KMX Typhoon midmount Minimonster 2 speed hub motor

[Trilska]

Hello endless-sphere

This is the introduction for my upcoming summer project. A project I party take on as a reward for myself since my studies are finally going decently (studying electrical engineering, and in writing moment no exams behind me). Another factor is that I have not been able to find job for the summer break. So I have a huge amount of time to kill and some saved up money from my time in the military. So after mostly lurking around on the forum for two years I am finally ready to start.
My platform, a Kmx Typhoon I bought new, I have put around 2000km on unassisted over the last year, and I must say I do not exactly regret the desiction to purchase it, and I secretly planned to electrify it from the start.

So here is the target for the project.
Range: 50km at 40km/h
Speed: Quick to 50km/h so geared for around 55km/h on nominal battery voltage
Overall build quality: I plan to use this project as a demonstrator of what I am capable of, both in the terms of my on-going education and what lies outside it.
Weight: Not critical but I would like the electric drivesystem to be under 20 kg.
Sound: Dead quiet,

Components most of it yet to be ordered, feel free to ask or give your point of view to the components or the system in questions

Bike KMX Typhoon
Wheels: 305 (16'') front 406 (20'') read. Using the stock big apple tires (quite worn after a year and 2000km unassisted, planing to replace with hookworms)
Breakes: Stock works ok but require a lot of service to maintain balance between the tires. Planing to replace.

Motor: A two speed hubmotor suplied by John in CR http://endless-sphere.com/forums/viewtopic.php?f=31&t=40859
To use in a midrive configuration. The motor is just big enough to fit between the seat and rear wheel.

Vital stats:
Rated power- 2500W at 72V
Kv- 17rpm/v in high 9rpm/v in low
No load current at 75V- 0.9A in high 0.35A in low
Hall sensor angle- 120°
OD of motor shell- 173mm (6.8") exluding rim flange
Stator diameter= 150mm (5.9")
Stator width (motor length)- 50mm (2")
Weight- under 10kg (about 8.5kg trimmed down for mid-drive use)
John in CR

Controler: Jet to be decided, hopfully the compatible sinwave controler that John in CR are working on. 100V components around 50-60A

Gearing:
I plan to utilize a belt drive based on 8mm HTD to gear down the motor 2.1:1 (38t front, 80t rear). I will CNC the pullies myselfe. A 20mm wide belt will have just enough clearance between the tire and frame. Last i plan to utilize the two speed gearing to shift the efficiency band to a lower speed for steep hills and or heavy loads, the low speed will also enable the use on normal roads with power limited via a CAv3. Shifting betwene the two speeds will in the end be handled via a microcontroler and a servo, with the shift point depending on speed and if max thrust is required (more than half throttle) och efficiency (under half throttle).
I wish the system to freewheel so a White industries eno will be mounted in the front pulley.



Battery:
24s lipo. (Before you say anything, i know it is on the edge for the 4110fets etc, but it should probably be ok with a high inductance motor, 240uH in high, And if it breaks i will have to learn how to fix it. )

89V nominal utilizing 6s turnigy 20C bricks. either 10 or 15 AH to be desised with a total capacity of 890wh or 1335wh.

BMS: Founding power programmable BMS with throttle intercept (LY.CS-bms).
http://endless-sphere.com/forums/viewtopic.php?f=14&t=40774
Probbebly a little to high energy consumption in passive mode, but enables the use of a monitoring display with temperature probe. A good idea for the control freak.

Breaks: Hygia multi, quite pricy but made for trikes and able to get with e-break and parking break. With a such heavy and powerful system i do not want to be a cheapskate on the brakes. Especialy when only having front brakes and no regen.


Rotors: Might be a little to much overkill with 2*203 floating rotors but with no real penalty in the terms of weight and price, so why not?
On the cheaper side for 203 floating but they have good user feedback, except being a little heavy.


CA: Picked up a V3 during the X-mas sale. Plan to use the tourqethrottle and temp limiting/monitoring. Will probably need to flash if with the latest firmware.

Battery compartment The plan is to print two "boxes" containing 6 (6 bricks fit comfortably inside printing volume) bricks each with the 3D printer i have access to (RapMan3). Shape and placement is yet to be decided.

Charger
Bought a used kingpan 1.2KW charger here on ES. Works but needs to be connected to an unused phase otherwise it trips the curuitbreaker.

 

[Mitch3514]

Awesome, looking forward to the pics! Good to see you have gone with the mini monster hub and have some solid electrical grounding- I will be watching closely as this is the motor I plan to use in my build also
Good luck!
Mitch

 

[Trackman417]

Nice build 8)
I hear you, I am an engineering major as well and as soon as the semester ended, I had the best sleep of my life lol.
I really like all the components you put together so far. But 40km/h on such a voltage I am not getting? I would add Zombiess throttle tamer so it would be easier to control the bike at low speeds. If you haven't ridden a high powered bike, the throttle is real twitchy.
Should be a beast when it's done though. :wink:

 

[Trilska]

One reason for the relatively high voltage is to keep the heat down and the revs up on the motor to gain higher effiency, and the top speed will end up around 55km/h. Also enables the use of a switched powersuply to power the 12v system for lights and main power relay (kilovac ev200). As for the twitchyness at high power, i plan to use the tourquecontrol of the ca and 3 speed switch.

 

[Tommy L]

I really like High voltage. I've gone up to 144v so far

I also have a Trike. Catrike 700 with a Bionx running at 36v. Watt hours per km are low at 40kph. 12 or 15wh per kph.

Post pictures as soon as possible! Nice to see other forum members projects!


Tommy L sends....

 

[Trilska]

Just a little update, components have been ordered (except motor and controller) and are starting to arrive, progress will be slow the next 30 days since i found a summer employment.

 

[xenodius]

I'll be watching this closely. I'm planning a KMX build as well, and I'm very interested to see efficiency figures from you using John's motor.

 

[Miles]

and I'm very interested to see efficiency figures from you using John's motor.

Me too

 

[Trilska]

Vacation have started and i have entered "Mullemeckmode" (Mulle Meck a Swedisch fictional character from children s books, tinkering with mostly old junk to build car, boats etc). So now it is time to start building!

To start with here are the main components.






View attachment 6

 

[Trilska]

Sorry for slow updating but i have been fare more busy this summer than expected, but not progress have accelerated and i suspect i have it up and running in time for fall.

Here are some pictures of the motor mounts and belt pulley.
View attachment 3

View attachment 2

 

[jansevr]

wow what a great selection of components and very nice machining as well! any more progress? im looking forward to seeing the completed product

gearing for a top speed of 55kmh is gonna give you a crazy acceleration especially with 24s - at 60a thats 6kw. are you planning on using the motor as a 2 speed? especially if you do i don't see why you couldn't reach closer to 80-90kmh and still have good acceleration.

 

[Trilska]

The plan is to keep the two speed switching to ensure decent efficiency at low speed and very heavy load (playing tractor?).
And sure i could gear it for higher speed but i don't really have the need/desire for it, partly for safety reasons and i still wish to be able to pedal it relatively effective.

 

[wojtek]

very excited to follow this build, good luck to you!

55kmh with this kind of power is nothing, i agree. High speed schlumpf is best way to go if you want to sync pedalling and motor work for up to 100kmh and even more.

I'm having smallest possible ring on mine and it is still too hard to pedal at 65kmh

 

[hydro-one]

That could work

 

[parajared]

Great to see another Typhoon build. I think they make superb little machines.

 

[Trilska]

I agree wojtek that a schlumpf HSD would be ideal, but at this point to expensive for me.

And if i feel that i have the need for higher speed i just have to make smaller rear pulley. But since this is my first e-bike i like to start a little slower.

 

[parajared]

I agree wojtek that a schlumpf HSD would be ideal, but at this point to expensive for me.

My Vuelta 60t on my KMX Typhoon isn't enough for me. My legs just end up paddling away worthlessly around the 28mph mark.

An alternative to Schlumpf that is about $600 cheaper would be to jackshaft your setup. You could use two "pillow blocks" to make a jackshaft, or use the hub motor itself as a jackshaft and run the power down your chainline.

 

[Trilska]

Progress is going slow, but now the motormods are almost finished. Here are some pictures as and uppdate.

The mods includes larger phase wires (going through an adapter and a bearing with larger inner diameter). The huge 20x47x14 bearings are not needed anymore when i am only supporting 5kg of rotor instead of the weight of a scooter in the original application.

A freewheel adapter what been modified and mated to the drive-side of the motor.


View attachment 4

 

[Trilska]

Slow progress, motorasembly almost complete so i will soon be able to mount the motor on the bike.

 

[Danny Mayes]

Wow, very tidy work there Trilska. Looks great.

Enjoying watching this thing shape up.

D

 

[Trilska]

Update:
Great progress now during the winter break. Motor mount is almost finished and pulley is fastened, i will hopefully be able to mount it on the bike soon. It is a quite tight fit so need to fix an issue with some rubbing.
Here are some pictures to further show the progress.







I think i am starting to get a little better with the cnc mill. Hopefully i will have the bike up and running until spring. I only need to mill the driven pulley and order a belt to finish the drive line.

 

[Danny Mayes]

This is one of my favourite builds. Great motor selection and implementation for a trike, and executed just stunningly. Gonna be a thrilling ride...

Enjoying watching it coming together from over here...

D

 

[Trilska]

Work continues, in writing moment the last pice of the drivetrain is in the mill.


I desided to redesign the driven pulley so it would match the contures of bicykle hub, to spread the tourque. So now it is quite a lot beefier and only aprox 40g heavier.

How i mounted the freewheel adapter to the sidecover. With 6 M8 stopscrews to lock it in place and take up the forces from the motor.


View attachment 3

Hopefully i will have the motor and pulleys and mounted on the bike at the end of the week. Then it is time to start working on the battery enclosure.

As a bonus here comes a happy stator in a Santahat :wink:


Ps. Will probebly remove the shifting mechanism due to the reason that it seems quite fragile and will probebly wont be able to keep up what i have in mind... Ds.

 

[Trilska]

Atlast the motor is in the bike, and everything seems to line up properly and it can rotate without rubbing.



And the pulley atached to the rear hub (quite a lot beefier than V1 who is pictured earlier in the thread and only 20g/half heavier)
View attachment 5

As for the motor in its mount it is quite tight between the motor and the mount itselfe. A standard pice of A4 office paper folded once would rub if placed in the minimal gap. I am not sure how i managed this, i know it would be tight but this is just ridiculous.
View attachment 4
But now you say "What about edy currents?". Since the backiron in this motor is quite thick there is hardy any fluxlel eakage and the tight spot is where the motor have a flange for the screwes to secure the sidecover so it have a little extra thickness there.

A closer look at the motor in its place underneath the seat.


Seems to line up properly, but i will need to implement an idler roller. Note the creative chainline, and yes it is on the agenda.


View attachment 3
Should maby shorten the screws a little.

 

[Danny Mayes]

Love it. Funny how the rear pulley is almost the same width as the rear tyre! Traction is going to be an issue