BBS02B/750w: First Build

[AHicks]

This blog is possibly the best resource for programming.

A Hacker’s Guide To Programming The BBS02 & BBSHD

One way that the BBS02 middrive unit shines over other competition like the Bosch is the ability to program the controller yourself. Although the process of programming the controller will void any…

electricbike-blog.com

I've read that about 6 times now, and I believe it's starting to soak in. The first couple of times I tried to skim through it quickly, and felt like I was reading a language I didn't understand.

I noted on a ride today for instance, that the bike I've been riding with a stand alone KT controller, responds much differently between PAS level changes and throttle input. PAS level changes are subtle, while throttle is more of a right now response. Feeling now is I know just enough to be dangerous!

 

[AHicks]

I tried to upload a bunch of .el (program parameter files) but couldn't. I still run EM3ev files and while I support users making changes to suit, I find the base programming just fine. But remember, I've regressed and now am happy with 20MPH speeds. Been riding my 2014 BBS01 350W daily. Full dork!

Thomas, I rarely ride even 20mph. Not about high speed performance here either. I'm looking at the big motors for reserve power more than anything else. Need it occasionally for hill climbing performance. This 300 lb butt and little motors don't get along well.

I'm spoiled with the ultra smooth response I've been getting from the KT cadence sensing the last few years (I'm on my 3rd bike using KT controllers purchased on the aftermarket). I'm way more concerned about cadence sensing performance in the 5-15mph range than anything else (not into jerky motor stopping and starting to maintain a speed I want to ride at) . After reading that article a few more times, feeling that eventually I'll be a little more comfortable about doing some tuning to fit my purposes.

Gionnirocket, thanks for your patience. Apologies for taking your thread so far off topic. I may start a thread dedicated to the info I'm after soon, here in the Bafang forum.

Many thanks for those sharing info. Much appreciated! -Al

 

[Gionnirocket]

No worries Al.

I too am not about speed and actually enjoy it more when it's under my power and not the motors.
I have it now where the motor cuts in and out and I hardly feel it and sometimes don't even realize unless I glance at the display.
I've been planning on starting a new thread for programming for us older gents as most of the stuff out there is for aggressive performance driven whipper_snappers. Just waiting for a rainy day to take some screen shots.

 

[AHicks]

I peddle from the time I leave until I get back. For me it's about matching what I feel like putting in to it with the motor's power to arrive at a speed I feel like traveling at the moment, to match current conditions. Hills, surface (grass, gravel, hard packed single track, pavement that's in good shape, pavement that's turning back in to gravel, etc) and other conditions that are ALWAYS changing! That's what keeps it interesting for me.

I'll save up some questions and join you if you've started something, or start one of my own. In any case, to be continued. Maybe we can get something interesting cooking. -Al

 

[tomjasz]

The 350w is probably a little tamer to start... The 750w is too jumpy with the base programming for my full dork rides.

Too jumpy is definitely a function of programming. Typically customers want the fastest settings possible rather than tame rides.

 

[Gionnirocket]

Too jumpy is definitely a function of programming. Typically customers want the fastest settings possible rather than tame rides.

I concur
And that's why all the programing info available points in that direction.

 

[Gionnirocket]

Finally got around to checking the grease at around the 1650 mile mark. I wasn't hearing any noise but I opened her up, blew and wiped out as much of the Bafang grease as easily possible and repacked it with the Mobile SHC 100.
The amount of grease that was used at the factory seemed adequate, but I went a little heavier, but not near the amount the video suggested.
Went for a quick ride and all seemed the same.

I forgot to mention when I originally posted this that I think it's a good idea to check this periodically as when I did I found a small amount of debris starting to make its way past the cover and into the gear area. Mostly road dust but it can't be a good thing.

 

[Lar]

Interesting read... I'm considering doing a bbs02b conversion due to there availability and lack of factory builds. Thought if I do I'd go with bafang usa direct my problem may be the battery fit though. I think I can squeeze in the ultra thin shark battery they offer but due the the water bottle bolt location it would have to mount upside down which seems like the wiring might not be long enough. I don't really want to tap any holes in the frame if I don't have to but the other thing it's only a 11 ah battery so I don't know if that's quite enough for what I was wanting. 140nm sounds like plenty of power.

 

[Gionnirocket]

Interesting read... I'm considering doing a bbs02b conversion due to there availability and lack of factory builds. Thought if I do I'd go with bafang usa direct my problem may be the battery fit though. I think I can squeeze in the ultra thin shark battery they offer but due the the water bottle bolt location it would have to mount upside down which seems like the wiring might not be long enough. I don't really want to tap any holes in the frame if I don't have to but the other thing it's only a 11 ah battery so I don't know if that's quite enough for what I was wanting. 140nm sounds like plenty of power.

In my case I went with a 17.5ah battery as I feel larger batteries are more stable and provide capacity for unplanned adventure. I have more than enough capacity for my style of riding as I'm mostly looking to exercise with motor assist to increase the amount of time I'm able to stay out there. I've reduced motor output to make the motor engagement smoother and less intrusive so in my case the motor has more than enough push. All configured the bike is about 65lbs and I'm an additional 160lbs.
Battery fit was and still continues to be in a minor issue. With full suspension I could not fit any water bottle or triangle frame mount batteries and my options were a custom build or rear rack mount for which I went with the latter. With near 2000 miles on the setup I've been very happy with the results so far.
One note on Bafang USA Direct... I have no experience with them but I do believe that they have no affiliation with Bafang in China. It's just a name chosen for marketing purposes.

 

[Lar]

^^^ My thought too on extended rides having the higher AH but not wild about the full suspension racks I've seen but may be the best option. Realistically all I need is around 25 mile range but with extended climbs that number doesn't apply even with PAS I suppose. Bafang direct is suggesting the 52 v for that.. read somewhere that was hard on the motor but assume they know better. I had heard they were not affiliated with Bafang and I kinda like that. The other thing that impressed me was they have printable templates for the batteries so takes the guess work out. Don't think they are cheaper than amazon but my thinking is their technical support would be worth having.

 

[Lar]

Bafang usa got back with my question about the battery. They sent me a pretty good link for checking your bike compatibly (good thing) and the chainstay might be an obstruction on my bike. Need some more specific info as to the dimensions though which I've asked for. Anyway here's the link for anyone contemplating doing a conversion.

https://support.bafangusadirect.com/en/articles/2965363-will-the-bafang-mid-drive-motors-fit-on-your-bike

 

[tomjasz]

Need some more specific info as to the dimensions though

I find the best way to sort a kit is to do two searches.
1. BIKE BRAND, Bike model, and BBSHD and again with BBS02(if your bike is 68-73mm bottom bracket.)

For example, KHS smoothie BBSHD

 

[Lar]

I find the best way to sort a kit is to do two searches.
1. BIKE BRAND, Bike model, and BBSHD and again with BBS02(if your bike is 68-73mm bottom bracket.)

For example, KHS smoothie BBSHD

The bike isn't that common so no luck there but I did come across this and sounds pretty convincing that it won't fit.

 

[tomjasz]

The bike isn't that common

What brand and model? How wide is the bottom bracket? Some with 100mm bottom brackets used 120mm kits and were able to clear but that's a mediocre solution with other pitfalls.

 

[Lar]

It's a Marin Hawk hill.
They just sent this:
The important dimensions to note are:

1) Your bikes current bottom bracket width.
2) If the motor would hit your bikes chainstay
3) If the sprocket would hit your bikes chainstay

If either 2 or 3 happen you will need to either use spacers (if there is enough shaft room left of the motor through your bottom bracket. Or if not you will have to upsize to the next size motor (ie. from 73mm to 100mm) in order to make the motor work with your bike and clear any chainstay obstructions. However note that increasing the size of the motor and adding spacers for clearance can cause alignment issues.

 

[Lar]

I assume the alignment issue he's referring to is with the chain if I went to a bigger bracket one.

I have a 73 mm.

Going off the dimensions the BBS02 wouldn't fit as far as I can see though.

 

[tomjasz]

I assume the alignment issue he's referring to is with the chain if I went to a bigger bracket one.

I have a 73 mm.

Going off the dimensions the BBS02 wouldn't fit as far as I can see though.

There is no 100mm or 120mm BBS02B. And yes it's all about chain line!

 

[Gionnirocket]

I used these diagrams to fit it to my bicycle.

Using the center line of your bottom bracket and measurement F along with the diameter of your chosen chainring you should be able to figure out if it will work. A smaller chainring will allow greater clearance to the chain_stay

 

[tomjasz]

If either 2 or 3 happen you will need to either use spacers

It looks like you have 2.3" tires. I can't imagine the fit being a problem. Is it a standard square taper bottom bracket??
Battery placement will be the biggest issue.

 

[Lar]

There is no 100mm or 120mm BBS02B. And yes it's all about chain line!

I know.... would have to the next size motor.