Most powerful rear hub motor for 135mm MTB frame?

ebike11

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Just wondering what options there are.
Looking for the fastest rear hub motor that can fit in a standard MTB frame on 84V.
Thanks!
 
Likely the easiest to find would be the larger crysalyte motors, using the faster wind for more speed per volt.

See them at Grin Technology, and buy there too if you live in north America. You live in Korea though, so look for similar motor in china perhaps.

The popular huge muxus of course is not 135mm. ( 145mm I think) Get that, and a steel frame. Bend the steel frame out 5 mm per side easily. The big muxus is what you want if you really want to run motorcycle like power.
 
Get a bike with steel rear dropouts and don't worry about the dropout width as it can easily be widened to 150mm or more. Then your motor options are limitless.
 
My CroMotor has a 135mm axle. It is very tight for a rear brake, so I use variable regen/ebraking for rear brake instead (and it works great) and only have room for a single rear sprocket. I use a two speed crank to give me two pedaling speeds, my frame won't take a chainring set. My frame is not MTB, but the width is 135mm. I also use dual front disc so there's plenty of mechanical braking. Setup is described in the Borg thread in my signature.
 
Cromotor is going to be the most powerful at 135mm. But "most powerful", "fastest", and "best" aren't the same thing.
Smaller motor might be faster depending on the wind, the aerodynamics, and the riding conditions. One of the big Clytes might be better if you plan to haul weight or are going to be using the motor deep in it's torque band.
 
dogman dan said:
The popular huge muxus of course is not 135mm. ( 145mm I think) Get that, and a steel frame. Bend the steel frame out 5 mm per side easily.
Or file / grind the axle flats further down past the shoulders, and use spacers around the remaining unthreaded axle that sticks out past the dropouts, so the nuts apply their pressure to the dropout face as normal.

Worked fine for me. ;)

How far you can go depends on the specific motor and the width of your cassette or freewheel. I used a singlespeed freewheel, so I can go pretty far.

https://endless-sphere.com/forums/viewtopic.php?f=2&t=67833&hilit=+mxus+axle+flat*&p=1249555#p1247658
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amberwolf said:
dogman dan said:
The popular huge muxus of course is not 135mm. ( 145mm I think) Get that, and a steel frame. Bend the steel frame out 5 mm per side easily.
Or file / grind the axle flats further down past the shoulders, and use spacers around the remaining unthreaded axle that sticks out past the dropouts, so the nuts apply their pressure to the dropout face as normal.

Worked fine for me. ;)

How far you can go depends on the specific motor and the width of your cassette or freewheel. I used a singlespeed freewheel, so I can go pretty far.

https://endless-sphere.com/forums/viewtopic.php?f=2&t=67833&hilit=+mxus+axle+flat*&p=1249555#p1247658
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file.php

Oh do you mean you filed down a 145mm axle to fit on a 135mm frame?
 
With big motors, you have to make torque plates or custom dropouts anyway.

I’d say most big motors can be fitted pretty easy.
 
MadRhino said:
With big motors, you have to make torque plates or custom dropouts anyway.

I’d say most big motors can be fitted pretty easy.

Yes i see....but i have access to tools or services where i am to do that type of modification...so im looking for the largest possible motor for standard MTB dropouts.
Looks like Cromotor so far
 
Wow thx AW, never seen that before, its great for my rear motor that I want to fit up front, been scouring the interweb for fat forks, pondering alum weld current front fork, Townie's an odd ball, going 2wd myself, all my motors are rears, dont wanna buy weaker narrow front.
amberwolf said:
dogman dan said:
The popular huge muxus of course is not 135mm. ( 145mm I think) Get that, and a steel frame. Bend the steel frame out 5 mm per side easily.
Or file / grind the axle flats further down past the shoulders, and use spacers around the remaining unthreaded axle that sticks out past the dropouts, so the nuts apply their pressure to the dropout face as normal.

Worked fine for me. ;)

How far you can go depends on the specific motor and the width of your cassette or freewheel. I used a singlespeed freewheel, so I can go pretty far.

https://endless-sphere.com/forums/viewtopic.php?f=2&t=67833&hilit=+mxus+axle+flat*&p=1249555#p1247658
file.php


file.php
 
markz said:
Wow thx AW, never seen that before, its great for my rear motor that I want to fit up front, been scouring the interweb for fat forks, pondering alum weld current front fork, Townie's an odd ball, going 2wd myself, all my motors are rears, dont wanna buy weaker narrow front.

Just keep in mind you'll have a very long axle stub sticking out each side of the front fork, with a stack of washers between the threaded area and the fork dropout face. Might look like something from Ben Hur. ;)
 
I've been considering this one for a while:
itr7oQ4lG5jt1sOt0jpCk-lgVBZv4SQic-sax8w7SNlm1RLeRiJe28OP649wCRsu1SxgV_1upYlpjfwMANocDnfj6vb2UUiDACGg8rQ74sM_8OgVwDJuNSU3SlRFm0NrKM6HAE9Guy7rZ2LE8BPrmIFf1d7BBIdnu9rNI50HXs5ySBsD5SJ9tuki0HB7ffbbTwwKj7S4WUmzn_64So6ywfcLfeenjo21vJtjcpWeIR246LYBUsNDsRsk4bQZsUEV7_CkXeAWKItgmQwZmxR-AmD4N9Yx0VedLuDcHkgYkhZ74B0VkaqpTzvuZDSfpIDjpMAqbnstTx8fmu8m2caMRZ8Ply7oF0qkz7MpTkYPPmXhDLQZDvksxNDycHuDiscDttq3CbJkMu43XDnC7YIOSyPAjIkxFHutc-LjMHf63kZiL0HmqQwLdkzV79TC2r0Hb-5-ckab63EkEA1egp_7znyiSQ6YcZXswV_79zv_hRIqRLGBRzEy2Gs8Kby9PgMF3qw1cm2QycGOBoVIlMj0QcUDUsoHuAU1bKbGaEEae0hqbvQMdbyAXz6Bvzxp-z66TiQ_25C_DRgS_fVKdYnVsPR475hloiXf0A4xuB7IZuM=w1225-h567-no


https://www.aliexpress.com/item/Standard-135mm-dropout-M16-Screw-MXUS-V3-3000W-brushless-no-gear-hub-motor-for-rear-electric/32761513299.html?spm=a2g0s.8937460.0.0.2bVycJ
 
You could look into buying a front hub motor and using a rear hub motor to get more power. For instance a QS or mxus 3kw direct drive rear, with a d.d. 9c clone up front. Geared motors like the MAC from em3ev are pretty powerful. Can use the motor simulator at www.ebikes.ca and you can click the ADD button for 2wd.
 
Yes, with a single speed instead of 7 gears in back, lots of room to change the axle.

I just meant to say that if you want all 7 ( or 7 of 8)gears, a large crystalyte fits fine in regular bikes. Ok, so 3000w is lame these days, but I get all I need out of 2000w or so. Running 60v, my cargo bike with an old 5304 clyte can hit 35 mph easy, and with tailwind even 40 mph, with 1800w continuous. It will climb any paved mountain road in my state, towing a trailer too. I can also dial up to 3000w, with a CA adjustment, and 72v battery.

The newer big crystalytes should be able to handle 4000w in bursts. And get you top speeds near 50 mph with 84v. Again, just get the faster wind for the most speed per volt.

In general, you can also flex out most alloy frames to 140 mm, just 2.5mm of flex per side. So cramming in a big motor might only need a minor grind to the axles to make it go. If possible, just make some bolt on torque plates that allow a wider motor, with gears, and lengthens the rear 5 or 6 inches.

If fast and cheapest is your need, then you are looking at the muxus, single speed gear, and up voltage till you are stupidly fast. grind it to 140 mm, and cram it in.
 
I think you're going about this the wrong way. If you want power you need a custom swingarm to support a scooter hub. Since it's custom you can make the size and geometry whatever you want.
 
amberwolf said:
dogman dan said:
The popular huge muxus of course is not 135mm. ( 145mm I think) Get that, and a steel frame. Bend the steel frame out 5 mm per side easily.
Or file / grind the axle flats further down past the shoulders, and use spacers around the remaining unthreaded axle that sticks out past the dropouts, so the nuts apply their pressure to the dropout face as normal.

Worked fine for me. ;)

How far you can go depends on the specific motor and the width of your cassette or freewheel. I used a singlespeed freewheel, so I can go pretty far.

https://endless-sphere.com/forums/viewtopic.php?f=2&t=67833&hilit=+mxus+axle+flat*&p=1249555#p1247658
file.php


file.php

Thx this is a great idea..i already bought the 135mm Mxus version though that fits perfectly since i am using a single speed freewheel.
Not the sure of the power differences between the 135mm and 145mm though.
Maybe next motor will be 145mm with a filed down axle like this.
 
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