MXUS and MAC wonders

Joined
Mar 29, 2016
Messages
383
Hi,
I am not asking about their performance/ratings. I already red that.
Maybe it's a question for Grin, but thought to ask it here as they are quite busy lately:
What I wonder, if those motors are so good in their specs (The MAC 12t in particular seems nothing short of breathtaking), why Grin doesn't stock and sell them?
I discovered them for the first time via their Trip-Simulator, and initially thought that the MAC 12t has some "errors" in it's super-specs.

Roy
 
miuan said:
Simply because Grin have their EZEE geared line as a direct competitor.

But they have two lines of geared motors (ezee and Bafang at the moment), as well as several lines of DD's: Crystalyte, 9C, TDCM...
It doesn't seem to be an exclusive market approach.
 
thunderstorm80 said:
they have two lines of geared motors (ezee and Bafang at the moment), as well as several lines of DD's: Crystalyte, 9C, TDCM...
It doesn't seem to be an exclusive market approach.

True, but the Bafang is not the same power league as MAC / eZee.
 
Mac is too expensive relative to the performance benefits they offer. They are also sold only by Cutler Mac and require their own controllers which are also expensive and compete too closely with the BBS motors in price. As a company I find them difficult to deal with.
Just saying.
It's been a while since I posted here
Gunther
 
I about to move away from mid drives to Mac simply because I can get a better price than eZee. My San Fran friend loves his. Easy fix, easy and cheap enough to stock basic replacement parts too. Grin can't sell them all and they've done special projects with eZee. Nice to see a company stay loyal to it's suppliers. They could make more and sell copy cat nine continent too, but they don't.
 
Also probably because EM3EV has that market cared for.

Grin seems to be more focused at developing and improving new ebike tools and accessories rather than reselling things that are merely popular in the market. There are plenty of other vendors to fill that niche.
 
gunthn said:
Mac is too expensive relative to the performance benefits they offer. They are also sold only by Cutler Mac and require their own controllers which are also expensive and compete too closely with the BBS motors in price. As a company I find them difficult to deal with.
Just saying.
It's been a while since I posted here
Gunther

Expensive?
http://em3ev.com/store/index.php?route=product/product&path=50_40&product_id=52
They cost about 40% less than the eZee, yet according to their specs the Mac's have better kV motor-constant combined with lower phase resistance.

Can someone explain how is this possible, or where is the catch? :D
 
where is the catch? :D
No catch. I do not mean to dis eZee in any way, since I have never owned one. Can say from personal experience though that the MAC is great motor and solid value. Out riding on a MAC-equipped bike today. Smooth, pretty quiet, pretty powerful, just works.
 
gunthn said:
Mac is too expensive relative to the performance benefits they offer. They are also sold only by Cutler Mac and require their own controllers which are also expensive and compete too closely with the BBS motors in price. As a company I find them difficult to deal with.
Just saying.
It's been a while since I posted here
Gunther

I just have to call BS on the whole "require their own controller" part, where did you even get this? I run a mac motor with an phaserunner, no issues at all...
 
Right.. so the eZee is eye wateringly expensive compared to the MAC, and i have yet to find someone who has bought one and taken it apart and identified where exactly the extra ~$200 asking cost is.. :lol:

So i ordered one from ebikes.ca a week ago and will be pulling it apart. I hope someone will pull apart a MAC with me and compare side to side. :)

From what i hear, it is power equivalent to the MAC these days, as it has a wider stator than before. Yet, it is about 1.5lbs lighter. The lower weight is appealing to me as i have a wagon these days and wanted to build a bike that is light enough to chuck in the wagon. Currently i have a 60-70lb DD hub and RC Lipo powered monster that is not fun to throw in the wagon at all, thus i never do any riding at exotic locales. I just commute locally, which is cool and all, but..

1.5lbs isn't a big weight difference, but i wanted the best power to weight ratio i could get. Getting a better ratio than an eZee would require going to mid drive or RC drive, and both of those options would cost significantly more / have more maintenance hassles and considerations, so by contrast, the eZee isn't all that expensive.

Think about it like this.. a bafang bbs02 adds about 8lbs to a bike and puts out 750w continuous or maybe even lower.. an ezee is rated for 1000 watts or 1200 watts, depending on what vendor you're talking to.. power to weight ratio wise, it does whoop a BBS02 and a lower end GNG for sure..


One note.. the MAC motor in the ebikes.ca simulator is a very old version with 0.5mm lams, and the performance you see isn't representative of MAC motors today. The newer eZee has 0.35mm lams and probably performs better and has higher efficiency on the simulator.. one could imagine that the MAC performs the same as that, if not better.

0.27mm lam MAC motors are also trickling out in to the public right now. In a 26" wheel, my educated guess based on recent dyno sheets i've received from cutler mac is that that these are 1-3% better in efficiency and continuous power output. In a 20" wheel, i would imagine that the power increase would be from 3-7%.

But i think that the small weight penalty of the MAC still puts the eZee ahead as the #1 power to weight ratio geared hub.
 
neptronix said:
But i think that the small weight penalty of the MAC still puts the eZee ahead as the #1 power to weight ratio geared hub.

I disagree. According to the newer ebikes.ca Trip Simulator, both the Mac 12T and the ezee 250rpm have the same motor constant.
The Mac, however, has less than a quarter of the phase resistance! (again - same motor constant for both).
That means that the Mac has TWICE the power/weight output, since it's only about 30% heavier than the eZee. (The square root difference of the Phase-resistances)
It does have twice of the hysteresis losses, but when comparing power outputs in the order of 1000W, it becomes negligible.

Am I right about this?
I don't know how's the Mac's reliability and internal construction. Maybe that's where the eZee shines, and the reason why ebikes.ca are sticking with them, as their moto is to only stock long term reliable products and maybe that's the "catch".
 
Unless you can show me that the MAC is actually a 2000w continuous motor that has been incorrectly rated by MAC themselves, i'd have to call you wrong. In the ebikes.ca motor simulator, the 0.5mm lamination MAC is modeled which has a much lower continuous power output than the current eZee that is modeled. The trip simulator is not the right tool for comparing motors.
http://www.ebikes.ca/tools/simulator.html

Phase resistance does not tell you everything about a motor, and you very well may have incorrect figures or ones that were measured differently. Design of a motor can tell you a lot more. At most, the MAC stator is going to be 10% wider than the ezee. With equal pole count and stator height, you'd not be getting twice the continuous power out of a stator that is 10% wider.

Also, 10lbs VS 8.5lbs is not a 30% weight difference, it is 15%.

I ran a 2011 era 0.5mm lam MAC motor for 3 years. I was almost 100lbs heavier than now and rode it along a lot of broken pavement and even put 4kW into it once and overheated it in 5 mins and then replaced the gears that melted.. then i proceeded to ride it up 7% grades too at 1600W carrying my fat ass up, demagnetized it significantly in the process, and kept riding it.. it is one of the most reliable motors i'd ever owned and i would buy another.. you are not cheaping out of you buy one.

But if you want the best geared motor, i think the eZee is going to be it.. we'll see if the juice is worth the squeeze in a week or two.. :)
 
neptronix said:
Unless you can show me that the MAC is actually a 2000w continuous motor that has been incorrectly rated by MAC themselves, i'd have to call you wrong. In the ebikes.ca motor simulator, the 0.5mm lamination MAC is modeled which has a much lower continuous power output than the current eZee that is modeled. The trip simulator is not the right tool for comparing motors.
http://www.ebikes.ca/tools/simulator.html

I heard from Justin itself that their motor-simulator is getting out-dated since it carries 2008 data for their ezee motor. Dunno if it's also for the MAC. Their Trip-Simulator is a much more advanced and more updated version and also account for the technology advances (smaller laminations for example). You can test it and see that you get a complete different performance from the ezee if you run both simulators side by side.
Why you say the Trip-Simulator is not the right tool? I know it doesn't have the comparison feature, but I prefer to work with an updated model rather than 2008 one.

neptronix said:
Phase resistance does not tell you everything about a motor, and you very well may have incorrect figures or ones that were measured differently. Design of a motor can tell you a lot more. At most, the MAC stator is going to be 10% wider than the ezee. With equal pole count and stator height, you'd not be getting twice the continuous power out of a stator that is 10% wider.

Isn't the thicker stator, higher pole count, etc - already modelled into the motor constant? After all, they are part of what's defining it, isn't it?
And assuming same motor constant but quarter the resistance, then yes, you can input twice the current to have twice the torque but same copper losses. I am not right about this?

neptronix said:
Also, 10lbs VS 8.5lbs is not a 30% weight difference, it is 15%.
Even better for the Mac...

neptronix said:
But if you want the best geared motor, i think the eZee is going to be it.. we'll see if the juice is worth the squeeze in a week or two.. :)
That is my question - Why you still recommends the eZee, after all what you wrote about the Mac?
 
Not sure where you got that.. on the ebike simulator, they list the pre 2013 motors and the current motors distinctly.. and 2013 is right around the time ezee switched to the thinner lams.. as well, the ezee motors simulated match the efficiency of a thin lam mac.. thus, we can safely assume the ones currently modeled are the current motors, yes?

I don't know why the trip simulator is better. It can tell you more over a long period of time, but less information for a fixed period of time. I want to know what the fixed point is before i look at the long data.

Turn counts, pole counts, stator dimensions, and reduction ratios ( since we're talking about geared motors ) do determine the motor constant, AKA KV, but the KV doesn't say anything about motor performance. What happens under load does.... and the more copper and steel and magnets, the better, to put it simply.

Phase resistance is not the end all value to look at. It may be a quarter lower due to something silly like measurement differences or one motor having thinner phase wires and a wimpy connector at the end. It can simply be that. Phase resistance is simply a value of how much resistance there is along the total length of copper. It is only a good figure for looking at two motors of the same stator dimensions. Even then, it won't give you the full picture.
I'll give you an example. The leafmotor versus a 35mm 9C clone with 0.5mm lams. The two motors could have identical phase resistance, being wound exactly the same. But the leafmotor produces 25% more continuous power.. just because we were thinking about phase currents and not factoring in the huge difference in eddy losses..

I don't recommend the eZee. I just came here to tell you that i bought one to find out if it puts out equivalent power despite being 15% lighter. I may very well also have a MAC on order later on with a similar wind and identical wheel size for a friend. You wanted to know why the eZee was so expensive and i am curious too so i'm finding out. :mrgreen:
 
I'm getting a new MAC 8T from SamD with the .27mm lams very soon. It's going to replace an older 8T on my wife's bike. She's getting a new motor for the thinner lams, better wire exit, and cassette gearing. I wasn't planning on taking it apart, but for the group, I'd be willing to crack it open and take a couple glamour shots.

Older 8T is getting moved over to another wheel for backup duty.
 
Hope it's okay to ask in this thread as I'm also wondering about the MAC motors. I'm I correct in thinking that all MAC geared motors have the same gear reduction? And that only the winding of the motors differ from 6T up to 12T?
 
SlowCo said:
Hope it's okay to ask in this thread as I'm also wondering about the MAC motors. I'm I correct in thinking that all MAC geared motors have the same gear reduction? And that only the winding of the motors differ from 6T up to 12T?

Yes. 5:1 reduction ratio using clutched planetary gearset.
 
cal3thousand said:
I'm getting a new MAC 8T from SamD with the .27mm lams very soon. It's going to replace an older 8T on my wife's bike. She's getting a new motor for the thinner lams, better wire exit, and cassette gearing. I wasn't planning on taking it apart, but for the group, I'd be willing to crack it open and take a couple glamour shots.

Older 8T is getting moved over to another wheel for backup duty.

Awesome. Pop me a PM when you get it in, or i'll send you one. We can start a joint thread and figure out what's what with these motors.
 
Will do. Timeline got pushed back a bit, so about 3-4 weeks and I should have it in my hands and splayed out.
 
neptronix said:
Not sure where you got that.. on the ebike simulator, they list the pre 2013 motors and the current motors distinctly.. and 2013 is right around the time ezee switched to the thinner lams.. as well, the ezee motors simulated match the efficiency of a thin lam mac.. thus, we can safely assume the ones currently modeled are the current motors, yes?
Justin told me that the ezee motor on the older Motor-Simulator is based on 2008 data. As I said, simulate both for a certain work point along with the Trip-Simulator, and you will see a significant performance difference.

neptronix said:
I don't know why the trip simulator is better. It can tell you more over a long period of time, but less information for a fixed period of time. I want to know what the fixed point is before i look at the long data.
The Trip-Simulator doesn't only carry updated motor data (along with the option to add Statorade), it also gives you the most accurate thermal data regarding temperature rise vs time (and you can tweak the motor's heat-transfer parameters as well), while the motor's simulator is a simple first-order model that doesn't account for wind cooling. The older motor simulator is also quite inaccurate for regen conditions.
You can also see the motor's kV, resistance, magnetic losses, and you can tweak any of them to learn better.
It's a way more accurate tool to know what performance you will get, but of course there is no two systems comparison, and you don't see the motor spec vs rpm graph.

neptronix said:
Turn counts, pole counts, stator dimensions, and reduction ratios ( since we're talking about geared motors ) do determine the motor constant, AKA KV, but the KV doesn't say anything about motor performance. What happens under load does.... and the more copper and steel and magnets, the better, to put it simply

Phase resistance is not the end all value to look at. It may be a quarter lower due to something silly like measurement differences or one motor having thinner phase wires and a wimpy connector at the end. It can simply be that. Phase resistance is simply a value of how much resistance there is along the total length of copper. It is only a good figure for looking at two motors of the same stator dimensions. Even then, it won't give you the full picture.
I'll give you an example. The leafmotor versus a 35mm 9C clone with 0.5mm lams. The two motors could have identical phase resistance, being wound exactly the same. But the leafmotor produces 25% more continuous power.. just because we were thinking about phase currents and not factoring in the huge difference in eddy losses..
I don't talk about faulty connections or engineering design errors like too-thin phase wire leads into the motor's body. I talk only about it's optimal performance, assuming the proper phase-wires, correct air-gap spacing, etc...
The kV go along with the phase-resistance, hysteresis and eddy losses, which are the four parameters that define a motor in the trip-simulator.
Physically it's the kV divided by the square root of the Phase-resistance figure, that define the machine's power capability, so all H35XX motors have the exact performance but with either low kV and high resistance and vice versa. That figure stays constant within the same family of motors.
But, if I do this calculation for the H35 series with their wider 35mm stator and magnets, vs the narrower 27mm of the 9C+ 27XX, I will find both families have around the same net result of kV/sqrt(phase-resistance).
Since the Trip-Simulator calculates the motor performance only according to the four values, how come the H35 is more powerful?
It's actually around 35/27 more powerful, but there is no field to fill up for that. Only kV, resistance, hysteresis, and eddy.
So how does it know? Where do the 35mm vs the 27mm takes place in the calculations?

neptronix said:
I don't recommend the eZee. I just came here to tell you that i bought one to find out if it puts out equivalent power despite being 15% lighter. I may very well also have a MAC on order later on with a similar wind and identical wheel size for a friend. You wanted to know why the eZee was so expensive and i am curious too so i'm finding out. :mrgreen:
I assume because the eZee is a much more reliable motor in mechanical terms.
Justin told me not long ago about a company in New-Zealand that manufactures electric off-road motorcycles which uses two ezee motors.
I would have assumed hub motors would break in short order on high-speed off-road trails (due to their high unsprung weight), but apparently the ezee doesn't.
I am now building a hard-tail MTB that has the ezee motor on it's rear wheel, and I plan to take it high-steep off road single tracks (but not aggressive ones). With less than 4Kg, and having it's clutch welded&locked, it should be the perfect off-road machine - mostly because of the regen capability, which I have already tested: You can glide -12% grade at 10Km/h and still recharge your battery quite well. You enter plug-braking only at standstill speeds - like 1-2km/h.
 
I might have been the one to make the MAC motor popular on this forum, have built several bikes with them, found their performance limits, and have tons of information on the other related large geared motors ( BMC, eZee ) i could rattle off the top of my head based on relationships with every large vendor who has ever sold one over the course of 7 years, but.. it's your thread and you can believe whatever you want to believe. :mrgreen:

But the truth is.. eddy losses, hysteresis, kv, and phase resistance don't tell you everything about a motor, but they are the only parameters the motor simulator and trip simulator will accept and can model based on. But with wrong figures ( like 2 motors of the same size and one has double the phase resistance of the other ), you will get wrong data - like the assumption that a modern MAC can output double the power of a modern eZee. The eZee used to have a much smaller stator.. and it most likely had thinner phase wires.. so are you using the old phase resistance value.. or the new?

An ezee that performs at 84% peak efficiency in the simulator is absolutely not an old 2008 version with 0.5mm laminations. Neither the MAC, BMC, or eZee of any stator size with 0.5mm laminations can achieve that peak efficiency at all.. the 0.5mm lamination versions of all 3 motors barely touch 80% efficiency. 0.35mm always hits 82-84% peak. That is how you will know which model is which.

...but both generations of eZee are in the motor simulator and are clearly labeled. Thus, if you are looking at a new eZee, use the motor simulator if the trip simulator only contains data for the old motor. The BMC V1 and V2 in the motor simulator are both 0.5mm lamination versions. The MAC 10T and 12T that are listed are either the 0.35mm versions or 0.27mm versions, i am not sure which. It appears the MAC can peak at 85% efficiency, which is super impressive yet contrary to the dyno sheets i have seen from MAC's sales department; although it looks like MAC's dyno testing regimen was not done correctly.
 
If MAC is still winding their different versions with different amounts of copper, then I have 0 respect for them. ie same diameter magnetic wire just with a different number of turns being the difference between versions of the same motor. That was the main reason their speedier wind motors always had more heat problems.

The comparison is simple enough...a 12t motor should have 4 times higher phase-to-phase resistance of a 6t motor. ie. the windings should be twice as long and half as thick for the same total amount of copper.
 
gunthn said:
Mac is too expensive relative to the performance benefits they offer. They are also sold only by Cutler Mac and require their own controllers which are also expensive and compete too closely with the BBS motors in price. As a company I find them difficult to deal with.
Just saying.
It's been a while since I posted here
Gunther

What? Too expensive? The Mac w/controller and hardware from EM3EV is 500ish. The Grin version (Upgraded to Grin spec) is 800ish. The performance in the same Watt Rating is pretty similar... I've read as much as I can find on them. Can your post links I should be aware of?

The Grin Bafang Geared is a 36/43 volt motor. Not in the same league as the Ezee. I just bought the new Mac front w/side Exit and it's a pretty nice motor... improved from their old version. Is it "better" or as good as the Ezee? I don't know. Part of the Grin pricing model is their upgrades, their controller options, standardization on connectors, and the included Schwalbe Tire.

One problem I've encountered with the New Mac is the motor may come in contact with forks (like mine) where the drop outs are centered. The exit cable is a little "tight" (slight washer interference) and is aligned with the axle cut out. I also had to file down the axle flat on one side to fit a 2nd torque arm... so maybe the Ezee is manufactured to a higher tolerance.

It's my understanding there will be a black (not silver) version of the Ezee... but I have not seen it yet. Perhaps this is only cosmetic, or perhaps it's cosmetics and improved. I wish the Ezee had a side exit cable because it makes installation easier (IN the event you want to swap out or rearrange washers, slide on a torque arm, or service the clutch if it fails).

EM3EV supplies longer stock wiring which fits my current needs, whereas the Grin requires me to have an extension.

Grin has to make a buck and can't carry everything. Perhaps the reliability the Ezee offers is much better? Perhaps Ezee as a company offers better terms, perhaps stock "float"... who knows.

The difference is about $300 at retail.

So can anyone here verify if there truly is a quality difference, better clutches, better wiring, better halls?

It's my understanding that Grin offers a 2 year warranty. EM3EV warranty?

It is what it is. I may end up purchasing the Ezee (But I really want the black, and I really don't want the cable exiting out the axle)... because it may now be my only option.

The G01 Bafang is a consideration, but my batteries are all 14S 52 volt and I'm not sure they would play well with the small motor. I've also read that they can heat up pretty easy above 500 Watts... and the Mac has not heated up on me up to 1000 watts and I have confidence the Ezee won't either.

There are not perfect motors, and not perfect vendors but both Justin and Paul are just about the best you'll find. And both seem to actually give a damn about customers.
 
Jcr
Is that true!? If so you may have just cleared up a long standing question of mine. A long time ago when I still believed in torque and speed winds (well ok it was only a few yrs ago and I was set straight by the hugely educational thread here on ES), my mate had two macs one fast one slower. His fast wind would always hit thermal roll back on his home hill so he bought a slower one (at my recommendation :pancake: ) and got up ok..hot but ok. A few weeks later I learnt more about motors but I've never known why he had his results... Till possibly now.
 
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