, .4 *12.5 = which gives us a cda at 150mph of 5.

so I will leave those values alone and change speed to 80mph
on recalculate it says you will need 21hp (not including electrical losses/etc) to maintain 80mph. 

there are 746 watts in an hp, so you need ~16kw continuous, call it 20kw after all the losses for a wide margin of safety.

watts are volts*amps, so a 72 volt system would need to be able to sustain 278 amps.

a 144 volt system would need to sustain ~139 amps.

a 288 volt system would need to sustain ~69 amps, all the same wattage.

etc. etc. but you can then use the estimated amp draw at different speeds to figure out the range. i.e. if you went a constant 80mph on a 72 volt system, and had a pack that was 100ah, it would run out in 100/278 hours or about 21 minutes (if you are flogging the pack at 100%) and of course 21 minutes at 80mph is 28 miles.

Most people don't expect a lot of range at high speed. The losses with higher speed are exponential, if you go back to the calculator and put in 40mph, you get a required hp of 3.52! lets call it 4hp for 40mph or about 3kw. your 72v 100ah pack would deliver 3000/72 or 42 amps. it would run for 100/42 hours or 143 minutes, and travel abut 96 miles...

a 72 volt 100ah pack is 72*100 wh or a 7.2kwh pack. you won't be able to goof off if you need full range that trip. 

so a 14.4 kwh pack should be able to get you 56 miles @ 80mph, if you push it. But that is 2x the number of batteries and cost for 1/2 the range of 40mph.

The calc says 15.6 hp needed for 70mph, so at that speed a 12% reduction from 80mph gives you a 35% increase in range.


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## storx (Nov 24, 2013)

dcb said:


> fyi, making a real rough guess using the figures here:
> https://www.slingmods.com/blog/pola...pagna-t-rex-campagna-v13r-morgan-3-wheeler-2/
> 
> 150mph top speed
> ...


I really really enjoyed this post man, this brings a lot of answers to questions i have together. My only question is why is watt usage so high on motorcycles? like my 2013 chevy volt i get on average 50-53miles on 10kw, so right around 500watts per mile...

Have any thoughts on using a trailored small generator for long distance power?


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## dcb (Dec 5, 2009)

storx said:


> I really really enjoyed this post man, this brings a lot of answers to questions i have together. My only question is why is watt usage so high on motorcycles? like my 2013 chevy volt i get on average 50-53miles on 10kw, so right around 500watts per mile...


fwiw, a trike is typically a bit draggier and has more rolling resistance than a motorcycle, ie. my gs750 comes in at a cda of 4.5.

also, I've included rolling resistance in the cda figure, so that error will be greater at lower speeds.

but I'm not sure where you got that idea from, and you did not indicate the speed of travel (which is a big factor) in your figuring. plus you probably mean 10kwH and 500wH.

from:http://electricmotorcycleforum.com/boards/index.php?topic=2828.20;wap2
"And the kWh/mi for the Zero S ZF11.4 is:
10kWh/137mi = 73Wh/mi city
10kWh/93mi = 107.5Wh/mi combined
10kWh/70mi = 142.9Wh/mi combined

And we have the Brammo Empulse R/E1:
9.3kWh/121mi = 77Wh/mi city
9.3kWh/77mi = 120.8Wh/mi combined
9.3kWh/56mi = 166Wh/mi combined"

and from our own figures:
20kw/80mph=250wh/mi
3kw/40mph= 75wh/mi (probably low because rr (rolling resistance) isn't calculated separately)

Also 500wh/mi is on the high side for a volt, you might want to adjust the nut behind the wheel  (look up hypermiling to get a basic education on where you are wasting the most energy)




storx said:


> Have any thoughts on using a trailored small generator for long distance power?


re: generator, don't like 'em, inefficient, drive the volt for longer trips, or have the engine drive a tire directly (i.e. electric motors driving the front wheels and a small/ range optimized ICE pushing the rear), aka parallel through the road. the electrical path will have several losses along the way, and improving that is way beyond most folks. I could see a real small generator for some sort of emergency, but not on a daily driver.


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## storx (Nov 24, 2013)

dcb said:


> fwiw, a trike is typically a bit draggier and has more rolling resistance than a motorcycle, ie. my gs750 comes in at a cda of 4.5.
> 
> also, I've included rolling resistance in the cda figure, so that error will be greater at lower speeds.
> 
> ...


Firstly, the 500 watts quote was a type-o, sorry i was meaning to say around 200 watts, fat fingered it on the phone

When i unplug my car from the charger it says it charged 10.0 or 9.9kw from dead empty on the screen, so those 50-53miles im talking about is over that 10kw charge.... The actual car was advertised at 35miles over that 10kw charge.. but i am netting far better

Comparing it to a Tesla it looks like crap, but something like a BMW i3 it does way better.. I had an i3 for 3 days when i was thinking of trading in the Volt up to the BMW i3 and driving the same route i take the volt, i was getting only 78 miles on 2 of those 3 days and on the 3rd day i only got 75 miles on an 18.8kw charge from my charger. 

So...
Volt averages 189 watts/mile
BMW i3 averaged 241 watts/mile


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## dcb (Dec 5, 2009)

still to many variables/unknown for the casual reader to say, i.e.

are you measuring from the wall? same charger?

weather conditions for each drive (temperature especially)?

peak and average speeds

terrain

traffic

tire inflation

cargo

did either one use the engine at any time

generally though the i3 does seem less efficient just at the cda level, which is ~5% worse than the volt. 
http://insideevs.com/car-driver-aero-comparo-tesla-model-s-versus-volt-leaf-prius-video/
Toyota Prius – .26 Cd, 6.2 feet CdA
Tesla Model S – .24 Cd, 6.2 feet CdA
Chevrolet Volt – .28 Cd, 6.7 feet CdA
Mercedes Benz CLA 250 – .30 Cd, 7.0 feet CdA
Nissan LEAF – .32 Cd, 7.8 feet CdA


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## storx (Nov 24, 2013)

Hello guys, well i went ahead and purchased the dual ME0913 kelly controller kit, i talked to them about what i was doing and they highly recommended that i go dual rear wheel over running them FWD powering each wheel seperately, they told me i would be fighting torque steer the entire time unless i run them through a single differential to combat the torque steer which is not possible with the build idea..

Now im trying to figure out how to properly mount the 2 so the load is equal on both as well i am learning about 3d printers now, i had a huge idea pop into my head recently when one of the bike guys i ride with occasionally showed up for a ride with a extremely light carbon fiber framed new bicycle using most of the hardware from his old bike.. he told me he built the whole thing on his 3d printer using a new carbon fiber plastic hybrid filament that is only $22 bucks a roll.

We had a lengthy talk about it since i was highly intrigued and i dont see him to often on the trails, but he said he printed it out in multiple peaces due to the limitations of his printer, but he printed it up so the main connections were all printed sections and when he assembled it all together the connections were mostly on straight sections...then afterwards he took some carbon fiber he bought from a company and went over the entire bike with an extra 2 layers adding extra support in the main connections areas, the printed parts had very minimal fill to them, they were just hallow for the most part lego parts used to shape the body to wrap the carbon fiber around... I really liked the idea and thought i could use this idea on my motorcycle build along with pvc for the longer pipe sections, since carbon fiber weave has dropped a lot in price and is actually very affordable, the actual epoxy is the more expensive part now of doing it from what im reading now.. I just thought it was an awesome way of going about building a frame, because he did it for a fraction of what it would have cost to buy a carbon fiber bike and he gained a 3d printer out of the deal that he wanted anyways and now has something he can say he built from scratch....


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## dcb (Dec 5, 2009)

that sounds like a decent set of motors for that application, did they give you any gearing suggestions (ratios, mechanical setup, i.e. motor in the middle w/two sprockets, or opposed motors, or??)?


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## Tomdb (Jan 28, 2013)

You could runt hem both on one output shaft, got keyways, depending on the width available this is a good option. 

So a single shaft where the motors plug onto each end. Ofcourse with the sprocket on the shaft.


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## hmincr (Jan 20, 2012)

Storx, where are you located in Fl ? I try to get up there once each year to visit family, in the Vero-Sebastian area. I would like to meet up sometime, if you are willing. I am planning a leaning Tadpole all electric down here and would enjoy meeting-seeing-conversing. 

PM me if you like. 

Thanks, Harold in Costa Rica


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