New build, BHT mid-drive "direct", custom frame

Discussions related to motors other than hub motors.
This includes R/C motors, botttom bracket, roller and geared drives.
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Overclocker   10 kW

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » Apr 17 2017 11:23am

did some weight optimizations and removed the gold color from the hub

now doing CAD (cardboard aided design / compass aided design) for the aluminum sprocket spider:

Image

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » Apr 30 2017 12:38pm

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i welded the original motor sprocket and a 13t 420 motorcycle sprocket together :roll:

rear hub is done, except for paint. that's a 53t 420 steel sprocket that's mounted to an aluminum carrier

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Re: New build, BHT mid-drive "direct", custom frame

Post by ScooterMan101 » Apr 30 2017 2:37pm

Are you going to be charging the Battery Pack, through the Balancing Wires ( 18 wire/JST-XH Plug ) ?
or
Through the Main Discharge +/- wires ?

What size wire ( Awg ) did you use for your custom JST-XH Plug and Wires ?

Looks like you made your own JST-XH plug by cutting one and splicing it in between the others.


Overclocker wrote:finishing pack 1 of 2. 17s6p. no BMS, shown here w/ 18-pin balancing port. sand-filled 40A slow-blow fuse

Image
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 .

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » May 01 2017 5:09am

ScooterMan101 wrote:Are you going to be charging the Battery Pack, through the Balancing Wires ( 18 wire/JST-XH Plug ) ?
or
Through the Main Discharge +/- wires ?

What size wire ( Awg ) did you use for your custom JST-XH Plug and Wires ?

Looks like you made your own JST-XH plug by cutting one and splicing it in between the others.
glad you noticed the fatter balance wires, for faster balancing. i'll be charging through the main. not sure what AWG, just use the fattest that'll fit in the perf board

yes it's a DIY connector. i simply plug a typical 7-pin connector (w/ the locking lugs removed) into any point along the 18-pin array for monitoring/balancing

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Re: New build, BHT mid-drive "direct", custom frame

Post by nutnspecial » May 01 2017 6:00am

Looks good man, I like the heavy drivetrain! What max speed are you shooting for? 17s and 17in moto @ 4:1 should be around 33mph (and ALOT of torque with 18fet)! I'd try up around 80amps if the controller is cool with it, but you'll probably keep the phase amps around 2:1 unless the ride is really heavy/big/stout. Even 200ph was ridiculous on mine lol.

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Re: New build, BHT mid-drive "direct", custom frame

Post by skeetab5780 » May 01 2017 9:04am

Nice progress on the hub assembly! That thing is going to be a torque monster

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » May 01 2017 11:09am

nutspecial wrote:Looks good man, I like the heavy drivetrain! What max speed are you shooting for? 17s and 17in moto @ 4:1 should be around 33mph (and ALOT of torque with 18fet)! I'd try up around 80amps if the controller is cool with it, but you'll probably keep the phase amps around 2:1 unless the ride is really heavy/big/stout. Even 200ph was ridiculous on mine lol.
yeah it's overkill. i could probably shave some more weight from the steel 53t sprocket but i'll probably do that later. i decided to use heavy #420 because i need this thing to ride through a wide riverbed of loose volcanic ash to get to my favorite trail. so with this setup i'll probably not have to worry about drivetrain wear for a while

Image

id be happy with 45 to 50kph. i'm not too sure about that "percentage when loaded" term which defaults to 70% so your estimate is most likely more accurate

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » May 01 2017 11:11am

skeetab5780 wrote:Nice progress on the hub assembly! That thing is going to be a torque monster

Image

next step is the swingarm

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Re: New build, BHT mid-drive "direct", custom frame

Post by nutnspecial » May 01 2017 2:34pm

28mph
I was just guessing w/33mph. That 70% "loaded" is getting close to the highest efficiency and the torque fall off (~85% rpm imo), so if that's your target speed you'll be happy. The motor will get to 100% pretty quick though if you give it the power, and that looks like nearly 40mph based on the calc :twisted: !!

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » Jun 11 2017 1:18pm

Image

any comments on geometry etc?

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » Jun 12 2017 12:49am

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two 17s6p

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Re: New build, BHT mid-drive "direct", custom frame

Post by minde28383 » Oct 02 2017 5:48pm

How is it going? Update us.

I'm on the verge to buy pit bike components for rear wheel from CN.
CNC alum rear hub 32 holes - 40usd
alum rim 17'' 1.6width 32 holes -35usd
spokes, and tyre will get locally for 25usd
but i see a lot folks to using bicycle components therefore it's hard to justify additional weight using pit bike components.
ebike build in progress
CN 5.5kw scooter (on sale)
E Mindless Maverick Talisman longboard, 2.2KW motor, 150Amps controller (on sale)

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Re: New build, BHT mid-drive "direct", custom frame

Post by minde28383 » Oct 02 2017 6:03pm

My 17'' tyre and 26 wheel sketch looks even less proportional.

rear: 572mm 70/100 Duro 17''
front: 700mm 3'' 26 Kenda Flame

I may switch front rim to 24'' or might increase rear wheel. Not sure which way it might turn.
Attachments
17 26.JPG
17 26.JPG (28.35 KiB) Viewed 2402 times
ebike build in progress
CN 5.5kw scooter (on sale)
E Mindless Maverick Talisman longboard, 2.2KW motor, 150Amps controller (on sale)

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » Mar 09 2018 12:28am

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i've decided to mount the motor on the swingarm but still coaxial w/ swingarm pivot

testing the drivetrain. it's quieter than i expected :roll:


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Re: New build, BHT mid-drive "direct", custom frame

Post by minde28383 » Mar 18 2018 8:00am

The noise is not too loud indeed; it is very silent on low RPM, alnost no sound, so you can crall in low speed like with hub but not generating as much heat in the motor. The sound is not too loud because it's is low kv motor. If it was twice kv it would be a lot noisier.

I have option to use 70kv motor and I tend to use it with 8M belt over 420 sprocket. The problem is that rear pulley has to be over 100teeth with 22'' diameter (17'' mc wheel) wheel taking into account that front pulley is 22teeth. And pulleys are scarce and expensive due to their unpopularity. I believe things might change if we are lucky but it's not up to us. Masses control a market. QS is manufacturing pulleys with 103 teeth but they are for 12'' scooter rims, with flanges.
In recent few years, I found the only one used Zero rear 130teeth pulley which cost over 100eu. That's how popular rear pulleys are in second-hand market.

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » Mar 18 2018 10:30am

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should be welding soon. i modified the design yet again :lol:

motor's gonna bolt onto that plate. chain tension adjustment by moving motor forward/back. greatly simplifies the rear axle parts

swingarm-mounted motor also eliminates chain growth issues

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Re: New build, BHT mid-drive "direct", custom frame

Post by minde28383 » Mar 18 2018 10:43am

how much you pay (in usd or euros) for your rear hub? Can I see it for sale on some web shop?

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » Mar 18 2018 11:04am

minde28383 wrote:
Mar 18 2018 10:43am
how much you pay (in usd or euros) for your rear hub? Can I see it for sale on some web shop?

it's an aftermarket hub for a certain 150cc motorcycle. i purchased it from a local shop, not online

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Re: New build, BHT mid-drive "direct", custom frame

Post by minde28383 » Mar 18 2018 4:23pm

I see, but how much you paid for it?

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » Mar 18 2018 8:49pm

minde28383 wrote:
Mar 18 2018 4:23pm
I see, but how much you paid for it?
probably something like us$25

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » Mar 29 2018 8:44am

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » Mar 30 2018 10:08pm

skeetab5780 wrote:
Mar 30 2018 8:44am
Nice fab skills man, looking really nice

Image

i'm getting concerned about the strength of my motor mounting plate. it's 2.8mm mild steel. you think it'll hold up?

i think you had you had issues w/ bending your motor mounts in one of your vids

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Re: New build, BHT mid-drive "direct", custom frame

Post by skeetab5780 » Mar 31 2018 7:10am

Ehh its a bit thin now that I notice there are slots cut in it, at first glance I figured it would hold up. Maybe double it up or add some bracing underneath if you see it flex

I bent the aluminum mounts on the motor itself because they weren't completely seated on a steel surface. The bike also weighed a ton

Swing is looking really nice, how do you adjust the rear wheel/chain slack?

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Re: New build, BHT mid-drive "direct", custom frame

Post by Overclocker » Mar 31 2018 10:21am

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i'll add some gussets to stiffen it up

the motor can slide forward/back to adjust chain tension. i probably have to torque those bolts really hard though to keep the motor from "creeping"

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