Thank you for all the kind comments and likes, I really didn't think that there would be very much interest here because it is just another ebike post. But I have had several direct messages as wells as a bunch of others that know me from some other forums emailing me or DMing direct from there as well, so I will try and make more time to answer all the questions I just wish there was more time in a day.
I shouldn't be writing anything here that's not already written all over ES and most members probably already know but I was once new to all of this as well and at one time it was all very confusing.
Most the questions that have been asked really come down to power. Two of the most common types of hub motors are geared and gear less or more commonly DD (Direct Drive)
There is a fairly good write up of both in the following 2 links
MAC vs BMC
The Edge 1500 watt hub motor
People keep asking me the same question that is probably harder to answer than is there life after death. Which one is right motor for me? So I will do my best to outline why I chose the two motors I use and the difference between them.
Unless your working with unlimited battery power in my opinion as all of this is. The geared (planetary) hub motors will always have more torque but they also have their drawbacks too. The geared hub motors such as the BMC/MAC or bfang 8fun all use a internal gear reduction system that gives them a lot of power and in most cases they are also lighter and smaller but they also cannot take the power DD motors can nor deliver the speed DD motors can once you get over ~48volts or 30~amps
There are also a lot of other factors that can change how these motors operate as well. Most all these motors geared, or DD also have a winding specification of "T" T stands for number of Turns or Turns around the stator pole.
More turns means more torque per phase amp (NOT battery amp). Torque per phase amp is inversely proportional to Kv. This means that more turns means less rpm/volt but more torque per phase amp (NOT battery amp).
A simpler way of saying that is 4T is more speed less torque, an 8T is less speed more torque
There are other places in these forums that explain in a lot more detail than this but lets take the BMC/MAC for example. It comes in a 6T, 8T, 10T and 12T windings and it should produce the following numbers.
12T HI-TORQUE 26mph-48v, 15mph-36v
10T HI-TORQUE 28mph-48v, 18mph-36v
8T CRUISER 30mph-48v, 24mph-36v
6T SPEED 34mph-48v, 28mph-36v
and neither of these numbers mention Battery Amps but I can tell you from my experience that the BMC/MAC needs about 30 Amps to achieve the speeds listed above. So if you do your math on that 48v x 30A = 1440 watts of power and this is the Maximum that you will get out of a BMC/MAC motor. They just were not made to handle any more power than that and if you really look close at the specs, for the most part they are only rated at 1000 watts Max, so pushing 30 Amps to these with a controller is running the motor in the red zone. However, if you are only bursting at these amps for short periods of time, then you should be fine. I put 1800 miles on my last motor with this setup until it finally quit.
Some of that info I took from here which also sells the MAC motor
Now the same thing applies to the DD motors when it comes to the "T" rating. For my example I will use some info I found on the leaf 1500watt DD hub motor which is very close to the EDGE DD motor I have and use.
The following info here is from another ES users called Neptronix. I have read many many of his posts. So should you. He outlines a lot of the pro and cons in the leafbike version of the 1500watt DD hub motor which is commonly available and fairly cheap and almost exactly what I am using for my Qulbix 76r and EBB builds.
For a 26" wheel, you will want a controller and battery capable of pushing 60 amps continuous during acceleration or hill climbing in order to hit the top speed of the motor and have decent torque.
60A x 48V = 2880W peak.
Here are some figures for speed per volt in a 26" wheel:
I measured my no load at 645rpm at 49 volts ( 13.16 kv ), so keep that in mind. By that math:
4T: 631rpm / 48v = 13.16 kv ( measurement by me, adjusted down 1 volt )
5T: 485rpm / 48v = 10.1 kv ( fluxshifter's measurement )
6T: 336rpm / 48v = 7kv ( assumption based on 3kV steps per winding )
Rough idea of 48v speeds in a 26" wheel:
4T: 39mph ( observed )
5T: 30mph ( calculated but not observed )
6T: 21mph ( assumed )
The next thing to also consider is the size of the wheel your motor is going in. The BMC/MAC has a diameter of about 172mm and the EDGE DD/leafbike 1500w is about 232mm. Using a 19inch rim vs a 26 or 27.5 rim will also affect your speed and torque as well as the size and diameter of your tires you put on top of that.
I want to also note that the BMC/MAC is about 15lbs while the 1500W DD's closer to 21lbs and some of the bigger MXUS3K and 5K Turbo are closer to 30lbs.
This is a huge fact to consider when lugging around your bike.
But back to the BMC/MAC to EDGE DD/Leaflike 1500watt motor comparison. I did a LOT of research before I bought either of these motors, probably hundreds of hours because there is really no one answer to suit everyone. There are so many factors that can affect everything. A 10T MAC in a super cheap bike frame on a 19" wheel with a 25a 36v controller will give you way different results than a 6T MAC in a nice suspension MTB frame on a 26-inch wheel using a 30a 48v controller. Just those two combinations of the same motor in a similar frame will give very noticeable difference in speed and torque as well as range.
In my best experience over the past 6 years, 6-7 of my own bikes and several observations of friends. The BMC/MAC or the 1500w DD is the best all-around motor for your average joe. Once you get beyond these, you get into a lot more money, size or weight.
48v at 30a will run either of these motors just fine for your average day to day riding and being able to hit 30+ mph
For a side by side comparison the DD takes more amps on the get go than the BMC/MAC to get similar results down the half mile flat street around the corner from me.
MAC 6T on MTB frame with a 48v 30a controller and a 48v 20AH li-on battery pack with a 50amp rating
EDGE DD on a 76r frame with a 60V 60a controller and a 60v 32AH li-po battery pack with a 100amp+ rating
In this race. The MAC will be faster right off the line however it loses strength the faster it goes where as the DD is slower off the line but still gaining speed at 30mph mark. It is also a lot smoother, the MAC is like driving a chainsaw go kart vs the DD which glides off the line and picks up speed quick. but both hit 30mph about the same place. However, I used much more than twice the power in the DD than I did in the MAC to get the same results but the bike the DD was in is also 70lbs heavier so that also has to be taken in to account.
48v x 30a = 1440 watts max 0-30mph full throttle
60v x 60a = 3600 watts max 0-30mph full throttle
So the actual winner here is the BMC/MAC but the BMC/MAC was running at 150 percent power and the DD was only running about 75 percent power. The BMC/MAC cannot sustain that power all day. The DD can.
So what did I just say there? I said that using both bikes in the configuration I have them setup in both give me similar results using the observed power I just listed above which means absolutely nothing to you unless your running the exact same configuration, controller plus motor type and model number I have.
And that is my answer to everyone that asks me which motor is better or which motor is best for me or what’s the fastest I can get or….
There are SO many variables that these questions are impossible to answer. Let’s list out the variables
Motor – Geared, Gearless – Winding (4T, 5T, 6T etc..)
Controller – Your controller should match the max power (volts/amps) your motor can take
Battery – Battery’s C rating needs to match max power (volts/amps) of controller
Size of rim and tire – a 17 inch rim will give much different results than a 27.5 inch rim using the same Motor, Controller and Battery. Smaller the rim, the more torque but less speed, larger rim, more speed less torque.
And the final variable is weight. My GT frame weighs about 38lbs. My 76r frame weighs 107lbs.
My average Wh/mi on the GT is 15, My average Wh/mi on the 76r is 35
This is a huge difference to get more or less the same comparable riding power and speeds from both bikes.
To go further into those numbers. The battery pack on my GT is a 48v-20a pack rated at 50a continuous discharge amps. The battery pack on the 76r is a 60v-32a rated at 160a continuous discharge amps.
48v x 20a = 960 watts of power total
60v x 32a = 1920 watts of power total
960w / 15Wh/mi = 64 miles of riding per charge on average
1920w / 35Wh/mi = 54 miles of riding per charge on average
So in comparison I am roughly getting the same range and power on the 76r that I am getting on the GT using twice the power.
And these numbers are conservative. If I romp on it, dog it, give it the gas or what ever you call it where your from, my Wh/mi goes up. On the GT not too much, it might go to ~23 on a hard ride where as the 76r will go to ~47 however if I ride very conservative, switch controller to 50% power, slow starts, coast when I can, etc.. I can even swing quite a bit more out of them
Using those numbers I just cut my riding range by a lot on semi-hard ride
960w / 23Wh/mi = 41 miles of riding per charge
1920w / 47Wh/mi = 40 miles of riding per charge
Or significantly increased them on a very conservative ride
960w / 13Wh/mi = 70 miles of riding per charge
1920w / 25Wh/mi = 76 miles of riding per charge
But again, the 76r is almost 70lbs heavier that the GT. It would be interesting to swap everything and see what numbers I was getting then using the battery, motor and controller on the opposite bike.
In one of my comments I was asked about, I noted I used less power using the speed switch. Unfortunately, the GT does not have this option at current, but the controller on the 76r is programmable to three different switch settings triggered by a 3-way switch I have mounted on the handlebar by the throttle. I have it configured as SW1-50%, SW2-75% and SW3-120%
What is this this 120% magic you speak of?? Some of the nicer controllers have what’s called field weakening (FOC) on the phases and the explanation of that starts to get over my head.
There is a very good article on how electric bike motors work here and you should read it but it’s more or less nitrous or turbo would be the closest quick term I can come up with
https://www.electricbike.com/motor-tech ... ms-part-1/
But back to the Switch settings. I have a normal ~18 mile ride I do most every day. If I ride the bike in full power mode I use quite a bit more energy than I do riding at 50 percent. There is nothing magic here, the bike is going slower, it’s just not enough for me to really notice on my regular ride. I can still easily hit 30mph in both modes, it’s just slower getting there at 50% power than it is at full power. My average riding speed is about 18mph on this trip, there are many starts and stops, city blocks, sidewalks, trails and paths, I get through the same ride in the same amount of time, but one uses a lot less battery power than the other because I am not wasting energy accelerating to speed each step of the way.
The real answer is, what do you want to use your bike for? If you need to commute to school or work, then design your bike that way. If you’re a trial rider and climb a lot of hills and want to do it fast, then you will need to design your bike a different way.
In my opinion, anything under a 1000watts is a waste of my time. I’m over 50. My knees hurt a lot and so I don’t peddle very much. 800-1000 watts is my average usage riding the way I ride so that is the range I am building around.
If you’re a 25mph or less kinda of guy then the BMC/MAC is probably a good fit for you. After riding mine for a few years I felt like I needed a little more at times. The 1500watt DD motor is a great motor. Depending on the manufacture like the ones from EDGE or Leafbike there are people running 4-5000 watts through the motors for brief periods of time and it’s holding up. The BMC/MAC would fry at those numbers but the great thing about the 1500w DD is that it will also run decent on as little as 36v and 20a so given what you can afford for a motor controller and battery that gives you a wide range of something to start with and upgrade to in the future if needed.
I originally wanted to go with the MXUS
3K that seemed to be the one everyone was wanting at the time but I started doing the math and I did not like the numbers. It’s a heavy motor. 30lbs. It eats a lot of power. 3-5 thousand watts or more. The battery and controller are much more expensive. Going this route with some of the numbers listed here
https://fasterbikes.eu/en/hub-motors/21 ... otors.html
3K turbo in rim 350.00
72V controller 250.00
72v 20-40amp battery pack with a hi-discharge BMS starting at 1000.00 + more like 1500.00 for a good one
Now I am already 1500-2000 dollars in just my motor, controller and battery alone producing a setup that will consume about 6000 watts of power at full throttle.
72volts at 20amps of battery is 1440 watts.
72volts at 40amps of battery is 2880 watts.
And I got this info off another members forum here on the MXUS
3K testing results
Watt Hours (wh) required per mile on flat terrain with no wind. MTB
The Average wh/mi here is 57.5 between the 4 numbers
1440 watts – 25 miles per charge
2880 watts – 50 miles per charge
And these are all conservative numbers on flat ground. So after my thinking on all of that I decided that the bigger motors were just not for me. I don’t race, I don’t motocross. I am not competing in any events. I just like to ride. The EDGE 1500 has proven to be more than enough to take me anywhere I need to go and in the configuration I am using, it has plenty of torque to take me up the steepest of hills with zero peddle.
I personally can’t find a source for the EDGE version of this motor any longer but from reading this one from Leafbike is very close to the same specs and is not a bad price for the kit and if I remember reading right the default motor winding is a 5T but other windings can be ordered if noted at time of order.
http://www.leafbike.com/products/diy-bi ... t-987.html
I also listed another link to the 1500watt DD motor I was using in the EBB Enduro. It looks and feels very same in performance and speed as does the EDGE so I would have to assume they are very similar motors. Unfortunately, my bank account has seen to many hard hits lately and I have not purchased a CA for the EBB yet. It is on my list, as soon as I get that I will be able to post some numbers from the motor I got from Ncycle used in the EBB. So far I have probably 300 miles on that bike though and it seems to be every bit as good as the EDGE and for all l know could be the EDGE under a different name or re-seller.
I have both a 6T and 8T BMC and to be honest, the 6T has way too much torque, in most instances I have pretty much quit letting people ride that bike because they kept hurting themselves. In the lightweight GT MTB frame it is almost impossible to keep the front wheel on the ground at speeds less than 5-8mph the bike will flip right out from underneath you if your not careful with the throttle.
A good place to start is the ebike simulator found here.
It will seem confusing at first but after playing around with it for a while you will be able to see the differences between the different motors and configure a bike for your needs. If you go to the motor selection and scroll all the way down there is a SHOW ALL option that will give you more motors to choose from as well as a custom option for battery packs if yours is not listed. The EDGE motor is not listed there but the Leaf 35mm 5T is and that is about as close as you can find to what I have talked about here in this article. If you spend a lot of time there you will see that most of the motors are pretty much the same.
On another note: When I first started this, I was terrified about getting a wheel that was already laced. I have since overcome that and laced several motors myself. It’s really not that hard.
There is also a spoke calculator here
You don’t need to worry about a lot of the numbers just make sure you get the ERD and flange diameter of your motor correct and all of mine have worked fine. After you get the proper length there is also a BUY NOW button so it’s a one stop shop and their spoke are quality.
Once you get your spokes, there is good information here on how to lace the wheel.
All of these I did are setup on a 1x cross pattern. I would think that with the size of the motor in a rim, a 1x patter is all there is room for.
In my next post I will describe the differenced between the 76R frame, the EBB Enduro as well as the GT and the pro’s cons of buying and or riding each of these from my own experience and I will do my best to get together a final cost analysis of the three.
I can already tell you that the Qulbix 76r is the best bike all around in my opinion. Stay tuned for why.