QS 205

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ebike11   100 kW

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QS 205

Post by ebike11 » Jun 13 2019 6:57am

Hi there
I currently have a mxus 3000 3T but i only read great things about the QS 205. I think i only have room for the 50H model. I have a couple of quick questions.
Is 3T the lowest/fastest motor they sell?
Would there be quite a noticable difference compared to the mxus if both are using the same controller, Sabvoton 72200 and with 92V hot off the charger.
I wasted so much money on experimenting with so many controllers so im hoping to select the correct motor to give me more top speed on flats than the mxus. I love the mxus but..
Thanks

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MadRhino   100 GW

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Re: QS 205

Post by MadRhino » Jun 13 2019 11:35am

I don’t know the kv of your mxus, but the Qs205 50H is available 17.7 kv, making 1275 RPM at 72v. It will run with any sinewave controller.
Make it fool-proof, and I will make a better fool.
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ebike11   100 kW

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Re: QS 205

Post by ebike11 » Jun 13 2019 3:40pm

MadRhino wrote:
Jun 13 2019 11:35am
I don’t know the kv of your mxus, but the Qs205 50H is available 17.7 kv, making 1275 RPM at 72v. It will run with any sinewave controller.
Thx!. Ill check the mxus kv..
Would you know if the 3T is the fastest version they make?

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MadRhino   100 GW

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Re: QS 205

Post by MadRhino » Jun 13 2019 4:35pm

I believe MXUS is offering only one version of 3T winding. It is their fastest motor but I don’t know its Kv. All I know is that I leave it in the dust with my commuter that has a QS 205, not even the fastest Kv QS does make.

The MXUS 3kw is built better than a QS 205 though, but the heavier QS 205 can shed more heat, thus can be fed more power. If your MXUS was wound faster, it would overheat quicker because of its light weight. Until we have motors that are made to fit liquid cooling, motor weight can’t be cut without loosing some reliability in acceleration performance.
Last edited by MadRhino on Jun 13 2019 4:39pm, edited 2 times in total.
Make it fool-proof, and I will make a better fool.
Current bikes
Street: https://s20.postimg.org/ewrvugywt/Session_04_2015.jpg
Dirt: https://s20.postimg.org/lbqwr55ml/IMG_0157.jpg

litespeed   100 kW

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Re: QS 205

Post by litespeed » Jun 13 2019 4:37pm

https://endless-sphere.com/forums/viewtopic.php?t=65972

3T- is fastest wind as shown in the first post. I believe they WILL do a custom wind if you wanna pay for it. KV is 17.71.

Tom
I'm married so you know I'm no stranger to pain!

ebike11   100 kW

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Re: QS 205

Post by ebike11 » Jun 13 2019 6:44pm

litespeed wrote:
Jun 13 2019 4:37pm
https://endless-sphere.com/forums/viewtopic.php?t=65972

3T- is fastest wind as shown in the first post. I believe they WILL do a custom wind if you wanna pay for it. KV is 17.71.

Tom
Thanks!

ebike11   100 kW

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Re: QS 205

Post by ebike11 » Jun 13 2019 6:45pm

MadRhino wrote:
Jun 13 2019 4:35pm
I believe MXUS is offering only one version of 3T winding. It is their fastest motor but I don’t know its Kv. All I know is that I leave it in the dust with my commuter that has a QS 205, not even the fastest Kv QS does make.

The MXUS 3kw is built better than a QS 205 though, but the heavier QS 205 can shed more heat, thus can be fed more power. If your MXUS was wound faster, it would overheat quicker because of its light weight. Until we have motors that are made to fit liquid cooling, motor weight can’t be cut without loosing some reliability in acceleration performance.
Thanks for the info!
Which kv model of the 205 do you have?

litespeed   100 kW

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Re: QS 205

Post by litespeed » Jun 13 2019 7:50pm

I know you didn’t ask but I have a 3.5T which is 14.41 KV.....my bike will go well past 65mph on 20s.

Tom
I'm married so you know I'm no stranger to pain!

ebike11   100 kW

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Re: QS 205

Post by ebike11 » Jun 13 2019 8:00pm

litespeed wrote:
Jun 13 2019 7:50pm
I know you didn’t ask but I have a 3.5T which is 14.41 KV.....my bike will go well past 65mph on 20s.

Tom
Thanks as well
Would you happed to know the axle size of the 205 for torque arms? I know the mxus M16

litespeed   100 kW

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Re: QS 205

Post by litespeed » Jun 13 2019 8:54pm

I'm married so you know I'm no stranger to pain!

ebike11   100 kW

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Re: QS 205

Post by ebike11 » Jun 13 2019 9:31pm

litespeed wrote:
Jun 13 2019 8:54pm
16mm with 10mm flats.

https://endless-sphere.com/forums/downl ... ?id=201606

Tom
Thanks..i didnt see that
What controller are u using?

markz   100 GW

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Re: QS 205

Post by markz » Jun 13 2019 10:28pm

All I know, from reading the forums, is that once you start getting down to the 2T and 1T (If thats possible), there becomes problems in controlling the motor. Perhaps its something to do with back EMF, but I really have no clue. I have the MXUS 3kw 4T, not because I wanted to go super fast, but because I wanted hill climbing power by lacing motor into a smaller wheel, getting more torque, faster take offs, up to speed faster.

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ridethelightning   1 MW

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Re: QS 205

Post by ridethelightning » Jun 14 2019 4:51am

MadRhino wrote:
Jun 13 2019 4:35pm
The MXUS 3kw is built better than a QS 205 though, but the heavier QS 205 can shed more heat, thus can be fed more power.
can you add more details about why you like the mxus build please, im curious :D

i only have an old pressed steel stator v2mxus, im not that impressed by it..

litespeed   100 kW

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Re: QS 205

Post by litespeed » Jun 14 2019 6:22am

ebike11 wrote:
Jun 13 2019 9:31pm
litespeed wrote:
Jun 13 2019 8:54pm
16mm with 10mm flats.

https://endless-sphere.com/forums/downl ... ?id=201606

Tom
Thanks..i didnt see that
What controller are u using?
I use a MaxE.
I'm married so you know I'm no stranger to pain!

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MadRhino   100 GW

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Re: QS 205

Post by MadRhino » Jun 14 2019 9:35am

ridethelightning wrote:
Jun 14 2019 4:51am
MadRhino wrote:
Jun 13 2019 4:35pm
The MXUS 3kw is built better than a QS 205 though, but the heavier QS 205 can shed more heat, thus can be fed more power.
can you add more details about why you like the mxus build please, im curious :D

i only have an old pressed steel stator v2mxus, im not that impressed by it..
I see. I was talking about the newer MXUS. Still, I find that QS are making their motors powerful with lots of copper, but they really don’t care about the improvement in material and machining precision. They are the old standard Chinese hub, only bigger.

Yet, their biggest motors are now offered with liquid cooling, so we can hope that a liquid cooled 205 is possible in a near future. With cooling implemented, the next step is the use of light weight materials and higher precision standards. The future of the DD hub is easy to see, but long to come. I guess we will have to wait another decade, before we can buy big DD hubs made with ceramic and carbon composites,
Switching winding, regulated temp... Half the weight.
Make it fool-proof, and I will make a better fool.
Current bikes
Street: https://s20.postimg.org/ewrvugywt/Session_04_2015.jpg
Dirt: https://s20.postimg.org/lbqwr55ml/IMG_0157.jpg

j bjork   100 W

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Re: QS 205

Post by j bjork » Jun 16 2019 10:48am

As you can see on their website 3T is 16.32kv, but there are a 3T- with 17.71kv.
http://www.cnqsmotor.com/en/article_rea ... r/536.html

I have a 4T, and my bike does 80km/h on 20s with 17" moped wheel. Probably a bit more if I keep my head down and try on a longer strait.

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