Hi Guys. Ok, this is what I have recently been telling people:
IMO, the PAS settings on the BBS02 kits are not bad, so long as users think about them in a certain way. Forget about assist level, IMO, that is not how it should be viewed. The PAS level should be used to set the pedal cadence. Just because it’s set to 9, does not mean it will pull more power (although it likely will of course), but if you pedal fast enough and hard enough to do much of the work, the kit will not provide much power, no matter the level that is selected.
PAS works like a switch on the BBS02. It does not adjust as you pedal faster or slower. When you set the PAS level it fixes the speed and it does not want to rotate at a speed much lower than that, or even accelerate smoothly to that speed. These are the reasons why the PAS settings should be left alone or only slightly adjusted. Most things in the software should be left alone, many people making changes are likely doing more harm than good and could very likely compromise the reliability.
Why do i say this?
1. OK, try this. get up to a certain speed using the PAS, now reduce your pedaling cadence, so all you are doing is spinning the pedals. reduce the pedal cadence very low, or speed it up, so it matches the motor speed. What happens when you change your pedaling cadence? I'll tell you, absolutely nothing changes. The PAS signal works like a switch, it's on or off. I'm not debating if this is right or wrong, I'm just pointing out that this is how it works and that is what you have to work with, when setting the controller up.
2. Pull away from a standstill in a fairly high gear (inappropriately high gear). what do you feel? The controller tends to sort of pulse when being asked to work at a low speed using the PAS function (it can accelerate smoothly from zero on the throttle, so i don't see why it can also do this with the PAS signal, but it can't). It seems to me like the controller when working in PAS mode, just does not seem to be able to function well at a speed significantly below the motor no-load speed. This motor no-load speed is adjusted by changing the PAS speed setting associated with that particular "Assist" level. The standard PAS settings start with a speed of ~40% in PAS assist level 1. Even with 40% speed, it will not pull away smoothly from a standstill in PAS only mode, so what's it gonna be like when you have every PAS level set to 100%?
So what happens when you ignore the above points I've made above (which are quite easy to confirm yourself) and set the speed to 100% for all PAS levels and only step the current up from a low 10 or 20% current in setting 1, up to 100% current in setting 9? What happens is this. That place where the controller doesn't want to be, that point where it pulses, is no longer only seen for a brief time as you get moving from a dead stop, it's now there all the time when you select a low PAS level (with low current ~10-30% combined with 100% speed) and use the kit. If you only ever pedal very fast, you could possibly use the kit set up in this way and it may work well for you, but a large proportion of users will complain it is crap because they don't use their bikes gearing properly and don't want to pedal at 120rpm the whole time. These users will complain it feels terrible, pulses and then breaks in a very short time (whilst they thought they were actually baying the kit in level 1).
Bearing all this in mind, does it now make sense why i say this:
IMO, the PAS settings on the BBS02 kits are not bad, so long as users think about them in a certain way. Forget about assist level, IMO, that is not how it should be viewed. The PAS level should be used to set the pedal cadence. Just because it’s set to 9, does not mean it will pull more power (although it likely will of course), but if you pedal fast enough and hard enough to do much of the work, the kit will not provide much power, no matter the level that is selected.
IMO, the BBS02 works best when the speed and current progressively increase from assist 1 through to 9 (as is done in the standard settings) and you use the PAS level to set your pedaling cadence and forget about it as assist or power level. Do not view it as an assist, it's not. If setting 5 is the right 1 for you, use setting 5, if you want to do more work, pedal faster and you will take the load away from the motor.
The SW changes can only make the best use of the hardware, when combined with using the kit in an appropriate way. You can't change the hardware limitations of the controller by changing a couple of settings, but you can use the software to tweak things to disguise it's shorfalls and hopefully avoid it operating in ways that are likely to blow a fet due to overcurrent. Did i mention the controller seems to have little or no phase current limiting, well it hasn't and the fets are cheap low level things that are easily blown. At least now, they have fitted 9 low quality fets to their 25A controller instead of 6 low quality fets, like the previous version 25A controller.
Bearing all this in mind, can people now understand why I state the below. This SW is really not something that should be out for anyone to use, you can very easily ruin the operation and blow a fet with a few small changes:
The BBS02 controller are very easily damaged with a single bad setting, so for all these guys changing settings, they should be aware they are easily damaged if incorrectly configured and it’s not fair to expect a warranty replacement on controllers, after changes have been made, no matter if those settings seem quite reasonable or not.
Thanks
Paul
