Anyone tried a MY1020 scooter motor instead of RC motors ?

[Jeff23spl]

I did read and watch some of what have done yet and it is mostly with RC motors at high speed dealing with RC stuff issues.

I was wondering if anyone would have used a different route with a biffer motor. I played a bit with kick scooters/ebike and larger BLDC motors. Yes it doesn't spin fast enough to run direct drive a turbine wheel but, what about having it mated to an overdrive belt and pulley?

KUNRAY MY1020 48V 72V 3000W 2000W Brushless Motor with Temperature Sensor for Electeic Bike Scooter Go Karts Fardrive Controller

【High Speed Motor】 MY1020 motor with 6 mm phase wires, internal temperature sensor. 3000W Motor Max Speed is 6700RPM. 【 Fardrive ND2260 】 Sine Wave Controller Programmable, voltage 48-72V, rated power: 3KW, Max DC Current 80A, phase current 260A. 【Pure Copper Coil】High conductivity, high...

cnkunray.com

Or if not enough https://cnkunray.com/products/kr5v

Different from RC specs, those motors are tested to run continuously at the advertised power and some run them at 2-4x past their rated power.
The cheapest one could probably run burst of 7-8kw at up to 7-8000rpm. I could probably get the rotor balanced to get it past it's max RPM design.
those are also already designed for lateral load from a drive system with room for vibration and abuse.

The controllers that goes with it work with a 0-5v throttle signal and has some safety features to accept more abuse. I think about a possible pedal throttle right below the gas pedal, to match turbine flow to engine load.

What about mating one to a P2 blower using a 4:1 pulley ratio? is it a realistic project ? I did read that it comes with a 18t pulley, i would need about 72t on the motor with a special machining to make it fit but since it is larger, i should not have issues for a larger shaft size.

 

[r.brown.bayliss]

Would need to be more like 1 to 6 or 1 to 8 ratio I think. So that increase the load a lot. I expect it will suffer from inertia, they look quite large, so they wont spin up quickly and being geared 1 to 6 or 8 will be slow, basically they will be laggy. Think of it like an old 10 speed push bike and trying to start off in 10th vs 2nd or 3rd gears.

 

[Jeff23spl]

Would need to be more like 1 to 6 or 1 to 8 ratio I think. So that increase the load a lot. I expect it will suffer from inertia, they look quite large, so they wont spin up quickly and being geared 1 to 6 or 8 will be slow, basically they will be laggy. Think of it like an old 10 speed push bike and trying to start off in 10th vs 2nd or 3rd gears.

The 4:1 comes from running the my1020 at 7-8000rpm to get 28-32k rpm at the blower.
In that case, the motor rpm limit is mechanical (rotor and bearing said limits from peoples testing it to destruction) but i can increase the electric rotating field to compensate for magnetic slippage (Erpm vs real rpm). voltage can easily be increased with those setup or even field weakening be used to boost rpm with better controller.
Im not planning to get the blower any faster than 30k rpm when i check the flow map, I'm more afraid of surging it than not having enough flow for my 155hp asthmatic 2.0l. (I know i would better use a smaller compressor wheel but the P2 remain easier to adapt than a turbo for my limited machining skills...i'm evaluating that option)

For gearing and load, i do agree but on the other side, a slower motor of same power make more torque to move more mass at lower speed. It will probably be less efficient but the extra torque should compensate for the extra load at some point.
The other motivation is because i already have 2 motor and controllers that i can re-use from other electric conversion projects vs buying rc stuff. And i am familiar with those compared to RC, i can replace the fets for a couple $ if i burn it while ESC surface mount need more skills and tools to work with.

 

[r.brown.bayliss]

The other motivation is because i already have 2 motor and controllers that i can re-use from other electric conversion projects vs buying rc stuff. And i am familiar with those compared to RC, i can replace the fets for a couple $ if i burn it while ESC surface mount need more skills and tools to work with.

That is a perfectly good reason to give it a shot

 

[gruntguru]

The max power of the motor is a key metric. 7 or 8 KW is not enough to make useful boost on anything bigger than a minicar engine.

 

[Jeff23spl]

The max power of the motor is a key metric. 7 or 8 KW is not enough to make useful boost on anything bigger than a minicar engine.

What would be the peak power needed to make some street boost on a 155hp 2l engine?

I used references from TorqAmp dynos and Alex tests. The first claiming 5kw and i remember some Alex tests in the 20kw range (+/-50v 400a)
I would like a little more flow than TorqAmp for more top end rpm boost but i don't need Alex capacity for drag racing a v8...This is how i though about 7-8kw....???

But this make me think again and i will probably need more power because more drive losses for the P2 and on my engine, it will need a bypass valve to avoid surge meaning i will need equivalent power of running it into a larger engine....

There is not much peak power test done on the MY1020 because it is mostly used for rides that need continuous power and the rating is made accordingly. The design is similar to RC motor with everything looking bigger...I feel positive that giving it more amps will brings more torque and more power. I will have to test it....

Here are some internal pictures and a video of this motor.

 

[r.brown.bayliss]

how will you be gearing it to get the impeller rpm needed?

 

[r.brown.bayliss]

The 4:1 comes from running the my1020 at 7-8000rpm to get 28-32k rpm at the blower.

Hi, i found this earlier and I thought it might interest you, the are T5 pulleys made to bolt to a crank and dive the P2, but they are geared to drive it at crankshaft 7000rpm, which is where your scooter motor rpms are.

P2 Supercharger T5 COG Pulley | Hyde Motor Works Shop

T5 COG Supercharger Drive pulley For Speedmaster P2 Centrifugal Supercharger Head Units. COG pulley made by Hyde Motor Works.

hydemotorworks.com

 

[r.brown.bayliss]

I notice that page recommends upgrading the P2 bearings as well

 

[Jeff23spl]

Yes i was looking at some Chinese pulley to do that on T5 format....i found some that would fit a 8-10-12mm shaft.
The motor shaft is machined with 2 flat side, i may get a small hole and figure out something to make the flat...And then i will have to make the braket and shims to get the belt aligned.

The P2 at way lower rpm seem an easier achievement for an electronic tech like me....(My machining tool is a grinder...)
I have in hands some used k04 turbo with 56mm wheels but it would need to spin above 100k rpm to work and according to chatgpt, the belt speed to do this would self destroy even if i get the best belt out there...Bearings to hold it would be another challenge.
A 3071/3076 copied Garret turbo would be a better match to my 2l but still need 2-3 stage to increase speed to 60-70k rpm unless i would use gears....

 

[maticulus]

Yes i was looking at some Chinese pulley to do that on T5 format....i found some that would fit a 8-10-12mm shaft.
The motor shaft is machined with 2 flat side, i may get a small hole and figure out something to make the flat...And then i will have to make the braket and shims to get the belt aligned.

The P2 at way lower rpm seem an easier achievement for an electronic tech like me....(My machining tool is a grinder...)
I have in hands some used k04 turbo with 56mm wheels but it would need to spin above 100k rpm to work and according to chatgpt, the belt speed to do this would self destroy even if i get the best belt out there...Bearings to hold it would be another challenge.
A 3071/3076 copied Garret turbo would be a better match to my 2l but still need 2-3 stage to increase speed to 60-70k rpm unless i would use gears....

Although a larger compressor wheel permits lower rpm speeds to achieve the desired boost pressure, theoretically the energy input needed is the same, whether it's the stress exerted on the belt of turning at high rpm, or the stress exerted on the belt in the form of increased tension at a lower rpm that accompanies a small wheel with a high gear ratio. The determining limits are mainly with the motor output but the load placed on the belt pretty much the same, just a transformation between high rpm stress and low rpm with high gear ratio stress depending on the route taken.

 

[gruntguru]

Compressor power requirement can be estimated using Matchbot. Once you get familiar with Matchbot you can enter values from the engine and your compressor map (doesn't need to be one of the Borg Warner maps). "Turbo Shaft Power" can be found in the "Calculated Outputs" section.

The default 2 litre 4 cylinder with 17 psi at 7,000 rpm has compressor power requirement of 47 hp.
If you change the boost at 6,000 rpm to 5 psi, the compressor power drops to 9 hp and the engine power is 216.8 hp.

 

[maticulus]

Compressor power requirement can be estimated using Matchbot. Once you get familiar with Matchbot you can enter values from the engine and your compressor map (doesn't need to be one of the Borg Warner maps). "Turbo Shaft Power" can be found in the "Calculated Outputs" section.

The default 2 litre 4 cylinder with 17 psi at 7,000 rpm has compressor power requirement of 47 hp.
If you change the boost at 6,000 rpm to 5 psi, the compressor power drops to 9 hp and the engine power is 216.8 hp.

I'm pretty familiar with it and have used it quite a bit. My curiosity is with the accuracy of the power requirement for the compressor. The bot specs are for a traditional turbo powered by exhaust gases. Did Borg do bench tests of the compressor power requirement to arrive at the provided values, or did they use a real time application with a turbo bolted to a test mule to document their efficiencies and in essence skew our estimated electrical power requirements on the high side.

 

[gruntguru]

I'm pretty familiar with it and have used it quite a bit. My curiosity is with the accuracy of the power requirement for the compressor. The bot specs are for a traditional turbo powered by exhaust gases. Did Borg do bench tests of the compressor power requirement to arrive at the provided values, or did they use a real time application with a turbo bolted to a test mule to document their efficiencies and in essence skew our estimated electrical power requirements on the high side.

The number is shaft power to drive the compressor. When you look at a compressor map from someone like BW you are looking at the result of extensive bench testing of the compressor alone - driven by an electric motor. Measuring compressor shaft power is absolutely part of that testing even though power is not plotted on the map.

However, Matchbot does not use these test results to determine compressor power - it doesn't even assume a BW compressor map. The power is identical to the thermodynamic power calculated from pressure, flow rate and efficiency. Matchbot uses this method to calculate compressor power. You can change pressure, flow and efficiency inputs and see the change in compressor power.

 

[Jeff23spl]

Although a larger compressor wheel permits lower rpm speeds to achieve the desired boost pressure, theoretically the energy input needed is the same, whether it's the stress exerted on the belt of turning at high rpm, or the stress exerted on the belt in the form of increased tension at a lower rpm that accompanies a small wheel with a high gear ratio. The determining limits are mainly with the motor output but the load placed on the belt pretty much the same, just a transformation between high rpm stress and low rpm with high gear ratio stress depending on the route taken.

The extra power i was referring above this post was not about larger wheel vs small ones, but first, because I was comparing the 5kw direct drive to the belt driven system. The belt and extra bearing add parasitic losses (Not much, but some) And second, because the P2 wheel is too large for a 2l engine. i will need to bypass some flow that will become wasted motor power. At mid rpm near full throttle (where people usually want the boost to start) it would run the blower into the surge limit of the map even at the lowest blower rpm. And at higher engine rpm i will remain close....Think about a small pipe returning some boosted flow into the blower inlet to stay out of surge. (Or a pipe leak but i cannot blow off because the skyactive-G use a Maf to control AFR and timing) ...This sound weird but the reduced blower efficiency will just need more electric power since i will remain far from blower maximum capacity, i will be electrically limited first but i don't see other options to match the P2 to my engine.

 

[Jeff23spl]

Compressor power requirement can be estimated using Matchbot. Once you get familiar with Matchbot you can enter values from the engine and your compressor map (doesn't need to be one of the Borg Warner maps). "Turbo Shaft Power" can be found in the "Calculated Outputs" section.

The default 2 litre 4 cylinder with 17 psi at 7,000 rpm has compressor power requirement of 47 hp.
If you change the boost at 6,000 rpm to 5 psi, the compressor power drops to 9 hp and the engine power is 216.8 hp.

It's an interresting tool, i was about to ask where/how you figure out engine VE and other parameters but i found the help text with the ? bulb...

I can clearly see with this that i will remain on flow surge zone of the P2 below 5000rpm, i will try to figure out how i can simulate the bypassed flow to estimate the extra power needed for the +/-50cfm loss....

 

[maticulus]

The extra power i was referring above this post was not about larger wheel vs small ones, but first, because I was comparing the 5kw direct drive to the belt driven system. The belt and extra bearing add parasitic losses (Not much, but some) And second, because the P2 wheel is too large for a 2l engine. i will need to bypass some flow that will become wasted motor power. At mid rpm near full throttle (where people usually want the boost to start) it would run the blower into the surge limit of the map even at the lowest blower rpm. And at higher engine rpm i will remain close....Think about a small pipe returning some boosted flow into the blower inlet to stay out of surge. (Or a pipe leak but i cannot blow off because the skyactive-G use a Maf to control AFR and timing) ...This sound weird but the reduced blower efficiency will just need more electric power since i will remain far from blower maximum capacity, i will be electrically limited first but i don't see other options to match the P2 to my engine.

This points out the boutique nature of this subject. In order to exercise full access to the possibilities and specifics in the exact details needed for your project, you need to have a lathe and a mill so that you can tailor your application. The P2 is highly convenient, except in your situation where you're trying to bridge a gap between demand and supply. Were not for the need of such specialized equipment, I'm sure the forum would be much busier. Having this equipment has helped me understand much better how laborious machining work can be, especially for custom parts.

 

[gruntguru]

The extra power i was referring above this post was not about larger wheel vs small ones, but first, because I was comparing the 5kw direct drive to the belt driven system. The belt and extra bearing add parasitic losses (Not much, but some) And second, because the P2 wheel is too large for a 2l engine. i will need to bypass some flow that will become wasted motor power. At mid rpm near full throttle (where people usually want the boost to start) it would run the blower into the surge limit of the map even at the lowest blower rpm. And at higher engine rpm i will remain close....Think about a small pipe returning some boosted flow into the blower inlet to stay out of surge. (Or a pipe leak but i cannot blow off because the skyactive-G use a Maf to control AFR and timing) ...This sound weird but the reduced blower efficiency will just need more electric power since i will remain far from blower maximum capacity, i will be electrically limited first but i don't see other options to match the P2 to my engine.

Perhaps you should look for a smaller compressor. Since you are already using a step-up drive, you can consider smaller tip-diameter wheels that need higher rpm for your boost goal. You can buy a wheel like this - Holset Low flow Wheel - and get a machine shop to carve out a turbo compressor housing to fit it. Characteristics of suitable wheels are:
1. Small inducer diameter (low flow)
2. Small tip height (low flow)
3. Large tip diameter (low rpm for a given boost)