Good hub motors that are efficient on battery, good torque on hills, can tow, good top speed?

MarkJohnston

10 kW
Joined
Mar 25, 2021
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620
I have the 9c clone but it lacks torque on hills even with my amps at 24. It can't tow at all. It's not super efficient on battery.

I kind of want something new, hard wearing, long last lasting, maybe geared, but would I have to sacrifice the top speed of my direct drive ? Let me know. Thanks
 
Torque times speed equals power. For the same total power, if you want more of one, you're going to give up some of the other.

Leaf 1500W motors (and likely their 1000W motors as well) are available in different windings by request, at no extra cost. Higher winding counts offer higher torque per amp and lower top speeds. They don't increase the motor's maximum torque, but they do make it much easier and cheaper to approach the motor's maximum torque. They're also much more likely to run in an efficient speed range than a motor with a faster winding.

For what you want, a controller and battery that deliver more current (therefore more power) would be much more effective than switching motors.
 
MarkJohnston said:
I have the 9c clone but it lacks torque on hills even with my amps at 24. It can't tow at all. It's not super efficient on battery.

I kind of want something new, hard wearing, long last lasting, maybe geared, but would I have to sacrifice the top speed of my direct drive ? Let me know. Thanks

Get a 60A+ controller and a battery that can support it. You need higher phase amps. If you have issues with heat, then consider the bigger motor, but you'll need the controller and battery regardless, so get those first.
 
E-HP said:
MarkJohnston said:
I have the 9c clone but it lacks torque on hills even with my amps at 24. It can't tow at all. It's not super efficient on battery.

I kind of want something new, hard wearing, long last lasting, maybe geared, but would I have to sacrifice the top speed of my direct drive ? Let me know. Thanks

Get a 60A+ controller and a battery that can support it. You need higher phase amps. If you have issues with heat, then consider the bigger motor, but you'll need the controller and battery regardless, so get those first.

Ok so just do a better rebuild? I have about 500 18650 sanyo cells. Just need a spot welder or whatever right?
 
Do you recommend any frames for carrying a 48 volt 60 amp battery? I want to build the compartment on the mid tube but that would be a very large and heavy battery and most bikes don't have room to accommodate that.

I was thinking maybe an old school steel beach cruiser, I definitely want something more beefy. I.e. the metal tubes themselves should be extra thick and steel. I'm going to want to drill a bunch of m6 holes and use SS bolts with lock nuts and maybe 10 of them for that big old battery. not sure if that will make the frame dangerous and more prone to breaking
 
If your sanyos are capable of 10A each, get a couple of reention Polly cases that take 70 cells each for 14s5p and build yourself 2 interchangeable batteries. Then shunt mod a 40A controller to 50A; that will give you 2500W which will get you up the hills no worries!
 
You seem gradually headed to where I ended up. Steel bike meant I could modify it, adding disc brakes, and make it 6" longer. 6-1-2015  Schwinn Cruiser with 52 t crank.JPG

Lengthening a cheap beach cruiser made it able to carry multiple large batteries. A larger hub motor made it able to tow loads up hills. The big motor is more efficient towing because its not overloaded. Overloaded motors of any type just heat up, and possibly melt as they rotate too slow.

Big motor keeps going up the hill faster, above 15 mph, avoiding the low rpm overloaded heat up. So you don't waste your battery making things hot. It also goes fast on the flat. 52v running a 40 amps controller is plenty with a big motor. But at times I did run this bike on 60v, making it a zippy bike for keeping up with traffic on big city streets. In the lane, not the bike lane.

None of this going fast is less energy than going slow though. The max efficiency is going slow, particularly in a low gear with a mid drive. But you mentioned going fast as a priority of your build.
 
Well the one I just bought was stolen. frocking porch pirates. Mightve been one of my shady neighbors. :x
 
Every now and then, those type of bicycles go for uber cheap, like $50, they are usually s/s or 3 spd igh.
Problem I see with most of those are the coaster brakes, means there are no disk brake mounts or v-brake mounts and you have to change out the fork to get brake mounts which means your left without a rear brake which isnt that bad if your riding slower speeds, front brake is plenty enough.

I had always thought even the igh were 100 or 110mm, until I checked out a bike like yours going for $80, igh, Nexus came to 125 or 130mm dropout width. Its a bike that got away from me, I should have got it. The thing I hate about those bikes is the sweeping loop of the bars that takes up to much space inside the triangle for a battery for a commoner like me.


dogman dan said:
6-1-2015 Schwinn Cruiser with 52 t crank.JPG
 
MarkJohnston said:
Well the one I just bought was stolen. frocking porch pirates. Mightve been one of my shady neighbors. :x
What????? How? Was it locked? That seriously pisses me off. :evil: If you have the serial no. and photos post it as stolen on bikeindex.org.

calab said:
...which means your left without a rear brake which isnt that bad if your riding slower speeds, front brake is plenty enough.
He's got long steep downhill sections, remember? That's what started all this...
 
I can try. Only so much a Chinese drop shipper will do though. I have renters insurance though and can maybe claim through UPS. I'll reserve a charge back for worst case scenario
 
Re cruiser type bikes. The reason I chose a cruiser for that longtail build was simply because it was steel. Yes, just a coaster brake, but welding a disc mount on the forks was easy, and so was adding disk mount to the rear, as well as towing mounts for a bob tail trailer.

But yeah, many people don't weld at all. I myself weld extremely poorly, but my construction experience makes it easy enough for me. Measure and cut being the hard part.

If you look at 7 speed cruisers, they at least have rim brakes, and the crucial front disc brake can be had by a fork change. The bar blocking the middle of the bike can be simply cut away if you want to put a battery there.

But my basic point remains the same, if you want to carry a big ass battery, it helps to start out with a cargo bike of some kind. The longer frame allows more stability at speed than common for a cheap mtb, and you can put a crapton of watt hours in a pair of sturdy saddle bags. Then that big heavy battery can easily power up a motor big enough to get up hills with decent efficiency, and speed.
 
dogman dan said:
.
. Then that big heavy battery can easily power up a motor big enough to get up hills with decent efficiency, and speed.

What about overheating the hub motor? Gears help with hills and make battery life more efficient
But DDs are more efficient on the flats? Why do they say new factory made ebikes are much more battery efficient than home brew? Maybe like Chalo was saying that they don't use 18650 cells or maybe different higher quality cells that are lighter. E Motorcycles are cars use a different kind of battery system altogether I've noticed
 
MarkJohnston said:
Why do they say new factory made ebikes are much more battery efficient than home brew?

Who says that? People who are trying to sell factory made e-bikes?

There are ways to set up your bike conversion wrong, and get poor efficiency, but you don't have to do that.
 
Hey, a little bit of tanget kind of but I'm using my regular push bike and it has normal v brakes that ARE VERY GOOD. I can pretty easily lock up a tire with these. I wonder why these are so good? What's with the housing cover? I love my brakes to lock up and barely take any effort when pulling the lever :twisted:
 

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I'm f'ing jealous, brakes pfffffffffffft
Why use rubber when you can use electrons?
pic, rear hub?

MarkJohnston said:
Hey, a little bit of tanget kind of but I'm using my regular push bike and it has normal v brakes that ARE VERY GOOD. I can pretty easily lock up a tire with these. I wonder why these are so good? What's with the housing cover? I love my brakes to lock up and barely take any effort when pulling the lever :twisted:
 
MarkJohnston said:
... ARE VERY GOOD. ...

....easily lock up a tire with these. :twisted:

Locking up a tyre is by no means a good way of estimation of the power of a braking system.

You will take longer to stop, any time a tire lock up and slides. Just look at ABS braking systems and some of the inherent complications surrounding the design of such... with mindful relation to time and force and speed. ABS will stop you faster in an identical bike, than one with the ABS switched off... Given identical reaction times and initial velocities.

Brakes use power.

We know what power is. Force and mass. That stuff. All those physics and stuff. Taming them wild horseys.

Horsepower.

A good brake system does not lock up.

A good brake system has enough power to keep the bike slowing down ( win) while not locking up ( fail).

A good brake takes most of the speed out of the rolling mass. The instant it locks up, it has failed to perform ( " unloads"). Locked up brakes have nothing to do with ( momentary inertial) power, they just have the friction of the road to the tire... and that turns to smoke and liquid rubber really gfast.. and smokey liquid rubber is not very... quick to slow you down.

Quite the opposite, actually. Locked tyre sliding with momentum and an initial velocity? Slide a mile on grass, slide 10 on glass.. slide till you hit something stationary while you are sliding, locked, on a film of melted rubber.... OR.... slide ten feet in friction filled sandtrap.... to outbrake.

Its a coefficient of friction.

Good brakes? They ( It ) takes the top 75% of the speed off the momentum, first, then takes its time with the last 25%... or so.. like a radial mounted floating 320mm pair of superbike rotors... with the right master and stainless ( hard?) lines to back it up...

A bad brake system takes 25% of the top end.. and takes its time with the last 75% fof the speed... because it cvould not sustain the power needed for deceleration, rotors overheated.. and .. and or locks up ... ect. Wham.


Its power. Takes power to go fast.. and... takes even more power.... to slow down fast. Takes a hellubvalotta power.


Galfer makes a 242mm bicycle rotor.
 
I dont know how much power the e-brakes work on my generic, it doesnt feel like regen as I gain no mileage, ever.

It rained once and I could feel a shock when I had the gnd taped to the steel handlebars for Low-Brake, where I'd touch the other wire in the vacinity and the brake would kick in, the application was akward, experimenting as they say, more literally, laziness.
 
MarkJohnston said:
.... like Chalo was saying that they don't use 18650 cells or maybe different higher quality cells that are lighter. E Motorcycles are cars use a different kind of battery system altogether I've noticed


I have used recycled EV cells since day one, also. I find them a much better option, recycling highway grade EV cells for my e-moto projects. I wont use an 18650 for any build.


calab said:
I dont know how much power the e-brakes work on my generic, it doesnt feel like regen as I gain no mileage, ever.

Braking force is directly proportional to speed. Maybe you are not going so fast as to require significant power to stop?
Maybe.. Maybe.. you do not have much weight, mass in rotational inertia. You can have a 15lb hub motor.. and you can have a 30 lb hub motor.. and the 30lb hub motor will make more power when it stops int he same distance as the 15 lb motor ( takes, uses, gave)... More rotational mass.... ( think: Flywheel )

This link is great. Especially " Hint 4". Gotta love that " inverse logarithm".
https://physicstasks.eu/277/a-car-and-the-stopping-force-directly-proportional-to-its-speed
Hint 4 - the time at which the speed of the car is half its initial value

You are looking for the time when the speed is equal to v*0/2

. You know how the speed depends on time.
Solution of Hint 4 - the time at which the speed of the car is half its initial value

Stopping force calculators are all over the web. I am going to go buy myself a Wave® Rotor in 246mm x 2.3mm. I'll stop ranting about.. brakes..and brake horsepwoer.. and.. stopping.. and.. and get back to hub motors...

carbrake.jpg
Another great ink.
Since the power of brakes is hugely underestimated (the brakes of an average Ford F150 for example, can generate over 1000 brake-horsepower), I thought of BrakePower.com.

https://brakepower.com/about-brakepower.htm
 
MarkJohnston said:
Hey, a little bit of tanget kind of but I'm using my regular push bike and it has normal v brakes that ARE VERY GOOD. I can pretty easily lock up a tire with these. I wonder why these are so good?
You were under the (common) false assumption that disc brakes are necessarily better stoppers than rim brakes.
 
99t4 said:
MarkJohnston said:
Hey, a little bit of tanget kind of but I'm using my regular push bike and it has normal v brakes that ARE VERY GOOD. I can pretty easily lock up a tire with these. I wonder why these are so good?
You were under the (common) false assumption that disc brakes are necessarily better stoppers than rim brakes.

Dunno. What about cable stretch? I think these are better because the brake cable is housed completely. Correct me if wrong. Only problem with v brakes is they are kind of a lost art, hard to find comprehensive information on the internet about them.( They are tricky ASF to get right)

Disc brakes are new, and I have a plethora of info on my hope tech v4s dh .
 
Can anybody explain the spacing arrangement ?
 

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MarkJohnston said:
Can anybody explain the spacing arrangement ?

It's pretty self-explanatory. You want the brake arms to be more or less vertical and with adequate clearance from the tire when the pads contact the rim. For that reason, the spacing must be changed to reconcile different rim widths and brake pivot spacings.

The convex washers go on either side of the brake arm, to form a ball joint for aligning the pad to the rim.

For the most spacing, you use the thick concave washer plus the flat washer between the pad and the arm. For the least spacing, you use the thin concave washer between the pad and arm. There are two other combinations that give you intermediate spacing.

If you still don't understand, have a professional set up your brakes. Don't insist on getting in his or her space and watching. If you want that, watch YouTube videos about it instead.
 
Perahaps that be the case, it probably is because I get even less mileage when I do more steep hills but the e-brake-low system of the generic works good enough for braking, still require emergency stopping powers of the brake levers preferrably a front if you only have one to choose from but a rear wouldnt stop me from heading out, knowing how personal one on one I am with my machines, I dont name them..... yet.
 
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