New Bafang Crank-Drives

[hachiko]

I'm a beginner to the e-bike world and am looking to convert my titanium 29er hardtail to an e-bike via the 750W BBS02 kit with a hefty battery (preferably somewhere in the 20-25ah range).



After reading through all 103 pages of this thread, i'm motivated to go ahead with my build. It seems that the BBS02 connects through the BB via compression instead of using the BB's threads. I'm worried that the compression will create notches in the frame's BB and thereby ruining my Ti frame. Is this a big deal in case I want to put a regular crankset back in someday?

Really great community, thanks for your advice!

 

[dumbass]

dumbass, yes...your phases are shorted.

OK, thanks for the info. That's what I thought. We are both talking about the "motor" phases and not the controller......Right?

Bob

 

[droner]

I'm a beginner to the e-bike world and am looking to convert my titanium 29er hardtail to an e-bike via the 750W BBS02 kit with a hefty battery (preferably somewhere in the 20-25ah range).



After reading through all 103 pages of this thread, i'm motivated to go ahead with my build. It seems that the BBS02 connects through the BB via compression instead of using the BB's threads. I'm worried that the compression will create notches in the frame's BB and thereby ruining my Ti frame. Is this a big deal in case I want to put a regular crankset back in someday?

Really great community, thanks for your advice!

Hachiko, I have the exact same bike with a Bafang 750w motor from Lectric Cycles and a 25AH 50.4v battery in a triangle bag from Cellman (EM3EV.com) and I love it. I don't think the installation has harmed the frame in any way and one could easily reverse the installation and restore the bike to its original configuration. I get at least 60 miles from the pack using PAS level 3 of 5 mostly. I've changed my chain wheel to a 42t--from the factory 48t-- and like the increased hill climbing power but pay some in the fast cadence speed at speeds over 25mph. Anyway, try it, you'll like it.

 

[samsavvas]

It seems that the BBS02 connects through the BB via compression instead of using the BB's threads. I'm worried that the compression will create notches in the frame's BB and thereby ruining my Ti frame. Is this a big deal in case I want to put a regular crankset back in someday?

I think it's probably more accurate to say that the BBSxx attaches via 'friction' than by 'compression'. Yes - compression forces are exerted on the end of the BB shell but it's that friction against the shell's faces that holds it in place. I know it seems a bit pedantic but this use of rotational 'friction' is very effective. IMHO there's no chance it will distort the shell and if it's a standard 'English' 68mm (or 73mm) it should fit fine and the threads will not be damaged. From memory the BBxxx contact surfaces have tiny bumps on them - I think to allow some 'bite' on the BB face. These are tiny and I doubt that there's the slightest chance you'd notice any significant damage or deformation to the faces and certainly nothing that would functionally effect subsequent restoration to a normal BB/crank arrangement. Ti is much harder than the stuff BB shells are normally made from anyway - right? It'll certainly be much, much tougher that whatever it is that the BBSxx casing's made from!

Savvas

 

[hachiko]

Droner, congrats on your build. I bet it must be a pretty sweet ride. I can't wait till they restock the BBS02 again so I can complete my build. Got a picture of your ride to share with us? 60 miles is pretty decent. I'm hoping with some spirited pedaling and economical use of PAS, I might get close to 80-90mile range out of the same battery pack.

Btw, how did you convert to a 42t chainring? Via this: http://www.alcedoitalia.it/shop/guarniture/corona-42-denti-per-bafang-centrale-bbs01
Or this: http://endless-sphere.com/forums/viewtopic.php?f=28&t=50104&start=2500#p894851

Savvas, good to hear that it would have minimal if any deformation to the face of BB.

Cheers!

 

[teslanv]

I just logged a 36-mile ride on my 12S-10Ah battery (444 Whrs). With 25Ah (1250 Whrs) you should be able to get close to the 100-mile range with a PAS setting of 3/9.

And I weight about 190 lbs.

 

[tahustvedt]

I have a Bafang BBS01 250 W on the way. I'm just interested in the technology, really and want to test it in case my dad wants me to upgrade his bike later. I haven't decided which bike to try it on though. It's going to be either a Surly Cross Check oamy fatbike I'd have to mill down the fatbike bottom bracket to make it fit though. I guess I'll pop it in the Cross Check first to see how I like it .

 

[hachiko]

And now onto the battery packs.

I've considered just going with cellman's 25ah triangle pack, but given the long shipping times and costs ($220+ shipping to CA, USA), I'm considering doing a custom battery pack just like many in this forum have done.

The setup I'm looking at is a 12s3p using 6 packs of 6s1p 8000mah lipo from HK.
http://www.hobbyking.com/hobbyking/store/__20647__ZIPPY_Flightmax_8000mAh_6S1P_30C_USA_Warehouse_.html
So completed it would be a 24ah 44.4v pack; 2 in series and 3 in parallel.

I've seen some builds connect the packs in parallel first, then connect those groups serially. Would there be any problems with doing the reverse: connecting the pairs of packs in series first, then the 3 groups in parallel?

To do series first, then parallel, I would need this:
http://www.hobbyking.com/hobbyking/store/__18603__HXT4mm_Battery_Harness_14AWG_for_2_Packs_in_Series.html

And then a parallel harness to connect 3 bat packs together. I see harnesses for connecting 2 packs together, but do they make them in more than 2?
http://www.hobbyking.com/hobbyking/store/__18604__HXT4mm_Battery_Harness_14AWG_for_2_Packs_in_Parallel.html

I understand I could go with http://lipoconnectionsolutions.com/Lipo-Harnesses-0quote.htm and do a custom quote here, but was looking to see if there was something simpler I could purchase off the shelf.

If not, is it possible to buy this:
http://www.progressiverc.com/parallel-6x-hxt-4mm-bullet-charge-cable.html
And then convert the banana plug end to become a hxt connector. Thereby creating a 6x parallel harness. (a 6x parallel harness is nice as it would give me the flexibility to add addition packs in the future for even more capacity!)

Also, any recommendations for what battery management system to use in this setup?

Trying to get this right as it seems working with Lipo can be quite a perilous road. Thanks for your advice!

 

[tomjasz]

I have a Bafang BBS01 250 W on the way. I'm just interested in the technology, really and want to test it in case my dad wants me to upgrade his bike later. I haven't decided which bike to try it on though. It's going to be either a Surly Cross Check oamy fatbike I'd have to mill down the fatbike bottom bracket to make it fit though. I guess I'll pop it in the Cross Check first to see how I like it .

Please share where on the planet you are. It will be helpful if you ever need assistance and it's also very cool to know how users are now covering the planet. Beautiful photos and nice bike as well! I'm looking forward to your adventures with your BBS01!

Tom

 

[tahustvedt]

I've updated my prfile. I live in Northern Norway. Slightly above 69°N.

 

[droner]

Droner, congrats on your build. I bet it must be a pretty sweet ride. I can't wait till they restock the BBS02 again so I can complete my build. Got a picture of your ride to share with us? 60 miles is pretty decent. I'm hoping with some spirited pedaling and economical use of PAS, I might get close to 80-90mile range out of the same battery pack.

Btw, how did you convert to a 42t chainring? Via this: http://www.alcedoitalia.it/shop/guarniture/corona-42-denti-per-bafang-centrale-bbs01
Or this: http://endless-sphere.com/forums/viewtopic.php?f=28&t=50104&start=2500#p894851

Savvas, good to hear that it would have minimal if any deformation to the face of BB.

Cheers!

Hichiko, here are a few pics of my bike. I agree you should get much further on a battery than I've reported. I weigh 220 and use throttle to power up hills. I've also never run my battery down below about 46v. I'm still figuring it
all out. I have a Watt's Up meter wired between my motor and battery and am slowly building some data on watts per mile. In my drive train picture you will see a large 42t add-on sprocket made by OneUp C0mponents. Combined with the Alcedoitalia 42t chain wheel I'm set to climb Mt.Everest, but I'm likely to put on a 44T in front next, part of my experiment to have the greatest hill climbing prowess and still be able to keep the cadence reasonable for pedaling up to 30mph. Right now I pedal comfortably up to 27 or so.

 

[joshseitz]

Combined with the Alcedoitalia 42t chain wheel I'm set to climb Mt.Everest

Droner, how much was shipping for the 42t chainring from Italy? And all I've seen is this 42. Anyone know if there are other sized being produced?

 

[m4s73r]

Eride on this forum makes an adapter to fit whatever size chainring you want.

 

[droner]

Combined with the Alcedoitalia 42t chain wheel I'm set to climb Mt.Everest

Droner, how much was shipping for the 42t chainring from Italy? And all I've seen is this 42. Anyone know if there are other sized being produced?

Joshseitz, the chain wheel was 79 euros plus 35 euros for shipping. If I had it to do again I'd buy a 130 BCD adaptor and a RaceFAce NarrowWide chainring. They
come in all sizes and are heavier. The one from Italy has fairly thin teeth and isn't as robust as the RaceFAce ones. It does have an offset to the inside which helps
the chain line a little. Also less expensive. I don't know if it comes in other sizes.

 

[CellBalance]

Error code 30 is listed in C950 display specification:
http://www.greengobikes.com/wp-content/ ... cation.pdf
30 - communication has problem

Thanks borsuk. I found the same information in an earlier post by member anontrol. He determined the display unit had a problem since everything worked correctly when he substituted a second display unit he had. His display unit was a C961, the same unit I have.

I have since ordered a new display unit from http://www.greenbikekit.com and will deal with the defective unit if the replacement unit corrects the problem.

It seems the dreaded "error 30" message spells death to the display (and for practical purposes, the motor as well since you can't even turn controller on without a functional display) . And what with a change from all-black-wire harness to newer multicolored/different connectors/harness and matching displays, getting functionality for older model motors seems problematic, especially if the older displays are no longer produced and existing stocks from dealers get sold out.

If any of the bright lights here have a strategy to fix the error 30 "connection problem" please speak up. Inquiring minds would like to know how to hack-a-fix on the displays they have in hand with that error message. I'm one of them.

I'm thinking maybe it would be possible to hotwire a simple on/off switch for starters.
-Addicted to my ride and now in withdrawl

 

[Tom L]

Maybe. My error 30 was because I fried the serial comms FROM the motor to the display. I could still change the PAS level in the short time before the error comes up on the display, right after power on. i.e. comms from the display to the motor was still working. If you can do this you have a problem in your motor (controller) not the display. A new display did not fix the problem. A new motor controller did.

 

[hachiko]

Droner, beautiful bike and nice 42t rear cog. I've got a 11-36t in the back too and might upgrade to 11-42t to get more hill attacking power. I bet you're attacking some really tough hills/mountains/trails now aren't ya? Do folks on this board share their strava routes? Would love to see what ppl are able to do with their e-bikes now.

Will check out the OneUp Component 42t rear cassette cog. Here's a cheaper, lower quality cassette cog if you're on a budget
http://www.ebay.com/itm/41-Tooth-Cog-for-Mountain-Bike-Cassette-41t-Sprocket/251408161635?

79+35 euros for a 42t front chain ring does sound excessive. Will probably look into a 130 or 104 BCD adaptor since it affords the flexibility of adding a chainring size of your choice and allow replacement in the future.

 

[teslanv]

My opinion is that anything more than a 36T Large rear Cog is unnecessary with the 750W Kit. This thing pulls like a horse in low gear. Literally. 1hp.

 

[hachiko]

Thanks for your perspective Teslanv. Will try without 42t in the rear first and then judge if it's necessary after getting a few rides in. Nice to have options though!

Any thoughts on wiring up a DIY LiPo battery per my questions a few posts back?

 

[Kepler]

My opinion is that anything more than a 36T Large rear Cog is unnecessary with the 750W Kit. This thing pulls like a horse in low gear. Literally. 1hp.

It depends on what your target top speed is. I like to be able to commute at 40kph to 45kph and burst to 50kph. For this to work, I run a 44 tooth with an adapter on a 29er with 2.25" tires. A 36T wouldn't work for me for the target speeds I am after.

I am considering the Italian CNC 42 tooth for the sole purpose of improving my chainline. Not keen on the $180 AUD landed price but for me it may well be the final piece of the puzzle for this bike to be close to perfect for my needs.

 

[teslanv]

My opinion is that anything more than a 36T Large rear Cog is unnecessary with the 750W Kit. This thing pulls like a horse in low gear. Literally. 1hp.

It depends on what your target top speed is. I like to be able to commute at 40kph to 45kph and burst to 50kph. For this to work, I run a 44 tooth with an adapter on a 29er with 2.25" tires. A 36T wouldn't work for me for the target speeds I am after.

I am considering the Italian CNC 42 tooth for the sole purpose of improving my chainline. Not keen on the $180 AUD landed price but for me it may well be the final piece of the puzzle for this bike to be close to perfect for my needs.

Let me clarify, as I think you misunderstood my comment:
A Large Rear Cog would have no effect on the top speed of the bike, it would lower the top speed of the low gear, allowing for more torque. Top speed is still goverened by wheel size and small rear cog.

 

[Kepler]

Yes I did misunderstand. Thanks for clarifying.

 

[tomjasz]

I need to ask a really n00b question. I find that I almost never shift. 95% of the time I use 7th gear, 7spd, and start off with max assistance. All flat ground and with no inclines. I have fairly frequent stop signs to deal with. I slow to 20kph as far back as I can and still have a view and also use full throttle to 32kph to motor through when possible. I run any stop sign I have a 45m clear zone on for cross traffic. This cross traffic is in 48-55kph. If I did use my gears, when forced to a full stop, which combination of gears would give me the fastest acceleration with BBS01 350W??

I hope I'm making sense.

.






RANT:
This is life changing. I'm completely independent for all my errands and needs. If you have any aunts, uncles and family that has given up biking, has any sense of adventure, has sufficient balance, and ought not be behind the wheel of a cage, encourage them. Help them get a E Bike. Pedal forward bikes are so stable! In a small-town environment, 25,000 here, everything is in reach.

 

[skitime]

Help!! I have a Bafang 750 watt. I bought it from LeGrand at Lectric Cycles. I have only ridden it a few miles. At first everything seemed fine. Then I started noticing in situations where the motor might draw a few more amps like up a hill the motor would shut down. It would seem to quickly come back to life it you would pedal backwards or shut it off. Now the problem is getting worse. I cannot use the throttle anymore because it would shut off the motor. I disconnected the throttle to see if that affected anything but it did not. The motor never feels even slightly warm. Last weekend we did a 12 mile Rail/Trail that was nearly flat and I only was using the PAS at level one. Near the end of the trail, the motor would shut off occasionally even a PAS level 1. Now I am unable to complete a ride around the block without constant motor shutdowns. When it happens I can hear a click in the motor. I am not sure if this is a sound of a switch/relay or the sound of the motor quitting. Any ideas? This is very frustrating. I am in Pennsylvania and LeGrand is in Arizona and often hard to get a hold of.

To make matters worse, I also got a NuVinci N360 from LeGrand. He laced the hub in a new rim. It arrived and was installed before the motor ever arrived. It is also defective. It was slipping when you pedal. So after weeks of emails, I am dead in the water with the NuVinci as well with no progress on getting a replacement or a repair. I have been using the Bafang with the old 7 speed hub. Even Fallbrook Technology maker of the NuVinci seems to be unresponsive. I sent them an email. I got a reply from a Jeremy Leffingwell at Fallbrook Technologies but he never replied to a follow up question.

 

[Chalz]

skitime,
I had those exact symptoms. I took me weeks to figure it out. It ended up being a poor connection in the wire that connects the motor to the battery. I replaced the stock electrical connector with an Anderson 45, shortened the wire right were it looked internally kinked and the motor has not shut down once since then. I think their was a cold solder joint that would suddenly drop the voltage below cut-off but only when the amps hit a certain level. It was fine at lower power levels. This issue progressively got worse over time until the wire and connector was replaced.

Hope that helps.
Chalz