Bafang Ultra Fatbike build

[Daxxie]

How does the Ultra do bottom bracket size?. I realize no bottom bracket per se, but I want the big Q factor to go around a fat bike tire. Really just the chainring from center as far as possible.

There are 2 versions of the Ultra's spider. One specifically for Fatbikes.

[ErikYoung89]

This thread is a goldmine.

[JPLabs]

It sure is. Building with an Ultra drive isn't quite the daunting leap into the unknown, as it was before. The guys who dove in first, learned, and are now sharing what they learned, are e-biking heroes. Taking risks for the betterment of all.

Thanks guys!

[ErikYoung89]

Daxxie has considerable experience and I'm thrilled that he's sharing it in such a detailed way.

Hopefully whatever I learn from my steel frame mod I can share in an equally useful way.

[unclemike]

that's bitchen

[dev]

Hey Daxxie, cool build.

Can you post what was your final specification for the frame to the factory? It would greatly help as a starting point for ordering.

[Daxxie]

Frame specs:




Frame for Bafang Ultra G510

197x12 thru axle

26" 500mm 1.78cm

Headtube 41.8mm/52mm,

Head tube angle: 69°

31.6mm seatpost

seat tube angle: 73°




I’m 1.78cm tall and the 500mm frame is a little bit too big for me.

If I had to order one again I would go for 480mm




I also changed the water bottle holes so a Hailong big shark case would fit.

[andrie]

How do you like the Bafang Ultra and the Titanium frame? I'm thinking of doing a similar build.

[Daxxie]

I really love this bike.
Have 2 other BBSHD bikes but rarely use them anymore.

This titanium frames is very flexible. You have to get used to it initially.
The 2500w Ultra is very powerfull, I do have excessive drivetrain wear.
Still looking for better casettes and chains.

[AZguy]

SunRace makes very nice steel cog cassettes

[ChEBorow]

So, digging up this old thread. (Because project ChEBorow which will be documented in its own thread)

Daxxie: How did you get the speed sensor working? I have the same(ish) setup and need to move the speed sensor back or extend it to get it to read.

[weetard]

anyone else doing this build, i wanna start. never ordered anything from alibaba?

[Frankenbike]

Yeah I’m starting a similar build atm just not a fat bike was looking to do 54v internal battery but after reading this post thinking 72v as I have the space lol

[Daxxie]

So, digging up this old thread. (Because project ChEBorow which will be documented in its own thread)

Daxxie: How did you get the speed sensor working? I have the same(ish) setup and need to move the speed sensor back or extend it to get it to read.

Saw the pictures of your build. Nice!
Did you get the sensor to work?
Make sure the magnet passes near the body of the sensor, not near the mounting hole.

[Frankenbike]

Thanks daxxie thats a awesome bike and a great thread !!! Thanks again