AVIAN featherweight mid drive

[Ecyclist]

Couple of years back I visited Japan. That trip was mostly about something called 88 Temples Pilgrimage.
Most of people on that pilgrimage are Japanese and majority do the 1400km loop around the Island of Shikoku by foot.
I decided to do it by bike. It was not easy because Japan is mountainous. Double digit gradient roads are very common and some of them are inside of long tunnels. On that trip I met James, a dude from Australia, who suggested to look at the e-bike option.
After coming back to the U.S. I found ES forum, and, after months of educating myself, I decided to build my own e-bike so I can take it with me to Japan and other places in the world. This thread is about that build. I named my build AVIAN because I would like to be able to take this bike on the plane in its own case, my goal is to keep it under 55lb. including the case. My second goal is to have a very light, single track e-bike.
I made some progress that I would like to share with you.
The build is based on a 2009 Giant Trance X0, Alien RC motor and VESC controller. It is not finished, but is getting there.

 

[MadRhino]

Neat mounting. Looks good.
Small motor, how much power?

Battery is alway a problem when you plan to fly (double meaning) :wink:
What are your plans?

 

[Ecyclist]

Neat mounting. Looks good.
Small motor, how much power?

Battery is alway a problem when you plan to fly (double meaning) :wink:
What are your plans?

Thanks.
It is a 3200W motor but I'm not going to push it over 2400W. BTW I can install up to 8072 6000W motor to that reducer and pull that bike apart. Just don't feel like doing it yet. 500/14 Rohloff might not like it either.
I already designed solder/spot welder free case and am planning on buying 18650 cells at destination or ship cells by sea and pop them in.

 

[12-C]

Beautiful build!

Really nice work with the battery setup!

I'm guessing you have access to a mill ?

 

[Ecyclist]

Beautiful build!

Really nice work with the battery setup!

I'm guessing you have access to a mill ?

And then some.

 

[flathill]

Cool battery pack!

Are the holders/connectors made of aluminum? If so what about oxidation? Aluminum oxide is a insulator. I guess you could sand before assembly and hope it stays air tight...

Maybe you know this and they are nickel plated copper?

 

[Wolfeman]

Wow, just freakin wow.....

 

[ScooterMan101]

Great Work,

I have had the same Idea for about a year or so now, I just do not have the Machine Shop to do this myself.
( I Bought a Frame a year ago but just got around to building it up, since I finally see some improvements in regards to DIY Mid-Drives )

I have been wondering how to use a RC motor with a Infineon or Infineon Clone Controller, so as to use a Cycle Analyst to do easy Voltage and Amperage Limit's .

Would that motor work with an Infineon controller ?

What is the KV of the Motor ?

Are you going to be operating it with 5s pack or 10s pack, ... or is that a 6s x 10p Pack ?

 

[Rube]

Wow, amazing work. Your battery construction deserves its own thread. Interested to see how you mount the pack. Any lessons or thoughts about your battery design? Would you change a future iteration? cheers

 

[Ecyclist]

Cool battery pack!

Are the holders/connectors made of aluminum? If so what about oxidation? Aluminum oxide is a insulator. I guess you could sand before assembly and hope it stays air tight...

Maybe you know this and they are nickel plated copper?

Thanks!
Yeah, these are aluminum and earmarked for electroless nickel plating.

 

[Ecyclist]

Wow, just freakin wow.....

Thanks dude. You made my day.

 

[Ecyclist]

Great Work,

I have had the same Idea for about a year or so now, I just do not have the Machine Shop to do this myself.
( I Bought a Frame a year ago but just got around to building it up, since I finally see some improvements in regards to DIY Mid-Drives )

I have been wondering how to use a RC motor with a Infineon or Infineon Clone Controller, so as to use a Cycle Analyst to do easy Voltage and Amperage Limit's .

Would that motor work with an Infineon controller ?

What is the KV of the Motor ?

Are you going to be operating it with 5s pack or 10s pack, ... or is that a 6s x 10p Pack ?

I recommend VESC or RC controller for a RC motor.
The motor is 125Kv.

 

[Ecyclist]

Wow, amazing work. Your battery construction deserves its own thread. Interested to see how you mount the pack. Any lessons or thoughts about your battery design? Would you change a future iteration? cheers

Thank you.
You need to be really careful with these cells. Steady hands or welding goggles are at premium. 8)
This is my third rev. and I think that for 6P it will work OK.
After I install it on the bike and put it through real life situations I will be able to tell more.
For now I only used it for testing the motor with my transmission on a fluid exercycle.
I will build more compact 4P for single tracking and short range.

 

[cal3thousand]

Umm... I'm really glad that I clicked your link. Wasn't sure what to think based on the name and TOTALLY did not expect to see that battery setup.

I would absolutely love to hear anything you would care to share about the construction, design and manufacture of that beauty.

Seems like you may have also designed your own motor mounting as I have never seen one of those on offer before.

Subscribed in the hopes of learning more about your creations!

 

[Ecyclist]

Umm... I'm really glad that I clicked your link. Wasn't sure what to think based on the name and TOTALLY did not expect to see that battery setup.

I would absolutely love to hear anything you would care to share about the construction, design and manufacture of that beauty.

Seems like you may have also designed your own motor mounting as I have never seen one of those on offer before.

Subscribed in the hopes of learning more about your creations!

I'm glad you did.
It would be very hard for me to write about everything I build. I doesn't look like much, but just the transmission was a big project in itself. So if you have a specific question, just shoot it my way and I will do my best to answer.
You are correct about the motor mount. Giant bikes have goofy rear shock linkage so I had to come up with something that works. That was the price I was willing to pay in order to have ample space in a triangle of the bike. I can fit everything in that space. These brackets are very short. Short mount makes for a very rigid structure.

 

[ScooterMan101]

Is that regular bicycle chainring on the outside of the crank that has the chain to the motor ?

Regular bicycle sprocket on the motor ?

8 or 9 speed chain/chainrings and sprocket up front ?

 

[Ecyclist]

Is that regular bicycle chainring on the outside of the crank that has the chain to the motor ?

Regular bicycle sprocket on the motor ?

8 or 9 speed chain/chainrings and sprocket up front ?

No, these are BMX 7075 aluminum chainrings. Both are 104 BC. The outside is 42T and inside 44T. The transmission is running 20T right-hand EXCESS freewheel with backing plate.

 

[sephespid]

Wow, amazing. subscribed
It looks like bobc's lazer cut cycloidal gearbox. I need this type of gearbox. Compact and simple.
But I think there is a problem of protecting the motor from water or mud.

 

[anttipaa]

Wow this looks very good. Are you going to sell those gearboxes? How much does that gearbox weight?

 

[Rouckie]

I'm also very interested in the gearbox. Could you show some more details of the internals? Is it something I could duplicate (I also have a cnc).

thank you

 

[SlowCo]

Subscribing to see if you'll share more on the internals of the gearbox as well. Great little machine!

 

[Ecyclist]

I designed and built the hypocycloidal transmission based on three different Sumitomo transmissions that I bought and studied. Sumitomo makes industrial type of transmissions, which are not restricted in size and shape. I had to rethink the whole thing for the bike use.

@SlowCo Next week I will have some free time and I will take the transmission off the bike, weigh it and take a couple of photos.
Below, I posted a photo of the first revision of my transmission. The one on the bike is rev.3.

@Rouckie You will need CADCAM and second software to design cycloidal shape. From what I understand, you can use Solidworks for everything but it is very expensive.

@sephespid If you cut cycloidal shape with laser, you will get a rattle box. Sumitomo uses profile grinders to get a perfect shape. CNC milling is barely acceptable. I'm not worried about the motor too much. E-sk8s have these motors mounted couple of inches off the ground and can live with that. Worst case scenario, I will swap it with Astro Fight inrunner. No problem.

@anttipaa At this point my focus is on building mid power super light e-bike for myself, but I might make a short run of 10 to 20 units once I get positive singnals from the community. The time will tell.

 

[Amiran]

Crazy stuff.
Great thread.

 

[Mongo1]

Brilliant work!!!

 

[neptronix]

That is cool as hell. Too bad it's a one-off.