Bafang BBSHD and gear system for fast commuter bike

[Mnaq]

Hi
I live in Sweden and use my bike to commute to work and sometimes to take two kids in a trailer.

I have had a BBSHD (1000W, 52V model=around 1200-1300 W at full throttle) for almost a year now on an old 1990 bike (Swedish Crescent Positron 5, steel frame, 28 inch, regular bike). I have had a lot of problems with the gear shifting mechanisms I have tried.

The bike runs 10-15 miles per day 5 days a week all year round and in winter on snow (down to -20C/-4F). About half of that at full throttle speed of approx 40-50 km/h (25-31) MPH. The derailleurs and chain that fit bolt-on wear down very fast with skipping gears after 1-2 months since the only ones I have found that fit directly onto the bike are for cheaper junior bikes. The bike does not have the "ear" for attaching a modern mountainbike or race derailleur. I then bought a Nuvinci N171B on Ebay (USA) that unfortunately started leaking after 2 months of use. Since I had the wheel built and shipping from USA is quite costly I cannot easily have it shipped back and forth for repairs (if it at all is possible).

So now I am looking for other reasonably priced solutions. Newer Nuvinci/Enviolo hubs, like the Heavy Duty is for the moment too expensive for me. Furthermore I like to pedal for the exercise so I need the gearing to be suitable and durable for 30 MPH at the fastest gear. What gear system can handle both low maintenance, durability and high speed (being able to pedal), preferably at a low cost (second hand?)? Should I try to find a used CVT like N171B, or use Alfine/Nexus 8 or try to convert it to a modern derailleur? What systems do modern factory built high speed ebikes use? I would be grateful for any tips. //Mattias

 

[amberwolf]

I live in Sweden and use my bike to commute to work and sometimes to take two kids in a trailer.

I have had a BBSHD (1000W, 52V model=around 1200-1300 W at full throttle) for almost a year now on an old 1990 bike (Swedish Crescent Positron 5, steel frame, 28 inch, regular bike). I have had a lot of problems with the gear shifting mechanisms I have tried.

The bike runs 10-15 miles per day 5 days a week all year round and in winter on snow (down to -20C/-4F). About half of that at full throttle speed of approx 40-50 km/h (25-31) MPH. The derailleurs and chain that fit bolt-on wear down very fast with skipping gears after 1-2 months since the only ones I have found that fit directly onto the bike are for cheaper junior bikes.

Some thoughts, in case you have not encountered this before:

The higher power middrives can very quickly wear out the drivetrain, especially if it is not shifted into the correct gears for startup or other high-torque situations, and if motor power is not stopped or rolled way back during a shift. There are a number of posts and threads about this sort of problem over the years with every kind of drive and drivetrain.

The chain will wear fastest, if the chainrings and sprockets are all steel, if any of those are aluminum they'll wear faster. Depending on usage you might get a couple-three chains worn out before you have to replace the chainrings and sprockets, and those need to all be replaced at once with the last chain replacement.. If you see excessive wear on them or have shifting problems or "skipping" of the chain you should replace them more often. .

This is also true of regular bicycles, but they generall don't see the same kind of torque loads on the wrong gears that middrives tend to cause (because it is very common for people with assist to not downshift far enough or at all...unassisted bikes are more likely to be shifted correctly because it's a lot harder to get started in the wrong gear without the motor power to do it for them).

There's another recent / ongoing thread here about a middrive wheel-jam problem that also has sprocket wear, and there are some links in it that I posted that are relevant to the above with useful info.


There aren't any drivetrains that aren't going to wear significantly faster with a middrive, as far as the drive from motor / pedals to wheel go, either belt or chain and their associated sprockets and chainrings, so you will still need to replace those whenever you are having problems with that part.

The derailers, if you are shifting like you would on an unassisted bike and backing off on pedal torque during a shift, will operate the same and last the same as they would on that unassisted bike. If you are not stopping the motor during shifts, it can damage any derailer, and even damage internal gears on an IGH, even one like the NuVinci/Enviolo (I don't know if it could cause one to leak, but it could cause the friction fluid inside and the balls to wear out faster than normal). If you don't have one installed, you may want to add the GearSensor to turn the drive off during shifts, to reduce this type of problem.

Drives like the Rohloff and other high-torque-capable IGHs can more easily take the slamming on of power from a motor (if yours doesn't ramp power up at least a bit to take up any gear lash before applying higher torque), but they are really expensive and will still not resolve any chain / sprocket problems like skipping, etc.; they only help with shifting system wear...but if shifting is done under power they'll still wear out faster than if you don't do that.

 

[Mnaq]

Hi! Thanks for your thoughts. I think I am quite good at not shifting gears under power, though I normally do that by applying the brake to cut power, or just by stopping pedaling. I also down shift when running slowly or stopping, like I would without motor assist. My derailers seem to have taken their main beating when the chain has been slipping at high speed. It seems the derailer folds back (or rather forward) quickly when this happens. Probably due to weak spring in the chain tension joint. I liked the internal hub I had because that limited the wear to a simple single speed sprocket and chain, which both are cheap in comparison with cassettes and derailleur parts and chains. I will get the bafang cable for programming the controller, but I think it has a little ramping up of power with factory setting also.

 

[amberwolf]

My derailers seem to have taken their main beating when the chain has been slipping at high speed. It seems the derailer folds back (or rather forward) quickly when this happens. Probably due to weak spring in the chain tension joint.

There are two typical causes of the chain slipping on the sprocket teeth:

If this happens equally all the time even with brand new chainring, sprockets, and chain, it means there is insufficient tension on the chain to hold the wrap around the sprocket (usually this only happens on the smallest sprockets with fewest engaged teeth). That you can fix by using less chain links as long as there is stil enough chain to wrap the combination of the largest front sprocket you'll ever use with the largest rear sprocket. If that doesn't fix it and/or it's already as short as will still work, then you can try increasing tension via the derailer with the tension adjuster screw on the derailer if it has one (but not all of the older type do). If it has no adjuster you can see if there is any way to force the derailer to sit where it will pull differently on the chain to cause more pull on the wrapped chain/sprocket, or perhaps adding a spring (like from a screen door closer, etc) from the derailer to the frame in the right place at the right angle. Also, if the derailer and it's shifter isn't adjusted correctly to line up with the sprockets, it could wear or damage things.

If it doesn't happen at first with new chain and sprockets, but only after time passes and gets worse over time, then you will need to replace at least the chain as soon as the problem starts. If it's already damaged the sprockets they'll have to be replaced at the same time. Any worn part will wear the new parts faster...

I liked the internal hub I had because that limited the wear to a simple single speed sprocket and chain, which both are cheap in comparison with cassettes and derailleur parts and chains

As long as you can be sure of shifting between power applications, you can use any of the IGHs that support your gearing ratios and torque levels...but like any other derailer system it'll need to be adjusted correctly to properly shift fully into each gear. Chalo has a recent post in another active thread describing the differences between most IGHs and the Rohloff in shifting being that the Rohloff uses detents inside the hub, while the others have them in the shifter...so the shifter not being adjusted correctly can mess up the gears in the others, but not the Rohloff.

 

[pomah]

I also live in Sweden, commute 5 days a week, I aswell was using a my bike to hitch two kids in a trailer to and from school/pre-school, but those days are now past

But to answer your question: for the last year I have been using the linkglide drive train, I just did my fist chain change, that is 1500km, I have noticed that running my chain to 0,75 on the chain wear meter, is not recommended for the linkglide drivetrain, 0,5 is a better value and then I would most likely get around 1000km of use out of a single chain. The cassette is still great, I do need to replace the 11t cog now since the missuse of the chain, but that can be done easily,

So to summarize, try to get a more moden frame, both for handling the speeds you are going in and to brake properly. It is not fun/ok to travel at the speeds you are doing with inadequate break power and/or frame stiffness. Use a nexus 5 speed IGH or the shimano linkglide shift systems, depending on what you prefer.

Get a chain extension meter to check your chain, and do not forget to regularly add lubrication to the chain and clean. I have been using squirt wax which makes the cleaning process super easy but I need to reaply it every 2 weeks, but that takes 5 min so not much work.

Summary:

Get a good frame that can handle the power you are putting.
Get IGH or external gears made for e-bikes, linkglide or shimano nexus 5 speed are tested and good.
Get tools to measure chain wear and also a good chain lubrication product
Ride your bike and enjoy

Or you get a frame with a belt-drive and just live happy ever after

 

[Mnaq]

An update to the post. I ended up buying the Shimano Nexus SG-C7000-5D (5 speed) IGH that is made for ebikes. It is really good value and it has worked well now for around 1500 miles. As a bonus I learned to build wheels since it was really hard to find the hub already in a wheel and the cost of having it made was about the same as buying the tools and parts. The hardest part was to calculate, find and buy the right spokes and nipples. Took about 5 times as long as building the wheel. With a 46t chain wheel and 24t sprocket it gives a good cadence on 5th gear at 30 MPH.

 

[Zambam]

Just saw your original post. Doesn't matter anymore since you have a Nexus but was checking / adjusting your rear derailleur hangar one of the things you've tried? My TSDZ2 mid drive was skipping in/ out of gear on my 8 spd cassette. I tried just about everything which did not help. Finally bought a cheap derailleur hanger gauge/ adjustment tool from aliexpress, found the hangar slightly bent, straightened it with the tool and it got better immediately (skips less often but still skips sometimes). It took repeated adjustment of the rear derailleur cable for it to finally settle down. Now it never skips.

 

[Mnaq]

I gave up on using derailleurs since I had to adjust the frame, or find an adapter in order to fit a good one. The Shimano Tourney that fits bolt on was simply too week for 1250 W. Since I also ride all year round in snowy and salt/sand winter an IGH with a sturdy single speed chain is so much easier. It was also a question of gear ratio. 46x14 wore down fast and gave a slightly too fast cadence. I would have had to size up the chain wheel to be able to use perhaps 18 in the rear. With the Nexus it never slips despite having a way too slack chain now after half a year. But since it is not jumping off I haven't shortened it yet.

 

[Zambam]

Good to hear the Nexus SG-C7000-5D is working well for you! I'd like to know more about you riding in snow, what kind of tires, how you keep your face, hands and feet warm?

 

[Mnaq]

Well, the easiest part is the actual riding. I use winter tires with metal small "spikes ", I think you call them studded tires. They resemble older MTB tires but with the addition of small metal studs. Here you can buy them everywhere where they sell bikes. Basically the same kind of tires we use for cars in the countryside or North in Scandinavia. Clothing is more difficult. I also like the middrive system since it allows you to go through deep snow if there has been snow drift or a bike road has not been ploughed. It allows the bike to be strong and at the same time not too fast. But on flat icy road I can ride 30 MPH without fear of falling.

I use downhill skiing pants together with a Gore Tex winter jacket made for professionals like road construction workers. I want the reflexes and the fluorescent colors, and they are really durable. There are no road lights on the road and if there is no snow, it is REALLY dark. The brand is Taiga but it might be Swedish. The jacket can also be used if it is not so cold since the warm lining can be removed. For hands I use skiing gloves or if it is below -10 C mittens for skiing/snowmobile. I have been contemplating some kind of wind protection for the hands mounted on the handlebar like on Enduro motorbikes. Especially using the thumb throttle is bad if it is really cold. The thumb cools down fast. The face is complicated. I use a downhill alpine helmet (all year round actually) but that was partly because I have a big head and dreads. I would like to have a helmet with face protection like a downhill bike helmet or Enduro helmet. But it has to be not so ventilated as is often the case. A real motorbike integral helmet would be good of course but is also quite heavy. So as of now I use my alpine helmet with balaclava ("robbers mask") with skiing goggles or a wind "cone" (vindstrut in swedish) if is below -10 C. This last thing looks ridiculous but is actually the best item below -10C. It is an old invention from before WW2. Basically it is a rim projecting out 10 cm out from your face that creates an air cushion of still air in front of you. Advantage is it cannot fog up from your breath. I have not made the balaclava work perfectly. The speed matters a lot, so if you ride at 30 MPH at -20 C for more than just a few minutes you need really warm clothes. Groin also a weak spot so I use extra layers there. I actually have some Tibetan sheep fur pants for really cold days. They are so warm you can't use them for a walk above -20. Problem is you are not exactly agile in them. Good luck!

 

[aae34]

Especially using the thumb throttle is bad if it is really cold. The thumb cools down fast.

Wouldn't cruise work? If you're not running w/bbs-fw yet, i'd suggest taking a look at it(your countryman wrote it):

GitHub - danielnilsson9/bbs-fw: Open source firmware for multiple electric bike motor controllers.

Open source firmware for multiple electric bike motor controllers. - danielnilsson9/bbs-fw

github.com

 

[amberwolf]

I have been contemplating some kind of wind protection for the hands mounted on the handlebar like on Enduro motorbikes.

The SB Cruiser : Amberwolf's 2WD Heavy Cargo Trike & Dog Carrier

I haven't used the electric braking on the "new" generic controller much due to the extreme excessive heating (goes up about 10 degrees C every time I use it...peaks have been nearly 70C even when starting at 8C on the last several cold mornings). I'm probably going to disconnect it from the...

endless-sphere.com

There are also a number of "winterizing" threads with probably helpful info.

 

[Zambam]

Well, the easiest part is the actual riding. I use winter tires with metal small "spikes ", I think you call them studded tires. They resemble older MTB tires but with the addition of small metal studs. Here you can buy them everywhere where they sell bikes. Basically the same kind of tires we use for cars in the countryside or North in Scandinavia. Clothing is more difficult. I also like the middrive system since it allows you to go through deep snow if there has been snow drift or a bike road has not been ploughed. It allows the bike to be strong and at the same time not too fast. But on flat icy road I can ride 30 MPH without fear of falling.

I use downhill skiing pants together with a Gore Tex winter jacket made for professionals like road construction workers. I want the reflexes and the fluorescent colors, and they are really durable. There are no road lights on the road and if there is no snow, it is REALLY dark. The brand is Taiga but it might be Swedish. The jacket can also be used if it is not so cold since the warm lining can be removed. For hands I use skiing gloves or if it is below -10 C mittens for skiing/snowmobile. I have been contemplating some kind of wind protection for the hands mounted on the handlebar like on Enduro motorbikes. Especially using the thumb throttle is bad if it is really cold. The thumb cools down fast. The face is complicated. I use a downhill alpine helmet (all year round actually) but that was partly because I have a big head and dreads. I would like to have a helmet with face protection like a downhill bike helmet or Enduro helmet. But it has to be not so ventilated as is often the case. A real motorbike integral helmet would be good of course but is also quite heavy. So as of now I use my alpine helmet with balaclava ("robbers mask") with skiing goggles or a wind "cone" (vindstrut in swedish) if is below -10 C. This last thing looks ridiculous but is actually the best item below -10C. It is an old invention from before WW2. Basically it is a rim projecting out 10 cm out from your face that creates an air cushion of still air in front of you. Advantage is it cannot fog up from your breath. I have not made the balaclava work perfectly. The speed matters a lot, so if you ride at 30 MPH at -20 C for more than just a few minutes you need really warm clothes. Groin also a weak spot so I use extra layers there. I actually have some Tibetan sheep fur pants for really cold days. They are so warm you can't use them for a walk above -20. Problem is you are not exactly agile in them. Good luck!

Great post with a few things I did not expect or have heard of. Going 30 MPH on flat icy road w/o fear of falling is insane! I don't think I've gone faster than 22 MPH on my TSDZ2 mid drive on dry pavement in the summer.

What's this wind "cone" vindstrut thing? Do you have a link or photo. I've tried many things to keep my face/ head warm (doesn't get that cold here, 20 F days are rare). The warmest is my full face Shoei motorcycle helmet with flip up/down shield. It's only drawback is weight @ 3.2 lbs and it fogs unless I keep it cracked open a little.

Feel free to go more in details on the other items you talked about, provide links/ photos if you can. I am interested in all of them.

 

[Mnaq]

Wouldn't cruise work? If you're not running w/bbs-fw yet, i'd suggest taking a look at it(your countryman wrote it):

GitHub - danielnilsson9/bbs-fw: Open source firmware for multiple electric bike motor controllers.

Open source firmware for multiple electric bike motor controllers. - danielnilsson9/bbs-fw

github.com

Yes. I need to reprogram my controller. That link looks really interesting. Among other things so that full 100% power is on the 9th power level. Now I have the 9th plus throttle making it full speed. I also need to change the constant continuous current up to 30 A from 25 A. Battery claims it has 40A continuous discharge max (some inferior UPP ones have 30A only like my older no name battery). If it is cold you need to keep warm so pedaling is needed all the time. It is also free daily exercise. Has anybody tried the GitHub programming by Daniel Nilsson?

 

[aae34]

Has anybody tried the GitHub programming by Daniel Nilsson?

Yes, it's better than bafang fw, imo.

BBS-FW: Open Source Firmware for BBSHD/BBS02 Controller

This open source project is finally ready for release! This firmware is intended to replace the original Bafang firmware on BBSHD/BBS02 motor controllers and can be flashed using the standard programming cable. Almost all functionality of original firmware has been reimplemented and additional...

endless-sphere.com

 

[Mnaq]

Great post with a few things I did not expect or have heard of. Going 30 MPH on flat icy road w/o fear of falling is insane! I don't think I've gone faster than 22 MPH on my TSDZ2 mid drive on dry pavement in the summer.

What's this wind "cone" vindstrut thing? Do you have a link or photo. I've tried many things to keep my face/ head warm (doesn't get that cold here, 20 F days are rare). The warmest is my full face Shoei motorcycle helmet with flip up/down shield. It's only drawback is weight @ 3.2 lbs and it fogs unless I keep it cracked open a little.

Feel free to go more in details on the other items you talked about, provide links/ photos if you can. I am interested in all of them.

I will take a picture of myself with the gear and and post it. I forgot the feet. There I use pretty standard winter low boots/high shoes (see picture) and if it gets below -10 C snow mobile boots of the good value brand Raven see link of the model I have below. They are really warm but you can't exactly dance ballet in them so they are a bit too much if you have to go shopping in the city stores from the office.

sledstore

 

[Zambam]

Next to your ebike and trailer if possible.

 

[Mnaq]

Wouldn't cruise work? If you're not running w/bbs-fw yet, i'd suggest taking a look at it(your countryman wrote it):

GitHub - danielnilsson9/bbs-fw: Open source firmware for multiple electric bike motor controllers.

Open source firmware for multiple electric bike motor controllers. - danielnilsson9/bbs-fw

github.com

Hi. I downloaded the STC program for running Daniel Nilssons firmware but Norton complains the STC contains the virus IDP.ALEXA.54 and put it into quarantine. Has anyone run into this problem?

 

[wturber]

Hi. I downloaded the STC program for running Daniel Nilssons firmware but Norton complains the STC contains the virus IDP.ALEXA.54 and put it into quarantine. Has anyone run into this problem?

I suggest scanning the file with different tools. I'd also check with whomever it is that publishes the file and get an explanation from them. Given how uncommon and niche the file you are talkin about is, I'd bet this is a false positive. That said, it is good to be careful.