Has anyone tried both and compared a Cromotor to a MXUS?

[Offroader]

I am yet to read anyone who has tried both motors, preferably with the same bike.

Cromotor or QS205 motors weigh in at 12.00 to 12.9 KG (with extra copper fill), MXUS weigh in at 9.14KG. I've personally only used Cromotors.

Since I can watercool + Aircool a MXUS, heat shouldn't be an issue for buying a much bigger Cromotor/QS205.

So I am more concerned if there will be a huge difference in power, and especially torque for acceleration and climbing. I need to determine if the extra 3 to 4KG of weight is worth it for a cromotor.

 

[Offroader]

I'm not surprised that no one has responded because I am yet to find anyone on here using and comparing both motors.

These are the issues I am seeing here. The MXUS 3000 is around 9KG, the Cromotor is around 12-13KG.
The QS205 motor that people are ordering now is close to 13KG!

However the stator width is 45mm on the MXUS and 48 on the Cromotor. My thinking is that it doesn't make sense to use a Cromotor or a QS205 for 3-4KG of extra weight, especially if you will watercool or aircool the motor.

If someone has used both motors, preferably a 4T MXUS 3000 and a Cromotor/QS205, and can say that the power difference isn't all that much then in my opinion it is worth buying a MXUS3000.

I think the Cromotor may have a lot of unnecessary weight added to it. There was a post where someone filed down the magnet ring to save 1650grams. Lets also not forget about how much people drill the side covers out without issues.
https://endless-sphere.com/forums/viewtopic.php?f=2&t=55211

My thinking is that the hubmotors (especially the cromotor and QS205) are built way too heavy and strong for our ebikes, kind of like using motorcycle rims and tires on our ebikes. All of this stuff adds a lot of weight because it was intended to be used on much heavier bikes.

The MXUS3000 may be built less strong but still way adequate for most of us and well worth the weight savings in the rear where it messes with the suspension.

 

[macribs]

Remember that with the weight comes more material. Which leads to more material to suck up the heat created by the motor. I am not so sure the weight difference between those motors are big enough to solely let the weight difference influence your choice. What I mean is that if you ride demands so much from your bike that 4-5 kilos will make or brake a motor deal then maybe what you want is not a DD hub after all? I mean even with the mxus 3K, we are talking 20-25+lbs for motor/wheel/tire/tubing. Then there is rotor/caliper. All this weight is unsprung weight where it hurts the most. A mid drive would remove the weight away from the rear wheel and would make for a very capable offroad bike.

That being said, I know madin88 has tested both. In fact IIRC he swapped his cromotor for a mxus 3K. And the latest is that Madin88 has milled grooves/fins on the outside shell of the motor between the flanges for increased area and better cooling. About 1 kilo of material was removed, making the mxus 3K around 7 kilo in total. Now that should improve cooling as well as have significant improvements on the handling. The flanges themselves could also loose some material, like those crystalite motors.
Shoot him a PM.

[youtube]9FZrJBWQ7-g[/youtube]

 

[cwah]

would be interested too as from 8kg to 12kg it's 50% more eight added and only 5mm more magnet width!

 

[Offroader]

My current raptor weighs a whopping 135LBS.

With my current build, a Q176R from Qulbix, I'm looking to do a light weight build and try to knock my weight down to around 100 pounds, with a 3KW Hour battery.

The Cromotor does suck in a lot of heat but I have two options with a MXUS motor to actively cool it. The first is using my EDF fan cooling which works great on my cromotor and I can adapt it into the MXUS. Or I can water cool the MXUS 3000 as madin88 makes an axle to allow for cooling hoses.

I already can knock around 10lbs from the battery, another 10-15 lbs alone from the reduced frame weight of the Q176R, so a Mxus may give me another 10lbs to meet that goal of 100lbs.

Thanks macribs, I'm giong to shoot IIRC a private message to see what he thinks.

 

[Offroader]

would be interested too as from 8kg to 12kg it's 50% more eight added and only 5mm more magnet width!

Actually not even, someone measured the lamination to 48.XX, and I believe that is correct because when I had to reglue my magnets the magnets were exactly 50mm, but the stator was smaller and I didn't worry as much of lining the magnets up exactly.

Not sure if the magnets size or the lamination size is more important. But we are talking very little size in width here vs a cromotor, but much heavier.

A reason I believe is the Cromotor is designed for a heavy scooter while a Mxus is designed for Ebikes in mind. I'm basing it on this review here.
https://www.electricbike.com/mxus-3000w-hubmotor/


MXUS is located in Chang Zhou (just west of Shanghai), and they have been a long-time manufacturer of hubmotors for several branded retail companies that make electric bikes. Apparently, a few years ago they decided to also begin selling their products directly to the public under their own name.

 

[macribs]

More info added to my previous post:

https://endless-sphere.com/forums/viewtopic.php?f=2&t=74972&p=1131766#p1131766

 

[Offroader]

I think the MXUS 3000 has been updated to be heavier. The new 4T motors weigh 9.14kg from the factory. Not sure where the old spec of 8.3kg came from.

My cromotor v3 weighs ~12.00kg

The QS 205 with I believe with extra copper fill (not sure if all have this option now) weighs 12.9 kg.

So the MXUS vs the Cromotor v3 is only around 3kg difference.

 

[ecycler]

evolutiongts went from a cromotor to a MXUS3000 as well. See his build thread:

https://endless-sphere.com/forums/viewtopic.php?f=6&t=62159

I very much enjoy the MXUS3000 4T on a 17inch moto rim with 2.75 SR241. It is the perfect amount of power and specific heat capacity/dissipation for my uses at the power level I am currently running. I can run 1.5kwh through it @3000w over hilly terrain and it is right at 90c when I get back home. The extra mass of the cromotor does not benefit my current needs unless I really turn up the power which would require riding too fast or hard for the given environment.

 

[Offroader]

Thanks, I'm going to check out his build thread.