Favourite high power hub motor?

[Bullfrog]

Everybody has different criteria and each motor has advantages and disadvantages. IMO a MAC is one extreme and a QS273 is on the opposite end of the spectrum.

I personally like the 45mm wide stator motors that Grin Tech and EM3ev offer...they are about middle of the road in most respects. If I was going to run high amperage for very long, I'd probably go with a QS205 50H motor .

But like I tried to imply above, getting from 0-20 mph quickly is more important and more fun for me than higher speeds so the MAC works for me . Don't mean to imply it is a good choice for everyone by any means :wink: .

 

[Jonno]

Well said Bullfrog

 

[MadRhino]

Weather was nice today, streets clean, not much trafic. I came in town to shop things we can’t find in the countryside. I did ride the 3’’ slicks on the QS205h50. I love this bike.

 

[markz]

Weather was nice today, streets clean, not much trafic. I came in town to shop things we can’t find in the countryside. I did ride the 3’’ slicks on the QS205h50. I love this bike.

Did you bring along the hand sanitizer, gloves, full face shield, N95 masks and 2 meter stick?

 

[Bullfrog]

I tried a Vee Tire Co. 26x4.5" slick recently...did not like it at all, rubber was 72-73 Durometer and it was advertised as 57.

I have not had good luck with any "Vee" tires...YMMV .

 

[MadRhino]

Weather was nice today, streets clean, not much trafic. I came in town to shop things we can’t find in the countryside. I did ride the 3’’ slicks on the QS205h50. I love this bike.

Did you bring along the hand sanitizer, gloves, full face shield, N95 masks and 2 meter stick?

I ride too fast to be caught by a virus, and to let anyone come 2M on my tail.

And, I smoke 2 packs a day. Aero viruses die in the tar like flies on a flypaper trap.

 

[markz]

Riding your ebike up and down the aisles of the small Quebecois town shops, seems like the sane thing to do. I agree, the Kung Flu has no chance in catching up with you, especially with the QS205 50H motor.

Weather was nice today, streets clean, not much trafic. I came in town to shop things we can’t find in the countryside. I did ride the 3’’ slicks on the QS205h50. I love this bike.

Did you bring along the hand sanitizer, gloves, full face shield, N95 masks and 2 meter stick?

I ride too fast to be caught by a virus, and to let anyone come 2M on my tail.

And, I smoke 2 packs a day. Aero viruses die in the tar like flies on a flypaper trap.

 

[Bullfrog]

I am going to have to back off of my speed recommendation in the post below ...after more experience with my new 8T MAC, I'd have to say if you want to go over 28-30 mph then a MAC is a bad idea. With my total weight of 274 lbs and running a 52v battery, and a 26" Hookworm tire...my 8T MAC will only do an honest 28 mph on flat ground. IMO the Grin Tech Motor Simulator under estimated my frontal area and/or my rolling resistance :lol: . So now my official stance is under 28 mph, get a MAC...want to go 28 mph or faster, then you'll be a lot better off with a Direct Drive Hub Motor.

As you can see, the MAC/GMAC definitely have some limitations BUT if you want to get from zero to 20 mph faster than anyone with the same amperage...a MAC is still the ticket .

YMMV...above is just my experience :wink: .

Just to add a little more info...

If you run a heavy high power motor you will also need better brakes and more weight in the front to get the bike to handle decent. If you don't have a reasonable weight distribution, when you go to turn the front wheel will slide and you will end up having the earth to come up and meet you very quickly :lol: . I speak from experience :wink: .

So everything needs to be considered and balanced...a huge, heavy, high powered motor like a QS273 is great but remember you have to feed the motor so a larger battery, a larger controller, larger brakes, larger tires, stronger wheels, etc. may be required. I am not saying you can't or shouldn't do it...just that it isn't as simple as buying a bigger motor.

You need to start with a good frame and one option I discovered is the "Nyx" frame: http://www.nyxbikes.com/nyx-frames. Turns out, doctorbass who commented above was involved in the development of the frame so there is somebody with some actual high powered ebike experience behind it . There are a lot of other good options out there as well.

I'd also recommend paying fairly close attention to the comments by MadRhino...he has built several high powered bikes and is another one with experience.

Both doctorbass and MadRhino as well as a bunch of others have been very helpful to me. BUT I came to the conclusion that "speed" was not my primary objective...especially since dv/dt can get pretty traumatic the faster you go. For those not aware, dv/dt is the change in velocity vs the change in time and it basically means the faster you go the worse you are going to get hurt when you crash AND everybody crashes at some point.

My preference is to build a bike that has high acceleration from 0 to about 28 or 29 MPH. Acceleration is what your body feels and gives you an adrenaline rush...you can't tell the difference between 10 mph and 800 mph, they both feel the same assuming you are in an enclosed space.

My approach is to use the motor that has the highest acceleration per amp. It is a MAC geared hub motor. If you run every motor in the menu on the Grin Tech Motor Simulator, the MAC has the highest acceleration per amp except the 750W Bafang geared hub motor but the Bafang hub motor actually has little bitty phase wires so you can't feed it much amperage in reality...therefore the MAC is the king as far as acceleration per amp and the MAC only weighs 4.3 Kg.

The MAC does have limitations! If you want to go over about 30 mph the MAC is a bad idea...because it is a geared hub motor it does not reject excess heat to the atmosphere very well so if you want to push more than about 20A continuously (which equates to roughly 30 mph on level ground) through it then you need to find a different type of motor like a direct drive hub motor i.e. the QS 205/273, a Cromotor or etc. You can run much higher amperage through the MAC for short periods of time...see below .

If you want to feel a lot of acceleration (from 0-28/29 mph) and have a fairly light bike (my steel frame hardtail with a MAC and a 14s6p battery weighs 62 lbs) an 8T or 10T MAC may be the best motor for you .

Regardless of what type of motor you think you want, I'd highly recommend you run it through the Grin Tech Motor Simulator and see what the temperature does and compare it to other motors for acceleration and speed.

I have been running my MAC with a 52v battery and the 12 FET controller set to 40A battery and 112A phase current for several years and have never had a problem with the gears or the clutch. I ran both a 10T MAC and a Cromotor through the Motor Simulator and the MAC peak acceleration is 8.02 mph/s and the Cromotor is 6.98 mph/s...once you exceed about 20 mph, the Cromotor has higher acceleration.

The MAC is just another option...just be sure your circumstances do not exceed the MAC's capabilities. I have mine set to start reducing the power if the core reaches 130C and to shut down if the temps get to 140C. I came up with those numbers after Justin told me he ran a MAC at 145C on the dyno without any damage.

Remember...if you want to go faster than about 30 mph then go with a direct drive hub motor and if you want to ride off road then I'd recommend a mid drive like a BBSHD but for "fun per dollar" or fun per pound", it is tough to beat a MAC .

 

[DogDipstick]

Yea tried of the wieght I heat my bmc600 fs like my edge 1,500 but have more time to heat my muxus 3,000 v3 4t But this is my wieght limit A 205 to heavy.

I have always wanted to try a BMC V4 as a mid drive.

 

[Bullfrog]

If I was going to go through the effort to build a mid drive my first choice would be a BBSHD because it is a lot easier but I have difficulty seeing any advantage to a geared hub mid drive since you can change the gearing I'd go with a direct drive motor.

For me, the big advantage of a geared hub motor is the torque output because it is "geared". With a mid drive you CAN change the gearing so the geared hub motor sort of loses any appeal IMO .

 

[DogDipstick]

If I was going to go through the effort ... my first choice ...a lot easier ...difficulty ... any advantage ...geared hub mid drive...the gearing ...direct drive motor.

...me,...g advantage ...red hub motor... torque ... it is "geared". With..you CAN ...gearing s... geared hub motor sort of ... appeal ... .

BBSOHD has an intermediate shaft, ie is not direct drive, and has a set gear ration tween the intermediate and the output..

....so your argument is invalid.


Most mid drives I have seen are reduced and not direct drive.. but I think what you were getting at is that HD is easier top install.

.. and that would mean mine is invalid. Lol.

I just have been told great things about the BMC hubs ( both BMC /MAC hubs.) Dont know alot about them.





Hey someone thought it was a good idea... until the Cyclones and the GNG kits, undercut the price of such a setup and decided to leave Nomad Bikes in the dust.. Lol.... they were some well built drives.. using a BMC V2.... geared drive on the crank. Lol.

I guess you never heard of Ecospeed? Some communities ( recumbent) loved them. More power than a HD, US designed, and a solid piece of kit, once you consider th White industries and BMC quality they used.

Yeah. Im not pullig ideas out thin air here. Lol. It is a good ( excellent ) idea.. esp if the mid drive is one of those ballsy 3Kw BMC geared drives. IDk though, not speaking from exp.

https://www.google.com/search?q=eco...VmU98KHbADBPMQ_AUoAnoECAwQBA&biw=1216&bih=950

Thats a BMCV2 ^^^^^ in there supposedly.

 

[markz]

The highest geared motor would be the MAC, but whats the weight and cargo limit of a motor like that, would 375lbs eat the gears up for breakfast?

 

[Balmorhea]

The highest geared motor would be the MAC, but whats the weight and cargo limit of a motor like that, would 375lbs eat the gears up for breakfast?

If you match wheel diameter, winding, and voltage to the load you have to drag around, and you don't stuff too much power into it, then no problem. However, running hub motors with too much power, and too high kV for the speeds they can actually reach regularly, seems to be the (dumb) formula around these parts.

If the power the motor makes at 80% of its unloaded RPM isn't enough to propel you on flat ground at 80% of its unloaded RPM, I think you've made a mistake.

 

[John in CR]

The highest geared motor would be the MAC.

Not true, not even close. I've seen an electric motorcycle with a geared hubbie. I haven't been able to track down the manufacturer of the motor, but once I do I'll definitely share it on the forum.

 

[DogDipstick]

However, running hub motors with too much power, and too high kV for the speeds they can actually reach regularly, seems to be the (dumb) formula around these parts.

If the power the motor makes at 80% of its unloaded RPM isn't enough to propel you on flat ground at 80% of its unloaded RPM, I think you've made a mistake.

Im in this boat, and I want either a 205 4T or a 5T. It is a hard decision for me, Balmorhea.

I am here for the power. Goal is 50mph +. Any 300A+controller money can buy, any 300A+ battery money can buy is available to me. Total all up weight in the 240lb range.

I dont ( cannot ) decide on 5T and 120+v (30s) or 4T with 100v ( 24s). It is a very hard decision. lol.

The 5T is a 9Kv and the 4T is a 12Kv..... peak RPM range is 600-800 (goal) rpm on a 24" tire. Choice is 9Kv or 12Kv.

 

[Bullfrog]

Why not run them both through the Grin Tech Motor Simulator and see which one comes closer to giving you the performance you want.

If you don't have the exact parameters needed to build the motor in the simulator, use the Cromotor and change the Kv...it will get you a good approximation IMO.

As far as the MAC gears handling 400+ lbs...not a problem IMO. The clutch would be fine too. Overheating will be your potential problem. If you use a 20"/24"" wheel, you may be OK...use the Motor Simulator to see about the temps and plug in about 1.5% incline even if you ride on fairly flat ground.

 

[DogDipstick]

Why not run them both through the Grin Tech Motor Simulator and see which one comes closer to giving you the performance you want.



As far as the MAC gears handling 400+ lbs...not a problem IMO. The clutch would be find too. Overheating will be your potential problem.

Oh yeah I know how to use that GrinmotorSim thing. I just dont know if 240ftlbs(5T) or 210 ftlbs(4T) is enough for the needs given the peaks I can feed it. Choice denotes either, and the top speed within 10mph at 60 or 70mph. Based on that choice and the ranges I wish to use, and based on the controllers I am looking at, and the range of speeds I like to sit in.

The sim tells you easily if you are sitting in the
"controller killing zone" that likes to cook controllers in the long run... I do want durability and alot of reliability.. but... we talking high power here and there may be compromises to make.

What happens when you run a MAC at high speed low load? Do they heat up and soften the gears? Is it the high speed high tq they cannot take? Is it the amps that make the heat ( on low rpm on throttle tq creation) or the high RPM that makes the heat in those things? You can get alot of speed with med power, 30-40A.

 

[Bullfrog]

What kills a MAC is overheating the motor windings...IMO the stator would melt before the gears would give up...assuming the gears had some lubrication. I have run mine for several hours at wide open throttle and no problems with the gears...I lube them with Mobil 1 SHC 100. IMO a MAC will overheat if you try to push it above about 28-30 mph for relatively long periods of time i.e. steady state.

Regarding your choices...it sounds like you are going to be pushing the limits of all the components so it is a pretty tough call. Even if you have a high Kv and high voltage, you still need enough torque to push you and the bike at whatever speed you can "theoretically" achieve.

"MadRhino" has some experience in the realm you are exploring. He has been very helpful to me...I'd see what he has to say.

 

[AHicks]

Just my take here, but I think a call needs to be made on what kind of speeds we're talking about, and what percentage of time they will be ridden. The MAC (or any geared hub) are really not going to compete well, as compared to a direct drive, when talking speeds over about 25. Occasional speeds over that fine for short bursts, but a geared hub can't get rid of the heat like a direct drive can. So there's that factor.

Then too, a direct drive is pretty gutless at low speeds (lets say under 15mph), where a geared hub is not only much peppier, it's also much more efficient.

Point being, you need to come up with a set of 'druthers regarding your thoughts regarding how the bike will be used. Will it be peppy low speeds with some hills, or much faster speeds on fairly level ground? Unfortunately, there isn't a good hub solution that will do both. Not that I'm familiar with anyway.

 

[Tolkano]

Probably a mxus 3k lightened to about 8kg on a lathe would be my go to

Id lace it to 22" rims and run 22x2.5 tires, I can't stand the weight of heavy hub wheels

 

[Bullfrog]

Just my take here, but I think a call needs to be made on what kind of speeds we're talking about, and what percentage of time they will be ridden. The MAC (or any geared hub) are really not going to compete well, as compared to a direct drive, when talking speeds over about 25. Occasional speeds over that fine for short bursts, but a geared hub can't get rid of the heat like a direct drive can. So there's that factor.

Then too, a direct drive is pretty gutless at low speeds (lets say under 15mph), where a geared hub is not only much peppier, it's also much more efficient.

Point being, you need to come up with a set of 'druthers regarding your thoughts regarding how the bike will be used. Will it be peppy low speeds with some hills, or much faster speeds on fairly level ground? Unfortunately, there isn't a good hub solution that will do both. Not that I'm familiar with anyway.

Well said and I agree with your assessment.

I want to apologize for taking this thread off on a tangent since I would NOT consider the MAC a "Favorite high power hub motor" by any means even though it will accelerate faster than any motor currently available from 0-20 mph. The MAC is my "Favorite high torque hub motor" .

I'd have to go with a QS 205 for my "Favorite high power hub motor" :wink: .

 

[markz]

The highest geared motor would be the MAC.

Not true, not even close. I've seen an electric motorcycle with a geared hubbie. I haven't been able to track down the manufacturer of the motor, but once I do I'll definitely share it on the forum.

Do you think it has steel gears inside it?

 

[John in CR]

The highest geared motor would be the MAC.

Not true, not even close. I've seen an electric motorcycle with a geared hubbie. I haven't been able to track down the manufacturer of the motor, but once I do I'll definitely share it on the forum.

Do you think it has steel gears inside it?

I'm sure it does. No way they'd run a motor that size with plastic gears. I didn't take it for a test spin, so I don't know definitively though. It was definitely a geared hubbie though, because the diameter was too small to be a direct drive. For years I've been figuring someone would come out with a geared hubbie for motos...so hopefully it has no one-way clutch in there and an oil bath for heat xfer and to keep the gears quiet and long lasting. The one I saw had the 17" moto rim built on, but once I track down the factory, I hope they have a model with spoke flanges as well.

 

[MadRhino]

Of course there is a market for a powerful, reliable geared hub. Those that are available yet are toys, even the best of them can’t be fed much power and strip in a week if you beat them.

 

[Bullfrog]

MadRhino...what are you using for batteries with your Trek Session 10 and Santa Cruz V10?

Where do you mount them or are you using a backpack?

I would like to build a full suspension bike or two...possibly one for pavement and one for off road but I am having trouble finding a good full suspension frame that has room to mount a battery.

I already tried a Diamondback Catch but with the battery mounted on the bottom side of the downtube but the rear suspension flexes a LOT due to the clearances in the linkage. The stack up of the clearance gave a perception that something was loose and when pushing hard it affected the handling.

Found the Nyx frame that looks pretty good: http://www.nyxbikes.com/nyx-frames but I am trying to keep my builds looking somewhat like traditional bikes just so they don't get as much scrutiny for the local LEOs.