MXUS coming out with a 5K-Turbo motor, 55mm Magnets

[Quokka]

Ok. Here is a simple question i hope to the guys that know their stuff. Is this mxus v5 an upgrade to a QS205? They weigh about the same, the mxus is 5mm wider- can i expect any difference in performance? Or would I be better iff with a QS273 40H. Will be running 90v on unlocked maxe with max amps i push down thing.

Dont want to buy this thing and be dissapointed, but at the same dont want to go machining my drop outs to fit 12mm flats if i dont need to

 

[SlowCo]

@Quokka,
Read the comment by Ohbse on the hub motor cooling thread:

Hey guys I am new to this so I wanted to ask some questions to get some know-how about ff. I have a QS V3 motor and also have ordered now 10ml ferrofluid 1110 from a german guy from this forum. He said it will reduce the heat about 40%. I have talked about this with some experienced guys in this and they have told me that it is unrealistic that 10 gram of liquit can cover 40% produced heat of a 45.000 gram heavy bike + 70.000 gram heavy rider.
Could you please explain me how the ff works / why it works?

FF effectively bridges the gap between the heat producing elements (windings) and the heat removing elements (Hub shell/covers). This dramatically increases ability to remove heat. 40% reduction in temperature is absolutely possible. What's more amazing as you could achieve that difference with only using half of your 10ml tube. This has been proven empirically and via experience of many, many people now running FF. The silent majority in this case are those that no longer have heat issues.

Offroader - you have invested more time thinking and writing about this topic than it deserves - buy some FF, install it and see for yourself the difference. It is *very* easy to remove, certainly compared to conventional oil cooling and takes mere moments to do compared with many of the other elaborate methods you have spent lots of time contemplating. The science is already done, see the thread title - definitive testing has been completed and it proved, definitively, that FF is an excellent solution.

Independently of the FF advancement, Sketch has come up with an excellent solution for the other side of the equation and has also definitively proven his hubsink solution dramatically improves cooling ability. If anybody running good quality FF and hubsinks mounted correctly still has heat issues then their controller is incorrectly configured or they are running a motor very inadequate for their requirements. a QS 50mm v3 with FF and hubsinks is capable of serious performance for extended periods of time, far, far in excess of what I could personally use despite being young fit and not afraid of breaking rules. At this end of the spectrum I do not believe there's really a problem left to solve, unless perhaps you're morbidly obese.

Here is the complete thread:
https://endless-sphere.com/forums/viewtopic.php?f=2&t=48753&start=1675

So if you already have a 50mm QS205 then FerroFluid and HubSinks might be a less expensive and involving method of upping the performance.

 

[Quokka]

Thanks Slo, I have my hubsinks on 1 bike already -QS205 . Still waiting on Ff to fill it up.

 

[Samd]

Ok. Here is a simple question i hope to the guys that know their stuff. Is this mxus v5 an upgrade to a QS205? They weigh about the same, the mxus is 5mm wider- can i expect any difference in performance? Or would I be better iff with a QS273 40H. Will be running 90v on unlocked maxe with max amps i push down thing.

Dont want to buy this thing and be dissapointed, but at the same dont want to go machining my drop outs to fit 12mm flats if i dont need to

Yep ten percent more stator width = linear increase in torque per amp.
Copper fill percentage is unknown. Its also a major factor. The QS guys loaded copper into the v3.

But the step up to a 9" stator radius seems to be going largely unnoticed. Torque is about proportional per amp to the square of the radius.

QS also make the 260mm and 273mm stator motors with a bike axle IIRC> up to maybe 40mm stator width to fit a brake.

My QS273 moto weighs 22kg. There's a point where you have to pull up an ever increasing size for a given riding style of course.

 

[markz]

The MXUS 55 will be the same as the QS

 

[Rix]

My QS273 moto weighs 22kg.

DAMN, thats alot of copper!

 

[Blue Ice Bike]

This seems like a great motor that no one is selling yet.

So why not lets arrange a group buy before some vendor claims it? Now is the time on a brand new motor.

Is anyone planning a groups buy? i found an old group buy on a mxuss motor and it seemed to sale for very cheap.

Now the only place to get an affordable Mxus is alibaba.

 

[markz]

A group buy would benefit a lower price, but someone has to step up and do it.
For myself, I will buy when Chinese new years is over.

 

[Quokka]

I have been in contact with mxus yesterday through alibaba....mxusebikekit. most frustrating experience of my life. Their sale guy is completely useless. I have absolutely no confidence that you will get what you ask for. The guy had no idea about kv ratings and just responded to every question- it will do 100km/hr... if you are after a winding thats not 3t, i think there will be problems. They say production is 3 weeks away- only useful info from about 10 emails back and forth

 

[teslanv]

I have been in contact with mxus yesterday through alibaba....mxusebikekit. most frustrating experience of my life. Their sale guy is completely useless. I have absolutely no confidence that you will get what you ask for. The guy had no idea about kv ratings and just responded to every question- it will do 100km/hr... if you are after a winding thats not 3t, i think there will be problems. They say production is 3 weeks away- only useful info from about 10 emails back and forth

I covered my estimated Kv ratings for the various windings earlier in the thread. I'd bet they will be more accurate than anything MXUS can quote you.
My math is based on a linear relationship between winding turn count and Kv. Max Continuous phase currents are based on 6.00A per strand in parallel (Same current/strand as the 3K-Turbo Max Phase current's that Grin Provided with their Dyno Tests.)

I am wondering with the KV rating as high as it is if this motor would benefit from say a 25x4T winding? I am guessing that would bring the KV down to around the "10ish" range .

I don't see why not. A 25X4T winding would likely get the Kv down to around 10, if my math is good.

Here are my mathematical estimates of Winding to Kv for all windings of the 5K motor design:

33X3T = 13.47 Kv, Max continuous Phase current of 198A
25X4T = 10.07 Kv, Max continuous Phase current of 150A
20X5T = 8.05 Kv, Max continuous Phase current of 120A
16X6T = 6.71 Kv, Max continuous Phase current of 96A

 

[Rix]

I have been in contact with mxus yesterday through alibaba....mxusebikekit. most frustrating experience of my life. Their sale guy is completely useless. I have absolutely no confidence that you will get what you ask for. The guy had no idea about kv ratings and just responded to every question- it will do 100km/hr... if you are after a winding thats not 3t, i think there will be problems. They say production is 3 weeks away- only useful info from about 10 emails back and forth

I covered my estimated Kv ratings for the various windings earlier in the thread. I'd bet they will be more accurate than anything MXUS can quote you.
My math is based on a linear relationship between winding turn count and Kv. Max Continuous phase currents are based on 6.00A per strand in parallel (Same current/strand as the 3K-Turbo Max Phase current's that Grin Provided with their Dyno Tests.)

I am wondering with the KV rating as high as it is if this motor would benefit from say a 25x4T winding? I am guessing that would bring the KV down to around the "10ish" range .

I don't see why not. A 25X4T winding would likely get the Kv down to around 10, if my math is good.

Here are my mathematical estimates of Winding to Kv for all windings of the 5K motor design:

33X3T = 13.47 Kv, Max continuous Phase current of 198A
25X4T = 10.07 Kv, Max continuous Phase current of 150A
20X5T = 8.05 Kv, Max continuous Phase current of 120A
16X6T = 6.71 Kv, Max continuous Phase current of 96A

You did and concurred my SWAG guess at 10ish KV for a 25x4T motor, and my money is, you are on the money. What needs to happen next is get these motors and try them.

 

[Merlin]

I would not expect that much "more" quokka
Not to swap out your q3 for that.
At these power levels you ride iam sure that benefit is more "slightly" or more to measure from
Luke on his dyno.

If I) or offroader) compare mxus v3 (9kg) to cro motor v3(11kg)
It feels same except of a faster heated up motor.

The mxus v3 (9kg) vs qs v3(12,5kg) is beside the also 3 times faster heated mxus.. Noticeable for every rider. A real benefit with weight penalty...

What can we expect from the same weight class in real world tests?
I bet.... Nothing worth for switching a 500 dollar rear wheel.

I would put your finger on a 273.

 

[minde28383]

Merlin,
Do you say that torque of mxus v3 is the same as qs v3?
For eq.: batt 100a and 250a phase.

 

[litespeed]

No. MXUS V3 and old cromotor ( QS V2 )are similar but QS 205 V3 is in league of its own.

273 motor is just crazy powerful.

Tom

 

[markz]

273 motor is just crazy powerful.

I am getting a boner again.
What are the equivelants to the 273? Cromotor, Crystalyte 54xx?

 

[Ohbse]

273 motor is just crazy powerful.

I am getting a boner again.
What are the equivelants to the 273? Cromotor, Crystalyte 54xx?

Not even close, Cromotor is the same as a 205mm 'V2' QS, 54XX is at best on par with that. 273 is substantially more motor, almost double the weight of the original Cromotor... of course it's going to be more powerful. A 273 will still be out of saturation with 800a phase, it's simply too much motor for a <50kg bike (not like that's a bad thing!)

As of yesterday I'm running 180a battery into a QS 205 v3 3.5T (13.5kv) and it's ridiculous, Honestly don't see a further 50% increase being actually usable on an 'ebike'. The 273mm+ things are really for larger Motorcycle type rides where the performance is required to get the same power to weight or for prolonged higher speeds.

 

[litespeed]

Ohbse,

I'd love to see video of yours in action. I'm running the same motor in a 17" rim, 14KW MaxE and 20s15p Koinion cells. Battery is definitely my bottle neck right now although I can pull 196 amps or so is what the display shows. Problem is after 20 or 30 seconds I hit low volt.......total buzz kill.

Wondering between going back to 20s lipo (multistar ) or build another 20s12p or 22s12p 30Q battery?

Just had rotator cuff surgery (tore 3 heads and the 4th was "holding on by a thread" according to doc) so I have some time till I'll be riding again.

Would love to hear what your using.

Tom

 

[madin88]

Ohbse,

I'd love to see video of yours in action. I'm running the same motor in a 17" rim, 14KW MaxE and 20s15p Koinion cells. Battery is definitely my bottle neck right now although I can pull 196 amps or so is what the display shows. Problem is after 20 or 30 seconds I hit low volt.......total buzz kill.

Wondering between going back to 20s lipo (multistar ) or build another 20s12p or 22s12p 30Q battery?

Tom

what "konion cells" do you have?
13A per cell should be normally no problem for a konion VTC cell. Samsung 25R or 30Q wouldn't be better in terms of sag (or internal resistance).
But if you pulling more often and for longer periods of time so high current, unsing LiPos would be the better choice (aside from less sag also more lifetime i believe)

 

[litespeed]

I have the VTC 3 batteries. I can't stress enough that they work well for what they are but just don't last long enough. Maybe I would need to go 20s15p like I have presently which would give me an easy 100 continuous or 200 peak. Also 45 amp battery should last a bit as well. Even if I went 25R that would be a 37.5 amp pack.

Multistars would be cheaper and more powerful but heavier and have the gawd awful wiring harness with way to many connections.

Hate these crossroads but looks like lipos should be the direction I should go.

Tom

 

[Jestronix]

What's the kw max on the 5K, 14kw thru the mxus V2 opened my eyes to what's enough on a pushbike. Near 20kw ? I just don't know if I'd ever actually go WOT.

 

[Dumsterdave]

following

 

[markz]

I've been casually peaking in here. Will have to hit up MXUS website see if its available. Always didnt like the way MXUS does their Alibaba website, 38 pages to comb through.

 

[Dumsterdave]

I've been casually peaking in here. Will have to hit up MXUS website see if its available. Always didnt like the way MXUS does their Alibaba website, 38 pages to comb through.

It's not just the MXUS alibaba site. I find all of alibaba confusing as hell. I think all the sellers just put a bunch of random things there with wide price ranges and confusing specs.

 

[markz]

Maybe it is Asian culture perhaps.

 

[markz]

spoted on Alibaba:

same?

http://mxus.en.alibaba.com/product/...s_72v_5000w_for_electric_bike_rear_wheel.html

Doc

Wonder what the wait time is on it.

Q1. What about the lead time?
A: 7-10 days for sample order, 30-45 days for bulk order.



Q2. Do you have any MOQ limit for order?
A: Low MOQ, 1pc for sample checking is available



Q3. How do you ship the goods and how long does it take to arrive?
A:EXPRESS,Airline and sea shipping also optional.It usually takes 7-10 days by express or airline/ 20-35 days by sea.



Q4. How to proceed an order for E-bike kits?
A: Firstly let us know your requirements or application.
Secondly We quote according to your requirements or our suggestions.
Thirdly customer confirms the formal sample order and payment(By T/T,PayPal etc.)
Fourthly We arrange the production and strict test before shipment.





Q5.Do you accept OEM orders?

Yes, we are the factory can do any OEM


Q6.What kind of extra preferential you would like to offer?

Return the sample cost after bulk order placed.