New Bafang Crank-Drives

[--freeride--]

I did a first testride yesterday and my wattsup sayed 37A max thats a lot more than the 25A the 750W Unit should have...
I am not sure if there is something wrong with the programming on my BBS02.
It is a blast to ride, but 37A seems to be to much. What do you think?

 

[Kepler]

If it is really 37A, it will kill the motor. Seems unlikely though. Do you trust the $20 Wattsup meter? Thinking how you can verify without installing another meter. What does it draw PAS only at the highest level? Mine draws around 500W (Calibrated CA)

On a 32 tooth, highest level and full throttle my bike just starts in break traction in gravel. This is at 25A, 26" wheel with knobby tire.

 

[Kepler]

Bafang came to the party with my one week old melted stator. They sent me the replacement stator
after couple of weeks of correspondence. Thanks to ES, especially Kepler for his effort in taking
the motor apart studying and explaining the failure with great photos. Also to AMY of GEB who
persisted with 8FUN relaying all my emails to Bafang with pictures and link to ES. They replaced
the complete sub-assembly of the stator, save us abit of work putting it back together.

We had a good look at the stator regarding rewinding it, I do not think is can be done my hand,
inbetween layers of protection PCB make it impossible to feel the copper by hand and pulling it
tight. Now we need to know if Bafang will sell the stator, l think some of us will need it with the
hard pushing.

Great stuff Avigo. So pleased they came to the party. See you tomorrow for a rebuild.

 

[--freeride--]

If it is really 37A, it will kill the motor. Seems unlikely though. Do you trust the $20 Wattsup meter? Thinking how you can verify without installing another meter.

Its a original Watts-Up not a 20$ one... Don't know if that makes any difference, but it allways was very exakt when I used it with my Hubmotors. It exaktly showed the peaks around 15A or 17A (got 15A and 17A controllers).

I am going to test tonight without throttle in level 9 and see what it says.
But 500W on 53V is only 9.4A...

 

[Samd]

Kepler I owe you a significant shout of beer on the next group ride - my BBS 350W still sits on the shelf as I complete my house (garage) move. This info is invaluable for planning. It's like watching one of those vicarious fishing shows when you can't get out there yourself. 8)
I've read back thru the thread and am wondering what voltage you are running against the 25A please?

I'm still toying with trying an external 6fet controller on the 350W, and upping the stock voltage / current a bit but am mindful of the slightly smaller physicals of the BBS01 vs the BBS02. Sounds like I may need to adjust the rear cluster accordingly as I found with my Aprilias.

 

[teslanv]

Just went for my first good test ride on my BBS-02 (750W) Bafang.
Used up 56WH in 2 miles. Included a decent hill.
The PAS is going to take some getting used to. I realized that you don't want to use it going down steep hills for the most part. Slight downgrades will still benefit from PAS. Going uphill in second or third gear at about 12 MPH with PAS set at 2 seems about as much as I need, with an occasional burst of the throttle. Anything more than 2 on the PAS and I might as well just use the throttle. And the jump between 1 & 2 is quite large. I'd like about 3 more PAS settings between 1 & 2.

I would like to do a little better on Watts per mile. At nearly 28 WMP, I'll have to charge at work to have enough to get back home.
lcrewse set me up with a max MPH of 30 (50 KPH) which is easy to get to on a slight downhill.

Overall I am impressed with the power. I pulled over 1200 Watts max going up the hill, which pegged my current at 25A.

Noise is not an issue at all. I hardly notice it.

Also, I see that lectriccycles is out 3 weeks on these now. (Not surprised at all.) I have a feeling these are going to be quite popular.

 

[--freeride--]

Checked my watts up yesterday and there is something wrong. It said 9.4A in level 1 and 25A in level 9. It felt like the 500W you mentioned... So i gess I need a new watts up...

 

[Kepler]

With the intention to fit the drive to a decent dual suspension platform, I know there is going to be no way I can stick with the 48 tooth ring gear that comes standard on the drive. So I spent the best part of the day fabricating an adapter to allow the fitment of a 104mm BCD chain ring while at the same time maintaining an acceptable chainline.

This is what I came up with.

The stock 48 tooth chainring still gives a tighter chain line due to it being large enough to overlap the gear case. However this setup is about as tight as you can get with 34 tooth to 44 tooth 104 BCD.

 

[footloose]

Nice work!
You didn't happen to make an extra, by any chance?

 

[Avigo]

Real neat work Kepler...we will see your Nordic Atomix soon...

I need help with the Bafang C950... l read the pdf file from Bafang...l do not think mine is the same version.

In setup l get the following..
1........ this l know rim size.
2........ option..10 - 35 kph ( what is this for????)
3........ option 1 - 3 ( what is it)

There is no menu for resetting DST. how do l do it.

Its pretty basic unit in comparision to later version, l missed it by 1 week.

 

[--freeride--]

Good work Kepler, here is my solution, lasercut by crossbreak:





The spider is stainless steel combined with 0.8mm aluminium spacers to be able to shim the chainring as tight as possible.

The origianl 46 with 2 spacers under it has the same chainline than the spider with rockring on the picture.



You need one spacer to clear the trani cover with the spider version.

So the over all offset from the stock chainring to the spider version is 3 spacers or 2.4mm.

 

[Kepler]

Very nice freeride. That is a better solution to mine. Did you design and draw it or did crossbreak? Nice to have the chain guard and adjustability.

 

[Kepler]

Real neat work Kepler...we will see your Nordic Atomix soon...

I need help with the Bafang C950... l read the pdf file from Bafang...l do not think mine is the same version.

In setup l get the following..
1........ this l know rim size.
2........ option..10 - 35 kph ( what is this for????)
3........ option 1 - 3 ( what is it)

There is no menu for resetting DST. how do l do it.

Its pretty basic unit in comparision to later version, l missed it by 1 week.

I have never read that manual but I presume 2... would be max speed. 3... backlight brightness.

On the C961, pressing the on and minus at the same time re sets the DST.

So how is the repaired drive going?

 

[--freeride--]

Very nice freeride. That is a better solution to mine. Did you design and draw it or did crossbreak? Nice to have the chain guard and adjustability.

I took the messurements and made a quick sketch, crossbreak did the drawing. You can use any Chaingard, the one on the picture is from the Bosch-system, very cheap, 25$ chainring and chaingard, available in 44T and 38T.
I will try a 42T on my bike that should give me 30miles topspeed and good climbing ability with a 42T in the rear.

 

[spinningmagnets]

What is the 5-hole BCD on the BBS02, and hole diameters? (in mm of course)

 

[aniken]

Real neat work Kepler...we will see your Nordic Atomix soon...

I need help with the Bafang C950... l read the pdf file from Bafang...l do not think mine is the same version.

In setup l get the following..
1........ this l know rim size.
2........ option..10 - 35 kph ( what is this for????)
3........ option 1 - 3 ( what is it)

There is no menu for resetting DST. how do l do it.

Its pretty basic unit in comparision to later version, l missed it by 1 week.

The previous reply is right only that (on my BBSO1 anyway) 2... is the speed limit on pedal assist only. Using the throttle over-rides this limiter making speed governed only by gearing, all other factors being ignored. On mine throttle crank speed on the highest power mode is circa 100 rpm under full throttle input based on my gearing calculations and the measured speed on the bafang speedo in a no load test.
The pdf from bafang/suppliers is often the one that states option 2 is the voltage setting menu. It states DST as 'single mileage reset' and the sequence explained does work on mine although I never use it. You need to be careful as the walk assist can be activated easily with random button holding.

EDIT...here is the manual I am on about...http://www.ebike-discount.com/onlin...RAL+MOTOR+DRIVE+SYSTEM+-BDS01-+Feb+182013.pdf

 

[aniken]

2 questions for those of you familiar with the bafang crank drive kits if I may...

1...Does anyone know where I can get the style of connectors that are used on the kit? Specifically for the throttle. I want to modify the throttle but cant seem to buy a bafang replacement part in the uk with the right plug on to cut up. I can get the same throttle unit for £15 easily but it has the wrong plug on it and I don't want to cut the loom on the kit. If I could find where to buy the plugs & sockets they use I would be laughing. I think they are specific to them, am I right?

2... If anyone else experiences random turning off of the C950 display unit then please shout out! Mine has some sort of endemic fault where after about 10 minutes or so of riding you stop say at a junction or crosswalk the speedo climbs down toward zero and as it hits zero the unit switches itself off! You have to then turn it on again, re-select your assist level (always high!) and off you go again. It never turns off while riding, its not a loose wire or anything, its in the software or display or something. I have taken to never stopping, instead maintaining a crawl whenever I can to keep it alive. On the odd occasion it wont do it, making me think there is a way around it. I have tried everything I can think off to diagnose it. At one point I thought that because I had spira-wrapped all the wiring together the brake cut off switches were causing interference with the display loom and sending the turn off signal to the controller but it wasn't that. My latest theory is that when on throttle the motor thinks its not running, and that only the pas gives it the 'on' signal so when you don't pedal for a while the controller goes into shutdown readiness awaiting the wheel to stop moving and turn off or something? Its weird but it doesn't really detract from me enjoying the unit as I just work around it, but I cant fix it either :? Little help?

 

[kocoman]

is the motor waterproof? if I use it in snow with slush will it short circuit? thx

 

[bose]

@kocoman: http://endless-sphere.com/forums/viewtopic.php?f=28&t=50104&start=825#p837603 two pages back..

 

[Avigo]

2 questions for those of you familiar with the bafang crank drive kits if I may...

1...Does anyone know where I can get the style of connectors that are used on the kit? Specifically for the throttle. I want to modify the throttle but cant seem to buy a bafang replacement part in the uk with the right plug on to cut up. I can get the same throttle unit for £15 easily but it has the wrong plug on it and I don't want to cut the loom on the kit. If I could find where to buy the plugs & sockets they use I would be laughing. I think they are specific to them, am I right?

You buy the loom set from Bmsbattery.com or greenbike, the socket is not colored..freight is the killer

 

[teslanv]

Got in a longer test ride tonight.
Conditions were a bit windy and some light sprinkles.

Ride from Lake Hills in Bellevue, WA to Mercer Island - About halfway up Gallagher Hill Road and then back home.

Distance totaled 13.5 miles
5.886AH on my 12S Pack - Ending Votage of 45.77V
270.9 Watt-hours
20.1 Watts per mile
25.3A Max Current
1202W Max Power

On Kamber Road (~2 mile hill @ 12% Grade) I consumed 50 WH. - Better than I thought I'd do.

I think I can make my Round-trip commute if I am judicious with the throttle and PAS settings.

I can't wait for the weather to improve.

Happy new e-cyclist now.

 

[Geebee]

Does anyone know how the crank drive would fit on a recumbent boom?
Would the motor hang down or against the derailleur mount?
The photo is just of the net but the boom and derailleur mount are the same as mine.

 

[Tom L]

Real neat work Kepler...we will see your Nordic Atomix soon...

I need help with the Bafang C950... l read the pdf file from Bafang...l do not think mine is the same version.

In setup l get the following..
1........ this l know rim size.
2........ option..10 - 35 kph ( what is this for????)
3........ option 1 - 3 ( what is it)

There is no menu for resetting DST. how do l do it.

Its pretty basic unit in comparision to later version, l missed it by 1 week.

Option 1 : wheel size
Option 2: Speed limit
Option 3: back-light brightness.

Press and hold (+) to toggle the backlight on/off.

Toggle trip / total odometer with the Power button when on.
Press and hold Power and (-) to clear the trip odometer when viewing it. You can't clear the total distance.

 

[Tom L]

2... If anyone else experiences random turning off of the C950 display unit then please shout out! Mine has some sort of endemic fault where after about 10 minutes or so of riding you stop say at a junction or crosswalk the speedo climbs down toward zero and as it hits zero the unit switches itself off! You have to then turn it on again, re-select your assist level (always high!) and off you go again. It never turns off while riding, its not a loose wire or anything, its in the software or display or something. I have taken to never stopping, instead maintaining a crawl whenever I can to keep it alive. On the odd occasion it wont do it, making me think there is a way around it. I have tried everything I can think off to diagnose it. At one point I thought that because I had spira-wrapped all the wiring together the brake cut off switches were causing interference with the display loom and sending the turn off signal to the controller but it wasn't that. My latest theory is that when on throttle the motor thinks its not running, and that only the pas gives it the 'on' signal so when you don't pedal for a while the controller goes into shutdown readiness awaiting the wheel to stop moving and turn off or something? Its weird but it doesn't really detract from me enjoying the unit as I just work around it, but I cant fix it either :? Little help?

The filth option in the advanced settings menu (after backlight level) is auto switch off time in minutes. Is yours set to zero? Set it to 5 or 10 minutes.

 

[Kepler]

Does anyone know how the crank drive would fit on a recumbent boom?
Would the motor hang down or against the derailleur mount?
The photo is just of the net but the boom and derailleur mount are the same as mine.

Ideally, it would swing up against derailleur mount. However, the clamp arrangement on the BB is very secure and you could probably get away with having the motor section at any position from low to high.