My bike goes too fast for me to have pedal input. Can I change this?

duggie

Active Member
Region
United Kingdom
All is well with my bafang mid drive conversion. I'm still testing and learning, but my problem is that once I start pedaling and get the PAS, the bike goes faster than I want and can pedal, so my pedaling does nothing, and that is in level one with my lowest gear. I'd like to assist but I can't.

On my Keteles fat tyre bike I can assist comfortably, but on this bafang I pedal and then it soon speeds up beyond me, so it is a series of a few pedals and then let the motor cut out, then a couple of turns to kick the motor in again.

On my control panel display there is no PAS adjustment, so it seems I am stuck with it. Levels above 1 are just even faster, so no good at all.

I want to lessen the power assist so that I can have some input. The only time I can have input is on a hill.

It would be great to have a PAS level for hills, and a PAS level for on the flat.

The only thing I can think is to lower the max speed option on my control panel.

Are these PAS levels simply to do with speed, ie if your going at 10mph you use level one, or if you want to do 25mph you choose level 4, say?

Basically, the motor will not let me join in unless it's a very steep hill. What's going on?
 
Perhaps some tuning would help. It was a long time ago, but my BBS02 kit with the C965 display came with 3 PAS levels, and all three would race past 20 mph with ghost pedaling. When optioned out for 9 PAS levels, PAS 1 would top out around 14 mph, but at 12 mph, it still required some moderate input. This was OK for me.

More can be done if you buy a programming cable and have a windows PC to adjust some firmware registers. These will lower the motor assist at the lower PAS levels. I didn't want to do any of that,
 
Your lowest gear is your easiest to peddle. When you go up a hill you want the low gear.
So, if you are not already doing so use a harder to peddle gear (small rear cog).

I have tried a cadence sensor Bafang and I could set it so it was requiring input from my legs.

You said you did a conversion? Then buying the UART to USB cable sounds like a no brainer to start on the fix.
 
You will need to do some research and learn how to program the motor, will be well worth it and is one of the big advantages to this motor, good luck
 
So, short story, because this can involve so much, I'm wondering how many PAS levels you have? And just to confirm, we are talking about a Bafang mid drive, right?
 
@duggie the overpowering you are experiencing are just a normal byproduct of the Bafang settings not being designed for a cyclist wanting exercise. The settings are actually quite a bit more complex than just level 1 to X mph, level 2 to Y mph and so on. But there are tutorials to help you along.

Here. The follow-on article to this one, linked at that article, has a 'version 2' set of settings that are REALLY dialed back. Only 450w of pedal assist at PAS 9

 
I have a bafang mid drive with the bafang display panel. I went on Youtube. There seems to be two bafang display panels, mine is the eco/sport type. I watched two videos, one for each panel. The none eco/sport type does have option to change the PAS level, but the eco/sport model doesn't, and this German guy was saying he had the same problem re the PAS levels, and he was resorting to having to 'fool' the controller by changing his tyre size and speed limiter. No PAS option seems crazy; couldn't make it up. Just thought maybe there was something obvious I wasn't seeing.

I can't even think about learning programming, my head just isn't wired that way at all.

Re the reply about using my gears to achieve PAS, 1st gear is great when I'm on a steep hill, but then when on flat and shift to 6th gear (my smallest cog) it still out runs me and i would have to be pedalling absolutely furiously, and even then I cant't keep up.

I'll try lowering the speed limit like that German guy suggested and post how it goes. I'm reluctant to fiddle with any settings, such is my luck with that type of thing.
 
Duggie where do you live? That is a popular motor and good chance you could find someone to help you

Other option might be get a different display that has the 9 level pas option

And you are definitely riding in eco/green right?
 
I can't even think about learning programming, my head just isn't wired that way at all.
People call it programming but its not. Its just a settings interface and you have a complete blueprint of what to do. All you are doing is filling in boxes and pressing 'Save'.

Your display cannot get to this settings interface. What it does is a tiny fraction of what can be done. Honestly, I'd call it wasted effort for what you want to accomplish. Wrong tool for the job.
 
Unplug your display and check the display connection. It's either...
UART- ROUND in shape
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CANBUS - PENTAGON in shape
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If it's round (UART) you can change the PAS settings.
For example my PAS 1 cuts out at around 6mph in 1st gear and I have it set up that I input (exercise) pedaling in all PAS 1 thru 8.
I use 9 at 100% for the throttle.
 
I have a bafang mid drive with the bafang display panel. I went on Youtube. There seems to be two bafang display panels, mine is the eco/sport type. I watched two videos, one for each panel. The none eco/sport type does have option to change the PAS level, but the eco/sport model doesn't, and this German guy was saying he had the same problem re the PAS levels, and he was resorting to having to 'fool' the controller by changing his tyre size and speed limiter. No PAS option seems crazy; couldn't make it up. Just thought maybe there was something obvious I wasn't seeing.

I can't even think about learning programming, my head just isn't wired that way at all.

Re the reply about using my gears to achieve PAS, 1st gear is great when I'm on a steep hill, but then when on flat and shift to 6th gear (my smallest cog) it still out runs me and i would have to be pedalling absolutely furiously, and even then I cant't keep up.

I'll try lowering the speed limit like that German guy suggested and post how it goes. I'm reluctant to fiddle with any settings, such is my luck with that type of thing.
Sounds like the DPC18.UART
 
 
I have a similar set up but with a the DPC-18 display. I'm not sure which one the OP has. I can walk him through the settings if he has this one. It only takes about 20 seconds.
I can set it for 3, 5 or 9 PAS, no programming needed. I use the 9 levels now but back it down to #3 (out of 9) most days so I am always pedal assisting. If I go to 5 (out of 9) then I'm doing 28 mph so pedaling is hardly worth it. A 9 out of 9 I'm doing 36 mph so I just let it do it's thing and enjoy.
 
It seems like he has 2 bikes, that's why I wanted to confirm the one he's asking about is his Bafang conversion, which I think is a BBSHD.
 
bafang mid drive conversion.
The newest kits aren’t main stream from what I’ve seen.
Where are you seeing BBSxx mentioned by the OP?
This does get obfuscated by another poster jumping in with an Ultra. But we’ve coached and helped Duggie before and he bought a BBSxx. He confirmed.

AHicks.........Bafang mid drive kit, 1000w 52 v. It is powerful, and normally I would have gone for less, but I have a very specific need for it. My journeys will only be a mile, off road, and I don't want to go faster than 5 mph. But I have to climb a very steep hill, and I'm getting older. Only a bicycle will fit this path. Occassionally, I'll go with gf to a cycle path on our little tours, so I can use it then; she has same bike but with much less power, so they do need to be folding. It's ideal for my needs.

Gf is good with stuff like control panel, so she'll get good and hopefully be able to show me the watt meter, as that would be a helpful readout, thanks.
 
I have a similar set up but with a the DPC-18 display. I'm not sure which one the OP has. I can walk him through the settings if he has this one. It only takes about 20 seconds.
I can set it for 3, 5 or 9 PAS, no programming needed. I use the 9 levels now but back it down to #3 (out of 9) most days so I am always pedal assisting. If I go to 5 (out of 9) then I'm doing 28 mph so pedaling is hardly worth it. A 9 out of 9 I'm doing 36 mph so I just let it do it's thing and enjoy.
By not programming the BBSxx to your needs you are abandoning the primary advantages of these motors.
As stated earlier... For a bike used for exercise you should be able to put in effort at all PAS settings. The way mine is programmed using all 9 it helps me maintain different cadences for varying situations. And by using all 9 PAS the changes between each are smaller and transitions between smoother.
I use the first 2 to navigate tight and/or hilly-bumby paths with help and cut out between 5-10mph in the lower gears typically used in these situations.
3-7 for most other situations where I can pretty much do the work on the flats but the motor feathers in assistance proportionally to any resistance encountered such as changing elevation or wind.
8 still allow for me to pitch in but I'm really pumping and 9 is for ghost pedaling but mainly to facilitate full power/speed with the throttle.
Don't think of PAS settings in terms of MPH... but what cadence do you want to maintain. After all the input sensor used on these units is called a Cadence Sensor.
Not saying that my way is the only way... But the stock programming on these units is horrific and after making adjustments it really is a thing of beauty.
Then add that programming is done so easily and that doing so adds efficiency and extends battery life ...there really is no reason not to.
 
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