# Potential of QS 180 90H

#### GrantMorgan

##### 10 µW
Hey guys,

I’m currently in the end stages of planning for my motorcycle build and just wanted to see if anyone’s tested the limits of the QS180 90H. My pack is 115V and peak output (for 10 sec) is 1,200A and 400A continuous. Controller will be a Fardriver 1081800. Goal of this build is to reach speeds of at least 130MPH. Is the motor capable of this level of performance, and if not would you guys have a better recommendation?

Thank you,
Grant

What is the kv of the motor?

What is the kv of the motor?
I’m not able to find it on their spec sheet, but at it’s rated voltage (72V) it’s unloaded RPM is 4,100.

Many inrunner motors can only handle around 5000rpm, so you should check with QSmotors to see about that---beyond their limit (whatever taht is), they can begin to mechanically disintegrate. If it's rated to spin at 4100 at 72v, then it would be at around 6500rpm at full throttle on 115v. (115 / 72 x 4100)

Also, have you already calculated the power required to do the speeds you are after, under the specific riding conditions you'll be doing it under? If so, is the motor, battery, and controller capable of supplying that power for the length of time you'll need? Most motors can take at least twice their "rated" power for short bursts, and longer if they are properly cooled.

Many inrunner motors can only handle around 5000rpm, so you should check with QSmotors to see about that---beyond their limit (whatever taht is), they can begin to mechanically disintegrate. If it's rated to spin at 4100 at 72v, then it would be at around 6500rpm at full throttle on 115v. (115 / 72 x 4100)

Also, have you already calculated the power required to do the speeds you are after, under the specific riding conditions you'll be doing it under? If so, is the motor, battery, and controller capable of supplying that power for the length of time you'll need? Most motors can take at least twice their "rated" power for short bursts, and longer if they are properly cooled.
The controller is adequate for the application since I’m going to be well under its limits 99% of the time. The battery is definitely capable, I’ve seen tests of the cells where they were pulling for the equivalent of 600A for a good 15 minutes before they warmed up by any considerable, which in my build would be driving 69kW to the motor. The battery is a 17kWh 36s-2p pack composed of Japanese made LiFePo4 cells, and at peak output can deliver 138kW for 10 seconds. The motor in my mind currently is the weakest link, and I’m just trying to see how far people have pushed it. I’m not looking to cruise at speeds faster than 100, I just want to be able to hit higher for a moment for the fun of it. And I’ll be rigging up a water cooling system to at least cool through the exterior of the motor so I’m hoping that helps as well. All in all compared to the Zero SR/S it’s a considerably more powerful build and that bike is capable of reaching 124MPH, so if the QS180 is capable, I have no doubt in my mind of surpassing that. Also, If you guys know of a motor that’s more powerful available to the consumer market, I’d like to look into that as well. Thanks for the replies btw

IIRC at least osme of the Zero motors were kevlar (?) wrapped to prevent self-disassembly at high RPMs. Whether the QSmotor can handle the high RPM you'd be asking of it you'd have to ask QSmotors; I didn't find any posts here with anyone doing that.

(of course you can gear it for higher speed at the wheel wiht lower motor rpm, but you lose low end torque that way)

IIRC at least osme of the Zero motors were kevlar (?) wrapped to prevent self-disassembly at high RPMs. Whether the QSmotor can handle the high RPM you'd be asking of it you'd have to ask QSmotors; I didn't find any posts here with anyone doing that.

(of course you can gear it for higher speed at the wheel wiht lower motor rpm, but you lose low end torque that way)
Might sound crazy, but is there any reason I couldn’t make my 2p pack a 3p to supply more current, and just run two of the 180’s and have them both geared for higher speed to make up for the torque?

Other than the extra volume and weight the extra motor and controller would take up, and their cost, that should work easily enough.

(assuming that at the required gearing the torque of a single one isn't enough)

--assuming they both run the same wheel via the same chain or belt), they may run better if you can make sure the shafts/rotors of both line up exactly the same so the separate controllers that drive each one are better able to apply current the same way at the same time. Depending on the controllers they may run fine regardless.

What is the kv of the motor?
I think it is about 60, maybe slightly lower like 58 if I remember correctly.

I think the QS180 has HUGE potential. Honestly suprised more people dont mess with them. There's a video of some guys I think from Thailand that built a drag bike and the information I was able to get out of them was 108v and 1000 amps.
EDIT: Found the video, looks like it ran a 10.2 at 125 mph in the 1/4 mile :O. That would be cool if they came out with a water cooled version..

I'm looking to build similar to you here with a QS180. Only just started so I can't give you any insight into peak power. I was looking at the fardriver you mentioned but presently I'm leaning towards the cl1000 3shul after seeing the price for the fardriver.

I think the QS180 has HUGE potential. Honestly suprised more people dont mess with them. There's a video of some guys I think from Thailand that built a drag bike and the information I was able to get out of them was 108v and 1000 amps.
EDIT: Found the video, looks like it ran a 10.2 at 125 mph in the 1/4 mile :O. That would be cool if they came out with a water cooled version..
Interesting, in that video they claim they are running the QS180 at 105KW 96V for drag racing, which is 13 times its rated power.

Since a drag race is very short, maybe it works for the race length if they have some external way of cooling it down afterward (so the heat doesn't damage the magnets, sensors, or insulation, and so they can run more races soon afterward).

Or maybe they keep spare motors with them so when they bake one they can swap it out....