New Bafang Crank-Drives

[teslanv]

Alan,

I have a BBS02-750 Kit, and I can reliable get 10 Watt-hours per mile riding at 16 MPH, with 40% assist (About Level 4 of 9)
You can ignore the 750W rating of that motor, however. It's just a sticker. The reality is that you will use whatever wattage you use, and with 25A & up to 54V (13S LiIon) you could at times be pushing 1350 watts to the motor. However, if you are using a 40% assist, you will generally only be using around 200W-400W at any given moment.

A better gauge would be to base the battery size on total watt-hours at your estimated economy. To be conservative, use 15 Whs/mile. - so if you want to go 30 miles, you will need 30x15 = 450 Watt-hours or a 48V-9.38 Ah battery - So you should get either the 29E cell Frame pack (13Sx4P) or wait until Paul has the 25R Cells in, which should also be close to 10 Ah but better able to take the max. 25A Current. - You can also de-rate the 750W kit, so it will never draw more than 18Amps (or whatever amount of current you like) by requesting from Paul, or programming yourself with a cable, in which case, the 29E cells should be fine.

 

[0utrider]

... A better gauge would be to base the battery size on total watt-hours at your estimated economy. To be conservative, use 15 Whs/mile. - so if you want to go 30 miles, you will need 30x15 = 450 Watt-hours or a 48V-9.38 Ah battery

Great info!

 

[tomjasz]

Finally, does anyone recommend dropping power to the BBS01 350W - would be very kind to the battery and probably give better range at expense of speed. Of course the motor is liable to be pushed harder - is this a problem?

Alan

My upright crank forward KHS Smoothis carries my 220lbs/100kilos at 19-21 MPH with a 13.8AH battery from EM3ev. I get just over 25 mies with full assist and throttle. I'm dialed and use it on flat ground. It will climb up onto dikes roads like a champ. but that is not typical use. My wife at 120lbs runs a consistent 22MPH on the same rig.

 

[teslanv]

Yep. Just keep in mind 15 Watt-hours per mile is based on a fairly light level of PAS. If you are riding WOT, 30 MPH, and not pedaling, your economy can get as bad as 40+ Watt-hours per mile.

Economy approaches 0 Watt-hours per mile, as the rider does most of the work, at which point, you are just hauling around 20 extra lbs of motor and battery. - In my experience, a 40%-60% PAS level makes for a comfortable, and decently speedy ride.

 

[tomjasz]

40%-60% PAS level makes for a comfortable, and decently speedy ride.

What king of speeds are reached at 60%? Full throttle?
Curious, hopefully I won't feel to bad. Actually 20MPH for a gimp is quick enough. I'm wondering as a pal is thinking about building a setup with my tools and a bit more experience...

Tom

 

[teslanv]

60% PAS - I get around 22-24 MPH
WOT, 28-32 MPH, depending on slight grade & headwind.

 

[Kepler]

Here are some numbers from my ride to work this morning.

I need to keep the assist up at around 400W to average this speed. I spent most of my time at around 40kph on this trip however your average gets quickly dragged down slowing down and taking off after traffic lights.

 

[arclarke]

Alan,

You can also de-rate the 750W kit, so it will never draw more than 18Amps (or whatever amount of current you like) by requesting from Paul, or programming yourself with a cable, in which case, the 29E cells should be fine.

Thanks for that - I guess a 750W derated to 18A is basically the 500W 48V motor.

Still wondering if this would differ in use from the 500W 36V.

 

[arclarke]

40%-60% PAS level makes for a comfortable, and decently speedy ride.

What king of speeds are reached at 60%? Full throttle?
Curious, hopefully I won't feel to bad. Actually 20MPH for a gimp is quick enough. I'm wondering as a pal is thinking about building a setup with my tools and a bit more experience...

Tom

Tom
So my question is would you still buy the 350W, or are you feeling left behind now?

Alan

 

[arclarke]

Here are some numbers from my ride to work this morning.

I need to keep the assist up at around 400W to average this speed. I spent most of my time at around 40kph on this trip however your average gets quickly dragged down slowing down and taking off after traffic lights.

Nice lot of data there. Looks like you're drawing average 225W and getting avg speed 32km/h, overall 7Wh/km - promising.

 

[pjgold]

For an easy life I like the look of the ready made frame pack which locks onto the bottle cage mounts, but it isn't the biggest pack and I will want to maximise the range - aiming for at least 30miles at 20-22ish mph (with a fairly upright riding position), though I pedal well enough to average 14-15mph without a motor.

For range the high charge samsung 29E type cells look best.
The 750W sounds nice but drawing 25A needs 6 cells in parallel but the rigid pack only fits 13S4P so no good - I want to avoid easily removed battery frame bags. And do I really need 750W?

500W at 48V draws 18A so will just about work with the 4P pack

Alan

Hi Alan
I have the BBS02 750w with a Frame pack of 29E's.
I picked the frame pack for the ease of install the same as you are thinking and I commute 46km everyday and have been doing so for just over 4000km now.
I run my 750w at 18w to spare the battery, that said I rarely use more that 50% power anyway and have it set at around 25%-30% for most of my commute. In fact my level 9 is set to 70% and I have nice fine 5% increment power levels up to 40%
I don't have a watt meter installed but I believe I am using around 8-10Wh/km based on the battery size and what charge is left each day.

Definitely go with either the 48v 750w or 500w unit, it easy to turn it down or tune the software to suit.

cheers

 

[mclark999]

I'm finally getting round to ordering a BBS02 mid drive and battery, and realised there's a few options to juggle in terms of volts and battery.

For an easy life I like the look of the ready made frame pack which locks onto the bottle cage mounts, but it isn't the biggest pack and I will want to maximise the range - aiming for at least 30miles at 20-22ish mph (with a fairly upright riding position), though I pedal well enough to average 14-15mph without a motor.

For range the high charge samsung 29E type cells look best.
The 750W sounds nice but drawing 25A needs 6 cells in parallel but the rigid pack only fits 13S4P so no good - I want to avoid easily removed battery frame bags. And do I really need 750W?

500W at 48V draws 18A so will just about work with the 4P pack,
but there's also a 500W at 36V - this draws 25A again, but at 36V the battery pack holds 6P so can do 25A OK.
And 10S6P is a 15% increase in capacity over 13S4P which would help with range.

Any other differences to worry about between the 36V and 48V versions of the 500W?

Finally, does anyone recommend dropping power to the BBS01 350W - would be very kind to the battery and probably give better range at expense of speed. Of course the motor is liable to be pushed harder - is this a problem?

Alan

You can get 30 miles at 21-22 mph out of the 750 watt 48 volt 10ah battery if you are willing to pedal vigorously about half the time. You can get quite a bit more mileage if you drop down to 18-19 miles per hour. I have a fairly upright package and those extra mph add a lot of wind resistance. I typically am running 500 watts per more and pedaling briskly to achieve 21 mph

 

[astmacca]

Much happiness.

I have permission from She Who Must Be Obeyed to order my kit this Friday. Going to order from EM3ev and get the 48V / 500W with 29E celled 11AH battery.

Seems to me that's the best combination for balance and keeping the weight low. Going to bung it on my old Apollo MTB that i use mainly for commuting and light recreational riding on the weekends. Will also order a pair of Hidden Wire Brake Sensors since my shifters are integrated with the brake handles, and i have visions of uprgrading the bike in a year or two to something with hydraulic disks.

I have an idea for using those HWBS with hydraulics which i will try out if it becomes relevant. Basically run a short cable into the HWBS with a light spring in there it ensure smooth return after letting the brakes off, and hang the HWBS off the hydraulic line near the brake handles. I think it could be a pretty neat setup but will probably go through a few iterations ( if i ever get a bike with hydraulic disks? ) making it work.

From all my reading in many places looks like a de-rated 48V 750W kit (with the 25A controller programmed for 18A ) is a durable solution. I am also going to ask if it can be delivered with the stock 46T rather than 48T chain-ring as top speed is not my concern. Hill climbing, easing the load into headwinds, and durability is.

The std programming that Paul does looks pretty suitable for me. 100% throttle available in all PAS modes. PAS level 1 starting @ 20% (100W output??) and going up in 10% increments to 100% @ PAS level 9. Frankly i will probably set the speed limit down to about 25 / 30km/hr. I currently ride for fitness (but have dicky knees ) so don't mind pedaling. And since i am in Oz which has silly rules :x like a 6km/h limit on throttle i have to be discrete.

One option that i am considering as a future project is fitting a Cycle Analyst V3. Largely to get access to the different mode settings. I'd have a "normal" for my commute, "full on" for the occasional off road, and a "legal" for sedate cycle way jaunts with the family.

Is Cycle Analyst a simple plug in install for these kits or do they need to be spliced in to the wiring somehow? And, do they replace or supplement the supplied display??

Anyhow, that's the plan. If anyone more familiar with this kit see's any glaring, "OMG don't do that!!!" issues with it would appreciate hearing their opinions so i can consider.

And thanks everyone who contributes here. Very useful thread.

 

[dumbass]

astmacca, I have the 48v 500w kit on my old EZip steel frame and it has run great but I've only got about 160 miles on it. I am guessing it is tuned down a bit as well because the max I've ever seen it draw is about 825w to 850 (about 16.5a) and that's with a 48v 20ah pack. I've checked it many times after a speed run ( max speed seems to be about 26.2mph with no peddling) and after a good hill climb. The motor/controller hardly seem to get warm. You can certainly hold your hand on it. BTW, mine came stock with the 46t ring whereas, my 750w model came stock with a 48t ring. I'm guessing this is likely the way they package them from the factory. But I would note it with Paul just in case.

Bob

 

[Kepler]

Good choice of drive battery combo. Should be around 100W at the lowest assist level.

In regards to CA3 integration, check this thread out for more info http://endless-sphere.com/forums/viewtopic.php?f=28&t=60433&start=0

I am currently using a CA2 with a custom remote shunt together with the standard display. I also have spliced into the stock wheel speed sensor for the CA2 speed signal. Looks a bit over the top with the 2 displays but it is so nice having all the information of what's going on electrically with the bike.

 

[astmacca]

The motor/controller hardly seem to get warm. You can certainly hold your hand on it.

Excellent! That's really the result i am aiming for.

kepler, thanks for the link to the CA3 thread. Having read through it, I suspect i will stay stock for a while and see how things go. Will be a while before i am comfortable with the idea of hacking around the wiring to that extent.

Thanks.

 

[dumbass]

The motor/controller hardly seem to get warm. You can certainly hold your hand on it.

Excellent! That's really the result i am aiming for.

kepler, thanks for the link to the CA3 thread. Having read through it, I suspect i will stay stock for a while and see how things go. Will be a while before i am comfortable with the idea of hacking around the wiring to that extent.

Thanks.

But as you are ordering from Paul you should have him add the extension cable that other posters have indicated he now offers. Buying the cable from him now is (I think) under $10. Whereas, buying it later will not only cost more because of the shipping but cause you more delay should you need it.

Bob

 

[speedmd]

Buy a bunch, I need one also. Will pay you a fair markup for one.

 

[tomjasz]

Buy a bunch, I need one also. Will pay you a fair markup for one.

Another group buy? I'll see if he'll sell a dozen.
He suggested they would be priced at $6.00. A dozen shipped with PapPal and exchange fees fees would be $100. The last bunch I reshipped in small flat rate boxes for $5.75. $15 reshipped to any USA address. Canadian first class postage was around $7.00. I would mind having a spare or two.

Takers? Remember you still need an adapter for $4-$10 to build the Pexio design.

viewtopic.php?f=28&t=58780&p=915832&hilit=pexio#p915172

Last time everyone PP in advance and it took a couple of weeks. That round was $30. Several of us have piggy backed small items and reshipped for each other. Great way to get a deal among known and trusted members.

http://endless-sphere.com/forums/viewtopic.php?f=31&t=61410&hilit=pexio+cable

 

[tomjasz]

40%-60% PAS level makes for a comfortable, and decently speedy ride.

What king of speeds are reached at 60%? Full throttle?
Curious, hopefully I won't feel to bad. Actually 20MPH for a gimp is quick enough. I'm wondering as a pal is thinking about building a setup with my tools and a bit more experience...

Tom

Tom
<SNIP>Are you feeling left behind now?

Alan

Alan,

If I were a younger more aggressive rider and had built up a MTB I would. Or if there were a delta trike that would take a 750W I also would. But for what I have. Two, crank forward, errand and bike trail bikes, run on level ground I would do the 350 again. I think another advantage to the 48V are the number of users posting perhaps there's more support here.Especially when configuring batteries. That said, I find 18-20 faster than what traffic expects out of me as it is. I frankly wouldn't feel safe at 25-30. I have improved the braking by upgrading the pads, That gave me more confidence. BTW I came to these after nearly a decade on a Vespa GTS. I did like speed but with much more capable braking and engineering for the speed. Personally I'd prefer the robustness of a moped over a bike at speeds over 25.My perspective comes from an aging gimp who's life has been changed by E Bikes. The BBS01 and 36V battery fits my budget a little better too.

 

[0utrider]

Takers? Remember you still need an adapter for $4-$10 to build the Pexio design.

Roger that. Add one to the list.

 

[arclarke]

Alan,

If I were a younger more aggressive rider and had built up a MTB I would. Or if there were a delta trike that would take a 750W I also would. But for what I have. Two, crank forward, errand and bike trail bikes, run on level ground I would do the 350 again. I think another advantage to the 48V are the number of users posting perhaps there's more support here.Especially when configuring batteries. That said, I find 18-20 faster than what traffic expects out of me as it is. I frankly wouldn't feel safe at 25-30. I have improved the braking by upgrading the pads, That gave me more confidence. BTW I came to these after nearly a decade on a Vespa GTS. I did like speed but with much more capable braking and engineering for the speed. Personally I'd prefer the robustness of a moped over a bike at speeds over 25.My perspective comes from an aging gimp who's life has been changed by E Bikes. The BBS01 and 36V battery fits my budget a little better too.

Tom
thanks for that, feels reassuring - after all adding a 350W motor is probably a 200% increase in power over just pedalling, which might be enough for an ordinary rigid fork bike. As I see it the battery side works out better at 36V since you get more cells in parallel and can cope with higher current more easily from a standard pack.

Alan

 

[astmacca]

Sorry speedmd, i am other side of the planet from you so is suspect no advantage in ordering you a cable.

However if anyone local is willing to take a punt and wants something small added to my order, PM me to discuss. New to this so on an all care but no responsibility basis.

I am going to be away on holidays (sunny Coral Bay ) for a week around the time i think my order may get here. So.....i am using the store at my work as my mailing address since the girls there deal with couriers all the time anyway and are happy to help out and keep it for me till i get back.

 

[Lenk42602]

you can not tell folks that short cage will work with a 36 tooth.

Here's the video of my bike's drivetrain.

11-36 cassette 9 speed cassette, 105 9 speed short cage derailleur. nothing janky about it and it shifts like it was meant to.
[youtube]bFl3Io-dHZk[/youtube]


len

 

[Lenk42602]

Here are some numbers from my ride to work this morning.

These are extremely close to the numbers I generated on my commute as well.

Len