New Bafang Crank-Drives

[Zippy Hawaiian]

Hope to build in 6 weeks or so...
No shocks, just cushy fat frank balloon tires and a sprung saddle.
Feel free to comment


Frame_________Soma Juice 2013 15.5" chromoly (nickel color)
Electric Motor___Bafang bbs02 750W
Battery________Samsung 29e, 50V 14AH em3ev
Transmission____Nuvinci 360, 22t cog
Fork__________ Salsa Cromoto Grande rigid, VO headset
Hub___________Paul Disk FHUB
Brakes_________BB7 road 160mm x2 + shimano cable
_______________Soma reverse brake levers (hidden wire brake sensors)
Handlebars_____ Nitto Albatross chromoly
_______________Soma Stem 110mm
_______________Miesha's cork grips
Saddle_________VO model 8 & VO seatpost
Pedals_________ VO Sabot
Wheel_________Fat Frank 29x2" (cream)
______________SV19 tube + slime
______________Velocity Blunt rims 700c/28mm, DT comp spokes
Chain__________KMC X8.99

Dunno how I'll mount the battery but I can't stand the look of triangle packs.
Found suitable fenders but haven't decided whether to use them on this bike.

 

[Rusty123]

Guys, I think I may have found my new bike to bafangnize .

If I were looking to buy a new bike to convert to electric, I'd lean towards just buying an electric bike, probably with the Bosch drive unit. Like these:

http://www.electricbike.com/bosch-cannondale/
http://www.feltbicycles.com/International/2014/Bikes/ebike/QXe-Men/QXe-85-EQ.aspx
http://www.haibike.de/produkte_detail_en,3009,20501,detail.html
http://www.bosch-ebike.de/en/produkte_neu/marken_2/alle_marken_1/alle_marken_1.html

Which one is available to buy in the USA?

Good question. I've not shopped for them - can you not purchase eBikes in the states?

 

[Rusty123]

Hope to build in 6 weeks or so...
No shocks, just cushy fat frank balloon tires and a sprung saddle.
Feel free to comment


Frame_________Soma Juice 2013 15.5" chromoly (nickel color)
Electric Motor___Bafang bbs02 750W
Battery________Samsung 29e, 50V 14AH em3ev
Transmission____Nuvinci 360, 22t cog
Fork__________ Salsa Cromoto Grande rigid, VO headset
Hub___________Paul Disk FHUB
Brakes_________BB7 road 160mm x2 + shimano cable
_______________Soma reverse brake levers (hidden wire brake sensors)
Handlebars_____ Nitto Albatross chromoly
_______________Soma Stem 110mm
_______________Miesha's cork grips
Saddle_________VO model 8 & VO seatpost
Pedals_________ VO Sabot
Wheel_________Fat Frank 29x2" (cream)
______________SV19 tube + slime
______________Velocity Blunt rims 700c/28mm, DT comp spokes
Chain__________KMC X8.99

Dunno how I'll mount the battery but I can't stand the look of triangle packs.
Found suitable fenders but haven't decided whether to use them on this bike.

I had an albatross bar - sweeps were too long to accommodate the BBS01 brake cables. Swapped out with a Surly Openbar, which worked fine.

 

[Zippy Hawaiian]

Thanks but am not using the kit brake cables, using HWBS (hidden wire brake sensors) instead.
That way I can use reverse brake levers.
They fit into the bar end of handlebars like this:

 

[nukezero]

Thanks but am not using the kit brake cables, using HWBS (hidden wire brake sensors) instead.
That way I can use reverse brake levers.
They fit into the bar end of handlebars like this:

wow, that is pretty cool mod.

 

[nukezero]

Just to verify, is anyone using or know that the Samsung 18650-29E are good enough for the 750w/48V ?? It's got great capacity but worried about 2C, since at 11.6Ah pack means it can only do 23.2Ah max. This is under the 25A BBS-02 rating.

 

[teslanv]

Just to verify, is anyone using or know that the Samsung 18650-29E are good enough for the 750w/48V ?? It's got great capacity but worried about 2C, since at 11.6Ah pack means it can only do 23.2Ah max. This is under the 25A BBS-02 rating.

As long as you don't plan on riding WOT the whole time, you should be OK. If you primarily use it in PAS mode on level 3 of 9 or 4 of 9, you should be fine. I use my BBS02 this way, and it generally runs around 15 Amps max at PAS 4 of 9, and usually closer to 5 amps on the flats.

 

[nukezero]

Just to verify, is anyone using or know that the Samsung 18650-29E are good enough for the 750w/48V ?? It's got great capacity but worried about 2C, since at 11.6Ah pack means it can only do 23.2Ah max. This is under the 25A BBS-02 rating.

As long as you don't plan on riding WOT the whole time, you should be OK. If you primarily use it in PAS mode on level 3 of 9 or 4 of 9, you should be fine. I use my BBS02 this way, and it generally runs around 15 Amps max at PAS 4 of 9, and usually closer to 5 amps on the flats.

...hrrm.. this ain't gonna work for me then. I intend to WOT all the way to work. I live in orange county, so it is miles and miles of paved bike lanes...

 

[teslanv]

Just get a 30AH Ping and be done with it.

 

[jateureka]

Nukezero,
If you read through previous posts others here have said these units are not the best for running WOT for extended periods as they tend to get quite hot because they do not have a lot of copper mass and they tend to draw a lot more current than the nominal rating.

They work better using PAS and bursts of WOT when required such as taking off from the traffic lights.

If you want to run WOT then maybe you would be better with a hub motor or the GNG mid drive.

 

[Zippy Hawaiian]

Just to verify, is anyone using or know that the Samsung 18650-29E are good enough for the 750w/48V ?? It's got great capacity but worried about 2C, since at 11.6Ah pack means it can only do 23.2Ah max. This is under the 25A BBS-02 rating.

How about this one instead, 14Ah with 29e cells, quite small

http://em3ev.com/store/index.php?route=product/product&path=35&product_id=128

 

[amigafan2003]

Just to verify, is anyone using or know that the Samsung 18650-29E are good enough for the 750w/48V ?? It's got great capacity but worried about 2C, since at 11.6Ah pack means it can only do 23.2Ah max. This is under the 25A BBS-02 rating.

As long as you don't plan on riding WOT the whole time, you should be OK. If you primarily use it in PAS mode on level 3 of 9 or 4 of 9, you should be fine. I use my BBS02 this way, and it generally runs around 15 Amps max at PAS 4 of 9, and usually closer to 5 amps on the flats.

...hrrm.. this ain't gonna work for me then. I intend to WOT all the way to work. I live in orange county, so it is miles and miles of paved bike lanes...

You don't want to run WOT on the 48v/750w BBS02. PAS only will be fine as it uses only half the power as the throttle, but full throttle will overheat quickly.

 

[beazee]

The cables are directly underneath the downtube. As a result, there is no way I could mount the mid-drive kit then because it would press against the cables.

There's enough space for cables between the bottom bracket and the Bafang motor casing. In fact the power cable is routed there in my project.
http://endless-sphere.com/forums/viewtopic.php?f=28&t=50104&p=871397#p871397

 

[teslanv]

Nukezero,
If you read through previous posts others here have said these units are not the best for running WOT for extended periods as they tend to get quite hot because they do not have a lot of copper mass and they tend to draw a lot more current than the nominal rating.

Just want to point out jateureka is referring to the motor, here, not necessarily the battery. He is correct, though. The Bafang does not like to be run at WOT for prolonged durations, and will overheat and cut out on you.

 

[Warren]

I think you guys need to clarify what you are saying about the Bafang. I guarantee it can be run WOT all the time...no problem. What you can't do is run it continually in high gears. It is a "750 watt" motor. You need to be averaging 750 watts or less. If you are pulling the full 25 amps at 48 volts continuously, you are averaging 1200 watts, and you are going to ruin it.

And if you are going to pull 25 amps continuously from a 30 amp Ping pack, it will have a very short life.

Buy one of these,

http://www.ebikes.ca/shop/ebike-parts/motors/mtc100r26.html

and some hobby lipo packs and ride it like a scooter to work every day.

 

[teslanv]

I think you guys need to clarify what you are saying about the Bafang. I guarantee it can be run WOT all the time...no problem. What you can't do is run it continually in high gears. It is a "750 watt" motor. You need to be averaging 750 watts or less. If you are pulling the full 25 amps at 48 volts continuously, you are averaging 1200 watts, and you are going to ruin it.

And if you are going to pull 25 amps continuously from a 30 amp Ping pack, it will have a very short life.

Buy one of these,

http://www.ebikes.ca/shop/ebike-parts/motors/mtc100r26.html

and some hobby lipo packs and ride it like a scooter to work every day.

To me WOT means running at 25A (the Max the controller will allow/supply) -which is well beyond the 750W the motor is rated for. If you are implying that you can run the motor at 750W full time, then I would agree, but this would not be at Wide Open throttle. For me, WOT = 1200W (48V x 25A) - and at this power usage, the motor WILL overheat. I have had the motor cut out on me after riding WOT several times. It usually picks back up in less than a minute, once it cools down.

 

[Warren]

teslanv,

"To me WOT means running at 25A (the Max the controller will allow/supply)"

Which is why I said we needed to clarify what we mean by WOT. The acronym stands for wide-open-throttle. With a motor running through the gears, throttle position, and load are two entirely different things.

 

[teslanv]

OK. I suppose if you were geared low, you could have the throttle wide open, but controller would limit Crank RPM to its max of ~120, and would thus draw less than 25A.

 

[Warren]

Yup. A bike with the Bafang can go 30 mph. But anybody who thinks they are going to average 30 mph on anything but a dead flat, windless road, for more than a few minutes, is going to be disappointed.

My car can go 100 mph, but it wouldn't last the week at that speed.

 

[Rollodo]

Yup. A bike with the Bafang can go 30 mph. But anybody who thinks they are going to average 30 mph on anything but a dead flat, windless road, for more than a few minutes, is going to be disappointed.

My car can go 100 mph, but it wouldn't last the week at that speed.

You can only have a 'windless' effect when you have tail wind supporting your speed - in other words, a 30 mph tail wind. After a 50-km trip with a 30 km/h average (max being about 45 km/h), I cannot think that anybody would be comfortable on a bicycle at speeds exceeding that, unless it's a rural area.

 

[nukezero]

But what if assuming no head-wind, purely flat and paved road, lightweight bike(~26lb) + 155lb rider (me) going and 30mph... on a 48/11T cog, you're saying the BBS02 will cut out after maybe 5 minutes ?!?!?

 

[Rollodo]

But what if assuming no head-wind, purely flat and paved road, lightweight bike(~26lb) + 155lb rider (me) going and 30mph... on a 48/11T cog, you're saying the BBS02 will cut out after maybe 5 minutes ?!?!?

One can only assume no head wind in a controlled environment (a lab, vacuum conditions). We speak of wind mostly as it relates to resistance (another thing is cooling, but that's besides the point). You will always have resistance. The faster you go, the greater the resistance. It becomes impractical going over a certain speed, because the motor starts consuming disproportionally higher amps, due to higher resistance, resulting in higher wattage, more heat, less efficiency, and drastically reduced performance.

 

[teslanv]

But what if assuming no head-wind, purely flat and paved road, lightweight bike(~26lb) + 155lb rider (me) going and 30mph... on a 48/11T cog, you're saying the BBS02 will cut out after maybe 5 minutes ?!?!?

It's going to depend on how much you are helping it. If set up for PAS level 4 of 9 you could probably get pretty close to 30 MPH on the flat, and only use around 750W of motor power, if your legs are supplying another 200+ Watts. It's right at the limits of the drive, though. You may find that 25 MPH is "fast enough", and will provide much better economy and cooler motor, and better match your natural pedal cadence.

 

[nukezero]

Alright, I guess I will limit myself to those speeds then. But if I need the extra burst, then it's there. Someone should make a heatsink to absorb the heat from the motor externally. I bet it can be done, in a shape of a tube that runs parallel below the downtube, that is made in copper.

Then the next question is, if the 29E battery is worth it. It's either that, or I spend the time and money to build my own 25R.

 

[teslanv]

Not sure if you have ruled out LiPo yet. I know ES generally steers noobs away from LiPo, because of safety concerns, but if you educate yourself on proper care and maintenance of LiPo, it is a wonderful solution for higher current systems.

I chose LiPo for my first build. I have been happy with my decision thus far. The Up-front cost is small, and the packs provide light and powerful energy in a small package. And they are way more than enough to handle the 25A BBS02 needs.

It is a decision one must make for themselves and the people that live around them, however, since a mis-step can be catastrophic. - Just thought I would share the option with you.

The reality is that almost half of those surveyed recently use LiPo. http://endless-sphere.com/forums/viewtopic.php?f=5&t=57943