serious_sam
10 kW
Very true.markz said:
Mxus 3k vs Qs205
- Thread starter eCruiser3k
- Start date
j bjork
1 MW
I have a qs 205 50H v3 4t.
http://www.cnqsmotor.com/en/article_read/QS%20QSMOTOR%20350W%20-%203000%20Watt%20Peak%2014kW%20205%2050H%20V3%20Brushless%20DC%20electric%20bike%20ebike%20hub%20motor/536.html
Down the page are kv for different winds etc.
It is not very hilly around here, I drive mostly in the woods. Yes, it probably is a very short peak. I think I usually se numbers in the 20-22kw range (peak) after a ride.
http://www.cnqsmotor.com/en/article_read/QS%20QSMOTOR%20350W%20-%203000%20Watt%20Peak%2014kW%20205%2050H%20V3%20Brushless%20DC%20electric%20bike%20ebike%20hub%20motor/536.html
Down the page are kv for different winds etc.
It is not very hilly around here, I drive mostly in the woods. Yes, it probably is a very short peak. I think I usually se numbers in the 20-22kw range (peak) after a ride.
j bjork...Thanks for the link to the Kv numbers :wink: .
eCruiser3k...What did you end up doing?
I came back to this thread after a while because I did a lot of research and my conclusion was it comes down to a MXUS with the 45mm stator or the QS 205 V3 with the 50mm stator just like "eCruiser3k" started out with when he started this discussion
.
From what I have been able to find, the QS has a little more copper fill/mass so it should handle higher amperage...remember it is the amperage that heats a motor not voltage. Voltage is just the force pushing the amps so if you want to talk overheating, watts can be a little misleading. The QS also has larger phase wires leading to the motor so they can handle higher amperage. I think I'd go with the QS205 but there are a lot of variables to consider. One of the biggest variables is how wide are your dropouts...the MXUS is 142mm wide and the QS205 is 154mm...you can flex a steel frame some but an aluminum frame should not be flexed as much.
A couple tid bits...an electric motor puts out max torque at zero rpms and max power at about 50% of the full speed rpm. So if you want to accelerate from 0-50 as quickly as possible, a Kv that gives you a max speed over 50 mph would be the way to go. The Grin Tech "Trip Simulator" can calculate the time required to go from 0-50 mph...although you might have to back into it indirectly. It would be a good way to compare two motors IMO but the Motor Simulator is a lot quicker and easier for a comparison. Somebody mentioned a smaller diameter wheel/tire...IMO a higher Kv with a smaller diameter tire works better than the other way around for acceleration and to prevent over heating.
My problem is I am a weight weenie and things start to get heavy fast when you want to increase acceleration with a DD motor...you need more battery to supply higher amperage, a bigger controller to handle the amperage, and a larger diameter and wider motor to supply more torque so I keep coming back to the MAC which produces more peak torque per battery amp than ANY ebike motor . Only drawback on the MAC is it will overheat if you want to ride over about 30 mph or if you feed it high amperage and continually stop/start. The gears and the clutch hold up just fine...mine puts out ~190 NM with 60A battery supply and the QS205 puts out ~150 NM with the same battery amperage.
Someone asked about the accuracy of the Grin Tech Motor Simulator...it is extremely accurate and only limited by how accurately the data is that you enter BUT it does not account for saturation.
eCruiser3k...What did you end up doing?
I came back to this thread after a while because I did a lot of research and my conclusion was it comes down to a MXUS with the 45mm stator or the QS 205 V3 with the 50mm stator just like "eCruiser3k" started out with when he started this discussion
.From what I have been able to find, the QS has a little more copper fill/mass so it should handle higher amperage...remember it is the amperage that heats a motor not voltage. Voltage is just the force pushing the amps so if you want to talk overheating, watts can be a little misleading. The QS also has larger phase wires leading to the motor so they can handle higher amperage. I think I'd go with the QS205 but there are a lot of variables to consider. One of the biggest variables is how wide are your dropouts...the MXUS is 142mm wide and the QS205 is 154mm...you can flex a steel frame some but an aluminum frame should not be flexed as much.
A couple tid bits...an electric motor puts out max torque at zero rpms and max power at about 50% of the full speed rpm. So if you want to accelerate from 0-50 as quickly as possible, a Kv that gives you a max speed over 50 mph would be the way to go. The Grin Tech "Trip Simulator" can calculate the time required to go from 0-50 mph...although you might have to back into it indirectly. It would be a good way to compare two motors IMO but the Motor Simulator is a lot quicker and easier for a comparison. Somebody mentioned a smaller diameter wheel/tire...IMO a higher Kv with a smaller diameter tire works better than the other way around for acceleration and to prevent over heating.
My problem is I am a weight weenie and things start to get heavy fast when you want to increase acceleration with a DD motor...you need more battery to supply higher amperage, a bigger controller to handle the amperage, and a larger diameter and wider motor to supply more torque so I keep coming back to the MAC which produces more peak torque per battery amp than ANY ebike motor
. Only drawback on the MAC is it will overheat if you want to ride over about 30 mph or if you feed it high amperage and continually stop/start. The gears and the clutch hold up just fine...mine puts out ~190 NM with 60A battery supply and the QS205 puts out ~150 NM with the same battery amperage.Someone asked about the accuracy of the Grin Tech Motor Simulator...it is extremely accurate and only limited by how accurately the data is that you enter
BUT it does not account for saturation.eCruiser3k
10 mW
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- May 4, 2019
- Messages
- 22
Hello, I haven't been here lately and it seems that there has been new discussion here so I apologize for the late reply.
My situation is that I have now QS205 4t with 24" fat rim. My earlier motor was Mxus 4t with 26" fat rim and acceleration from 0 to 70km/h was 7s and now 5s with QS205! So there is big improvement altough motors are same caliber. Battery and controller are the same, just little more current for 205 maybe +15a battery/40a phase (190a/440a). Those current changes was so little that I believe effect was actually almost nothing, I cant even notice it in my ass. And ebike simulator support that. But reason why acceleration was so much better was smaller rim of course and amout of current for Mxus, maybe it was so much that it could not handle that and then came 205 with better ability for current handling so it show in acceleration. This new 205 is also temperature limited and getting warm pretty quick even if it should be factory ferrofuided and only in street use. In the other hand it is possible that I have defined temperature settings wrong in Cycle Analyst because it is only getting little warm from outside even if CA shows example 100C degrees. How j bjork´s motor, is it getting hot from outside with big power?
Im thinking to buy front motor to get more accelaration, maybe Mac or Gmac and Phaserunner controller because of interesting features. 2wd is not ideal solution, it is more complex and prevent wheelies but almost only way for me to get more acceleration with limited battery and frame. I must try that "Trip Simulator" what Bullfrog said.
QS273 in dyno:
https://www.youtube.com/watch?v=5aSFXgQUqRQ
My situation is that I have now QS205 4t with 24" fat rim. My earlier motor was Mxus 4t with 26" fat rim and acceleration from 0 to 70km/h was 7s and now 5s with QS205! So there is big improvement altough motors are same caliber. Battery and controller are the same, just little more current for 205 maybe +15a battery/40a phase (190a/440a). Those current changes was so little that I believe effect was actually almost nothing, I cant even notice it in my ass. And ebike simulator support that. But reason why acceleration was so much better was smaller rim of course and amout of current for Mxus, maybe it was so much that it could not handle that and then came 205 with better ability for current handling so it show in acceleration. This new 205 is also temperature limited and getting warm pretty quick even if it should be factory ferrofuided and only in street use. In the other hand it is possible that I have defined temperature settings wrong in Cycle Analyst because it is only getting little warm from outside even if CA shows example 100C degrees. How j bjork´s motor, is it getting hot from outside with big power?
Im thinking to buy front motor to get more accelaration, maybe Mac or Gmac and Phaserunner controller because of interesting features. 2wd is not ideal solution, it is more complex and prevent wheelies but almost only way for me to get more acceleration with limited battery and frame. I must try that "Trip Simulator" what Bullfrog said.
QS273 in dyno:
https://www.youtube.com/watch?v=5aSFXgQUqRQ
eCruiser3k
10 mW
- Joined
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Yes I know that video but I haven't watched it yet, just little. Thats why I haven't bought the motor and controller yet because making it working good is not simply thing necessarily. I wish that I could drive daily/normal driving with rear motor only and front join in only when needed. Like you said earlier Mac motor like Gmac produce lot of torque and it is also light vs hub motors so it might be good in front if 2wd system and if kv´s is about same I dont see any problem. But I havent done it yet, this is only theoretical And if they get launched little different time their max current peak moment are not on top of each other which is easier for battery.
And if they get launched little different time their max current peak moment are not on top of each other which is easier for battery.eCruiser3k
10 mW
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Bullfrog, have you already purchased an motor?
j bjork
1 MW
eCruiser3k said:
No, from what I remember it gets about 50-55 degrees C on the magnet ring between the spokes when the tempreadings shows maybe 100-120 degrees C. Statoraid made a lot of difference in how much the motor can take before it get too hot. But not a very big difference in temp on the outside of the motor from what I can remember. I have 10ml in it.
eCruiser3k
10 mW
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j bjork said:
Thats good to know that it does not heat up a lot from the outside surface even if there is a statorade inside. Once I had Crystalyte front hub motor without statorade and what I remember it get quite hot from between the spokes after high speed run when I stopped and heat began to come to the outside surface. I also feel that my old Mxus 3k warmed little more from outside than my current Qs205. Both with ferro.
eCruiser3k
10 mW
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Bullfrog said:
Luckily you are here to tell that
Things can get pretty bad with motorcycle if there is bad luck.So you continue with MAC, is this new one also 5t?
The 5T I had custom made because I was going to attempt to set a speed record but it is still in the box and I never used it.
I had planned to install it in a 29" wheel and only run it for a few minutes at a time. If somebody wanted to use it in a 20" wheel, it would work great but I would not install it in anything bigger than a 20" wheel because it will run too hot.
I had planned to install it in a 29" wheel and only run it for a few minutes at a time. If somebody wanted to use it in a 20" wheel, it would work great but I would not install it in anything bigger than a 20" wheel because it will run too hot.
The Kv determines the rpm the motor wants to turn and is measured in rpms per volt. So a 12T MAC without any load will turn slower than a 10T MAC. With "T" being the number of times copper wire is wrapped around each pole of the stator...or proportional to the number of wraps in the case of some motors. Kv and T are inversely proportional.
All motors of a given design...i.e. MAC, QS205, MXUS 3K, etc. will produce the same torque per battery amp. So if you supply 40A from your battery to a 12T MAC and a 10T MAC they will both have the same torque. Different windings of a given motor will require more Phase current to produce the same amperage...i.e. a 10T MAC will require more phase amperage to produce the same torque as a 12T MAC but the battery amperage being supplied to the controller is the same.
Deleted info about my 5T MAC since I sold it.
Back to the topic of THIS thread...the MXUS and the QS205 being Direct Drive Hub Motors, they can handle higher power levels for longer periods of time without overheating and a very small amount of ATF or Ferro Fluid will bridge the small air gap between the stator and the hub so you can reject heat even better and run even more power continuously but they require more amperage to match the torque of a Geared Hub Motor so that can mean a bigger/more expensive controller and a bigger/more expensive battery and overall more weight. You should always match your motor selection to your requirements and higher power levels for longer periods of time are where the DD hub motors shine.
All motors of a given design...i.e. MAC, QS205, MXUS 3K, etc. will produce the same torque per battery amp. So if you supply 40A from your battery to a 12T MAC and a 10T MAC they will both have the same torque. Different windings of a given motor will require more Phase current to produce the same amperage...i.e. a 10T MAC will require more phase amperage to produce the same torque as a 12T MAC but the battery amperage being supplied to the controller is the same.
Deleted info about my 5T MAC since I sold it.
Back to the topic of THIS thread...the MXUS and the QS205 being Direct Drive Hub Motors, they can handle higher power levels for longer periods of time without overheating and a very small amount of ATF or Ferro Fluid will bridge the small air gap between the stator and the hub so you can reject heat even better and run even more power continuously but they require more amperage to match the torque of a Geared Hub Motor so that can mean a bigger/more expensive controller and a bigger/more expensive battery and overall more weight. You should always match your motor selection to your requirements and higher power levels for longer periods of time are where the DD hub motors shine.
Just a general comments and not directed toward anyone...
For ANY given motor design, the torque produced per battery amp is equal regardless of which winding you choose. Taken to an extreme, slower windings are usually battery amperage limited and faster windings are usually controller (phase) amperage limited as far as the torque they can deliver.
For ANY given motor design, the torque produced per battery amp is equal regardless of which winding you choose. Taken to an extreme, slower windings are usually battery amperage limited and faster windings are usually controller (phase) amperage limited as far as the torque they can deliver.
eCruiser3k said:
I decided to stick with my MAC motors...they are lighter, provide more acceleration per battery amp and don't require as big of a battery or controller as a Direct Drive motor. On the down side...the MAC/GMAC will over heat if you are not careful. The over heating limits you to roughly 30 mph or less only because going faster requires more amperage and increased amperage produces more heat.
I noticed some comments on rim/wheel sizes...remember motorcycle rims are specified based on the approximate rim diameter where bicycle rims are specified on the approximate outer diameter of the tire. My statement is based on diameters BEFORE fat tires were produced so it is not accurate regarding fat tire overall diameters.
Can anyone tell me where they purchased a "MXUS 3K Turbo" motor in the past few years?
I want to build an ebike using the MXUS motor since it is a little narrower and lighter than the QS205 and the Cromotor.
I have never purchased anything via Alibaba or Alibaba Express...if that is your source for the MXUS motor, please tell us how well the overall process worked.
Thank You
I want to build an ebike using the MXUS motor since it is a little narrower and lighter than the QS205 and the Cromotor.
I have never purchased anything via Alibaba or Alibaba Express...if that is your source for the MXUS motor, please tell us how well the overall process worked.
Thank You
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