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Motor options for sportbike conversion

Posted: Feb 19 2019 12:16am
by GigawattsCanada
Hello, I have a 1999 cbr600f4 and I would like to convert it to electric. I have been considering a few different motor options. ME1507 BLDC, HPEVS AC20, Agni 95R or a ME1003.

I would like the bike to have decent acceleration and a top speed of 160 kmph/100 mph or so.

What other motor options would be best suited for my bike ?

Re: Motor options for sportbike conversion

Posted: Feb 19 2019 2:56am
by Dui, ni shuo de dui
Hub motors:

QS 273:
http://www.qs-motor.com/product/17inch- ... otorcycle/

New QS 10000W:
http://www.qs-motor.com/product/new-100 ... -0x17-rim/

Pretty good motors who can handle way more power than they are rated for (successfully tested at 10 times their rated power)

Hub motors will save you a fair amount of space for more battery and they are not actually that much heavier than a regular wheel+chain+sprocket system. Main drawback is that you have no way to change the gear ratio.

Re: Motor options for sportbike conversion

Posted: Feb 19 2019 3:35am
by GigawattsCanada
Unfortunately these hub motors are only good for 130 kmph. I want faster, that's the reason I want to say with a frame mounted motor(s) to change the gear ratio.

Re: Motor options for sportbike conversion

Posted: Feb 19 2019 3:48am
by Dui, ni shuo de dui
GigawattsCanada wrote:
Feb 19 2019 3:35am
Unfortunately these hub motors are only good for 130 kmph. I want faster, that's the reason I want to say with a frame mounted motor(s) to change the gear ratio.
They can go way faster if you use flux weakening, no problem to reach 160 km/h.
Plus you can ask QS for a custom winding if you want.

Re: Motor options for sportbike conversion

Posted: Feb 19 2019 4:19am
by GigawattsCanada
OK I will look into those. 160 kmph or faster would be perfect.

Re: Motor options for sportbike conversion

Posted: Feb 19 2019 1:38pm
by GigawattsCanada
Any other options out there ?

Re: Motor options for sportbike conversion

Posted: Feb 19 2019 2:41pm
by MJSfoto1956
Besides mid-motor, there are some brave souls out there that have installed two hub motors (one in front, one in rear) giving you all-wheel drive and nearly double the HP.

M

Re: Motor options for sportbike conversion

Posted: Feb 19 2019 2:50pm
by skeetab5780

Re: Motor options for sportbike conversion

Posted: Feb 19 2019 5:10pm
by GigawattsCanada
The ME1507 with a good controller and lithium batteries would destroy those QS hub motors and I also want to have the option of gear ratio changes.

Re: Motor options for sportbike conversion

Posted: Feb 19 2019 5:12pm
by GigawattsCanada
MJSfoto1956 wrote:
Feb 19 2019 2:41pm
Besides mid-motor, there are some brave souls out there that have installed two hub motors (one in front, one in rear) giving you all-wheel drive and nearly double the HP.

M
No thanks lol.

Re: Motor options for sportbike conversion

Posted: Feb 19 2019 9:26pm
by Dui, ni shuo de dui
GigawattsCanada wrote:
Feb 19 2019 5:10pm
The ME1507 with a good controller and lithium batteries would destroy those QS hub motors
I would not be so sure of that.
Pretty sure it would be the opposite actually.
Just take a look at this thread: https://endless-sphere.com/forums/viewt ... 12&t=82155

Re: Motor options for sportbike conversion

Posted: Feb 20 2019 7:02pm
by GigawattsCanada
Interesting, just one draw back is I can't change the gear ratio.

Re: Motor options for sportbike conversion

Posted: Feb 20 2019 8:11pm
by Dui, ni shuo de dui
GigawattsCanada wrote:
Feb 20 2019 7:02pm
Interesting, just one draw back is I can't change the gear ratio.
You can by changing the tire size, but it might get expensive XD

That's indeed a drawback. But once you find the correct gear ratio on an inboard motor you rarely change it anyways.
On the other hand you'll have a lot more space for a lot more battery, so this is to be considered too.

Re: Motor options for sportbike conversion

Posted: Feb 20 2019 8:47pm
by jonescg
There are more powerful options out there, but they are also more expensive. Phi-Power have a great range.

Re: Motor options for sportbike conversion

Posted: Feb 20 2019 11:43pm
by GigawattsCanada
jonescg wrote:
Feb 20 2019 8:47pm
There are more powerful options out there, but they are also more expensive. Phi-Power have a great range.
I like the Phi27S, going to call them and see that controllers they recommend. Definitely the size I'm looking for.

Re: Motor options for sportbike conversion

Posted: Feb 21 2019 1:12am
by amberwolf
GigawattsCanada wrote:
Feb 20 2019 7:02pm
Interesting, just one draw back is I can't change the gear ratio.
You can effectively change it by changing the voltage of the system. If you need higher speeds, increase the system voltage (and potentially the current). Depending on the motor wind, it can shift the power band around.

See http://ebikes.ca/simulator and play with various motor controller battery combos to see how this may do what you want.

Re: Motor options for sportbike conversion

Posted: Feb 21 2019 2:17pm
by GigawattsCanada
amberwolf wrote:
Feb 21 2019 1:12am
GigawattsCanada wrote:
Feb 20 2019 7:02pm
Interesting, just one draw back is I can't change the gear ratio.
You can effectively change it by changing the voltage of the system. If you need higher speeds, increase the system voltage (and potentially the current). Depending on the motor wind, it can shift the power band around.
That is not gear ratio change, all that is doing is increasing the voltage.

Re: Motor options for sportbike conversion

Posted: Feb 21 2019 2:18pm
by GigawattsCanada
Changing the voltage is not going to change the gear ratio.

Re: Motor options for sportbike conversion

Posted: Feb 21 2019 9:27pm
by Dui, ni shuo de dui
GigawattsCanada wrote:
Feb 21 2019 2:18pm
Changing the voltage is not going to change the gear ratio.
It will accomplish exactly the same thing: increase torque while diminishing speed or increase speed while diminishing torque.
So it's not a ratio change if you want to get into the semantics, but in the end IRL it's just about the same.
Anyway, in practice it's hard to do because you'd had to rebuild your battery or change its configuration if it's modular. Just totally impractical.

Actually, now that I think about it and since you seem ready to consider gigantic motor options like a Phi27, you could totally buy a hub motor and convert it into an inboard motor. The only thing needed is a bit of lathe work to get rid of the rim (it can even be done by hand but a lathe is better, probably even possible to DIY a lathe using the motor itself as a power source). The big QS motors seem to be smaller in diameter than the Phi27, you can attach a sprocket instead of the brake disk (so you could do gear changes if you want) and essentially do the same thing. The advantages being that it would be much cheaper and a bit more compact. Just a thought.

I think you should mention your budget, as well as what you actually plan for your build. There are a lot of options when it comes to motors, but it will depend a lot wether you're ready to spend 500 bucks or 10 000.

Re: Motor options for sportbike conversion

Posted: Feb 21 2019 11:20pm
by Sunder
I'm converting a Ninja 250R.

Trying to get my hands on a QS 273 50H V3 - Rated for 8kw continuous, 23kw for up to 30 seconds, and they say that those figures are conservative. There are much larger versions that can do 14kw continuous.

This was my calculation sheet for the different winding options:
Options.jpg
Options.jpg (60.78 KiB) Viewed 1039 times
You can adjust the voltages of your own battery (assuming you haven't built it already), to get the ideal top speed trading off for torque.

I understand you want to get a variable gearing ratio during ride (so no changing tyres or voltages on the road), but if I can get a bike that has a top speed of 150km/h and has so much torque I can flip the bike on take off, where's the advantage? A marginally faster 110-150km/h?

If that is really important to you, because you want a great 1/4 mile time, then something with a 2 or 3 speed gearbox makes sense. But electric motors aren't like petrol motors. The maximum torque range is basically from stalled (0 rpm) all the way to about 80ish percent of max speed. The gains from a gearbox are very marginal. Why do you think Teslas (and in fact most electric cars) don't have one?

Re: Motor options for sportbike conversion

Posted: Mar 01 2019 12:32am
by GigawattsCanada
OK so I was considering the 14kw 17 inch hub motor but for $2000 ??

Re: Motor options for sportbike conversion

Posted: Mar 01 2019 12:39am
by GigawattsCanada
The ME1507 is $1000 and its continious rated power is 13kW, peak power 44kW (62hp) at 100 volts and max rpm of 8000 rpm.

For the price of that qs 14kw hub motor I could mount two of the ME1507 motors in the frame and run them in series or pararell and get 120 hp !!!

Re: Motor options for sportbike conversion

Posted: Mar 05 2019 1:32am
by atarijedi
Depends on how you want to set up the bike.

Do you want a mid-motor with sprockets and chains (or belts and pulleys like Zero). You have less space for batteries, a con, but also have less unsprung weight, a pro?

Or do you want a hub motor with no sprockets or chains, more space for batteries, but also more unsprung weight.

On a sportbike that will be on relatively smooth asphalt roads, unsprung weight shouldn't be as much of an issue.

Mobipus makes a 72V 600A controller, for around $1425AUD, you can get them via https://ballaratebikes.com/collections/controllers

They are awesome controllers, very robust, and include a feature you might like called automatic FOC. You read about people talking about field weakening, well one method to do that is called FOC (Field Oriented Control). The Mobipus can enable field weakening automatically when you hit a certain speed. So say the controller can only normally go up to 88V, and that gives you 130kph. You can set the controller so that when it detects the 128kph (based on motor RPM), than field weakening will be enabled and you can go up to 160kph.

Field weakening lowers efficiency quite a bit, which is why this automatic feature is handy. Obviously, it would be better to simply get a motor that can do 160kph with the battery pack voltage you have decided to use.

The QS273 80H V3, with its default winding for a Kv of 14.5 (rpm/V) can do 160kph, with a 24in outer diameter wheel, if you supply it 96V. That's under ideal unloaded conditions. I would ask them for a custom wind, with a higher Kv, some of their other motors have a Kv of 16.2 (88V for 160kph), 17.7 (79V for 160kph), and 19.99 (70V for 160kph).

Also, just to note, you can't run PMSMs in series or parallel, they each need their own controller.