Building a Powerful Ebike

General Discussion about electric bicycles.
Callbrin   10 mW

10 mW
Posts: 34
Joined: Sep 03 2018 1:41pm

Re: Building a Powerful Ebike

Post by Callbrin » Jan 16 2019 11:50pm

if anything I'll upgrade the battery and the motor at some point as well to one from maybe leafbike/motors

Callbrin   10 mW

10 mW
Posts: 34
Joined: Sep 03 2018 1:41pm

Re: Building a Powerful Ebike

Post by Callbrin » Jan 21 2019 3:58am

also Im confused about the windings but for me weighing as much as i do should I go for a speed winding or torque and what windings are for speed like 16x4t vs 7x9t

ScooterMan101   1 MW

1 MW
Posts: 1724
Joined: Oct 06 2012 4:45pm
Location: South of San Jose, California.

Re: Building a Powerful Ebike

Post by ScooterMan101 » Jan 21 2019 6:28pm

Depends on the Wheel Size and if you live in a flat area or an area with hills.

There is the Grin Motor Simulator Tool to help ( as long as they list the motor you are interested in )

Others here can tell you about the spec's of the heavy DD hub motors as I still use lighter weight geared hub motors.

Callbrin wrote:
Jan 21 2019 3:58am
also Im confused about the windings but for me weighing as much as i do should I go for a speed winding or torque and what windings are for speed like 16x4t vs 7x9t
My first conversion ...

https://endless-sphere.com/forums/viewt ... 1#p1077497

It's 2018 already, lets get some real , improved e-bike / e-velomobile / e-motorcycle designs .

Callbrin   10 mW

10 mW
Posts: 34
Joined: Sep 03 2018 1:41pm

Re: Building a Powerful Ebike

Post by Callbrin » Jan 25 2019 7:16pm

ok so i got some new info.


1st i wont be going 65mph on a bike, 40 would be my max
2nd I'm going to upgrade to this motor https://www.leafbike.com/products/e-bik ... l-991.html but I dont know what type of winding I should get because i still want to at least be able to go around 30-35mph but have plenty of torque so what winding would be the best compromise?

3rd what type of controller should I get? bluetooth? my current batter pack is 52v 20ah

also my current motors efficiency tanks when I go the max speed. i.e. about 18mi full speed on a full charge and around 45mi when i limit it to around 18-20mph

E-HP   100 W

100 W
Posts: 165
Joined: Nov 01 2018 9:20pm

Re: Building a Powerful Ebike

Post by E-HP » Jan 25 2019 9:23pm

Callbrin wrote:
also my current motors efficiency tanks when I go the max speed. i.e. about 18mi full speed on a full charge and around 45mi when i limit it to around 18-20mph
Might not be just the efficiency. It takes roughly twice the power to go 25 mph vs 18 mph, for example. That equates to a 38% increase in energy consumption per mile, which accounts for a significant part of the difference.


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donn   100 W

100 W
Posts: 188
Joined: Aug 13 2018 10:30am
Location: Seattle

Re: Building a Powerful Ebike

Post by donn » Jan 25 2019 9:53pm

Right - that's wind resistance, different kind of efficiency issue. No motor can overcome that problem.

For another example, according to ebikes' simulator, if you go from 20mph to 30mph, you'd expect the same loss of mileage you're describing, and it doesn't make much difference which motor you use. That's why electric motorcycles have to pack those big batteries.

markz   100 GW

100 GW
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Joined: Jan 09 2014 11:38pm
Location: Alberta Canada

Re: Building a Powerful Ebike

Post by markz » Jan 26 2019 3:47pm

Smaller Diameter Wheel means slower speeds, but higher torque, cooler running controller.
Larger Diameter Wheel means faster speeds, but lower torque, hotter running controller.

Low Turn Count Motor means Higher Kv (rpm/v)
High Turn Count Motor means Lower Kv (rpm/v)

There is a balance, and its recommend you think about what you will be riding whether it be steep hills, stop and go traffic, flats, 40% traffic and 60% hills, or what have you.

Lots of people move over to a 17" scooter rim which is 20" bicycle rim, or a 19" scooter rim which is 24" bicycle rim. Scooter rims are heavier in weight, and heavier duty, requiring special spokes. 1.60 width is common for scooter rims, then there is 1.85 and it goes wider from there.

Smaller Diameter Wheel, means you should get a Low Turn Count Motor to keep your speeds up.

Callbrin   10 mW

10 mW
Posts: 34
Joined: Sep 03 2018 1:41pm

Re: Building a Powerful Ebike

Post by Callbrin » Jan 27 2019 3:22am

I see, I didnt realise that it takes THAT much more power just to go a few miles faster. So then by that I would be guessing upgrading the motor to one on leafmotor is almost pointless.

So i guess the only thing I really would need is a battery upgrade in the future

also is there a chart or something to see what I would get with certain windings for speed?

I get that with less turns the torque decreases [and speed increases] but by how much? like a 16x4t vs 9x7t

Callbrin   10 mW

10 mW
Posts: 34
Joined: Sep 03 2018 1:41pm

Re: Building a Powerful Ebike

Post by Callbrin » Feb 18 2019 6:29am

im planning to upgrade the battery in the future maybe 6 months to a year so i decided that i would also upgrade the motor at the same time so for the battery placement i am planning to make 2 36v batteries packs wired for 72v on a cyclone kit (i dont plan doing anywhere near max speed on this thing im not ready to die yet) but for the battery placement i current have this pannier: https://www.amazon.com/Roswheel-Multifu ... ay&sr=8-14 and thought what if i put each 36v battery on the side (yes it would fit) also the top downt secure very well so thats outta the option. doing this thought obviously leaves the battery vulnerable to impacts if any and i want to reduce that chance and also make it safe since i plan on making it very high amperage so what would be the best way to protect the battery. also what controller would be a good choice for high amperage. This probably sounds like a stupid idea but i still want to see if i can do it, in the future of course.

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