Detune Options for Pedego Motor?

[rpr]

I’m considering a Pedego Element for my wife. Long story short, it would be close to ideal for her but the power delivery is crude. Even in the lowest power assist setting of 1, when you start peddling you feel like you just floored it. I like power, but the power delivery curve on this bike is just terrible (20” wheels with 4” tires).

Most owners of this model seem to like the extreme and abrupt power delivery from a standstill, and they’ll proudly describe it as “torqy”, but it’s tough to control for a small rider with limited capability. More like riding a dirt bike.

So, I’m wondering if this motor can be detuned to reduce the power assist, so it kicks in more gradually. Are there any options out there that could do that? The folks over at EMTB forums thought the experts here might know of some solutions. I searched here but didn’t come up with anything.

I don’t know who makes the motor. I’m assuming Pedego themselves. This is all the info they publish on it on their website.

MOTOR
BLACK 48V BRUSHLESS GEARED REAR HUB MOTOR; 500 WATT NOMINAL POWER RATING; 45NM TORQUE; QUICK DISCONNECT CABLE W/ WATERPROOF CONNECTION

Any thoughts/suggestions?

 

[Eastwood]

It has to do with the controller not the motor. Some controllers have a smooth power curve while other ones are like an on off switch. So the only way to correct this is by changing to a different controller.

 

[amberwolf]

Yeah, unfortunately Pedego (like most other PAS systems) uses assist levels and PAS control mode that works like this:

PAS is on/off, so any pedalling detected turns assist on at full amount of level chosen.

Assist levels are speed limits.

So if assist level 1 is a speed of 10mph, pedalling at all will have the controller do it's best to spin the motor at 10mph. If at level 2 of say, 15mph, then it will try to reach and maintain 15mph with any pedalling at all.


Usually the throttle (if present) on these systems will still control the full range of motor speeds, so a solution for some people is to move (or remove) the PAS sensor magnet ring so that it can't engage PAS at all, and it only works with the throttle. (disconnecting the PAS may give an error on the display that prevents the system from working at all on some of them) As long as the system is not designed such that if it doesn't detect pedalling via the PAS sensor it turns off after a certain amount of time (even though you're using the throttle at that very moment), this is one workaround.


Another workaround, again assuming it doesn't require PAS input to stay on, is to get a Cycle Analyst v3 and connect the PAS sensor and throttle (if any) to the CA's input instead of the controller, and then connect the CA's throttle output to the controller. Then you can setup assist that is proportional to pedalling speed, like I use on my SB Cruiser trike. If desired you can add button controls on the CA to either change to one of three presets (that can change a number of possible parameters including speed limits, which is how I use mine), or a knob or button set (or both!) to alter a single parameter thru a wider range.


Other than those, changing your controller and display out for a KT controller/display (with or without the open-source firmware installed) would give you "torque simulation" PAS instead of "speed control" PAS, so that pedalling gives a certain (non-variable per assist level) amount of "torque" instead of speed, which tends to be more controllable. (there are other settings in it that allow more tuning than the typical speed-based PAS does as well).


But the CAv3 method will give the most bicycle-like experience, because you are directly controlling how much assist you get by how much you pedal, instead of having assist on or off at a specific level all the time regardless of how much you pedal, as long as you are pedalling at all.


[strike]BTW, the pedego I worked on for Cvin a few years ago had a Bafang motor and a Lishui controller with a Kingmeter display, IIRC. There's a thread around here somewhere for it, I think. [/strike]

EDIT: it's a Pedego Latch, with a Dapu motor, and I think it was also a Dapu controller and display (but I don't ahve pics of those in the thread):
https://endless-sphere.com/forums/viewtopic.php?f=30&t=114480

 

[rpr]

Thanks, great explanation. The CAv3 method seems quite a bit more practical than a new controller & display. Terrible display on those units but seems like the Throttle Ramp settings would address my primary concern. Is it a set it once and forget it type of device?

 

[amberwolf]

More or less. At first there will be some tuning of various parameters to get the desired results, but once it's working the way you want it, you just leave it. My settings have been almost unaltered for a few years now, other than some experimental changes to accomodate new hardware on the trike as I play with new (old) stuff to see what happens.

It's not exactly plug-and-play; you do have to set everything up in it, usually even things you aren't using, because so many things interact with each other that if you don't have a known setting in each place to work from, you may not know why it is misbehaving vs what you want it to do.

If you don't like it's size or looks, you don't need the CA itself on your handlebars. It can be anywhere, including in a toolbag or accessory bag, etc. You only need to see the display when setting it up. (not even that if you are using the serial-USB cable from grin and programming it from a computer instead of the onboard menus). If you need to change presets or whatever on it, you can use remote handlebar buttons or knob for that.

One other caveat: you will still need the original display, even if it's not on the handlebars. It has to be there to turn the controller on (well, there is a wiring hack to get around that), and to change the assist level to something that lets the throttle work at full speed, if it doesn't do that at power-on. (the CA cannot talk to the controller to do this, only the original display can).


And...this setup won't work if your controller requires PAS to be working in order for the system to stay "on" and working. (there are slightly complex exceptions to this, but you should assume this system is not one of them until proven otherwise). If your controller requires this, then you'll have to change the controller to be able to do this, or create a circuit that pulses the PAS line just often enough to keep it awake, but not enough to affect it's ride behavior.


My CAv3 settings are posted in the SB Cruiser thread, and probably in the CA3 "beta" thread, in various places, and somewhere in another thread I can't recall what it was about I also posted them for someone else. So you could start from those, altering them to your specific system hardware (like if your battery is different, or you want different presets, how many magnets your PAS sensor magnet ring has, etc; you'd probably turn off the regen stuff as you can't use it with the little geared hub the Pedego probably has).

I actually have a torque sensor BB (TDCM) on the trike, but have not been using the torque sensor part, so it's just the pedal-speed control that can also be implemented on your bike.

You might have to do some rewiring (possibly cutting into your system wiring harness!) to install the CAv3 the way it needs to for your purposes; this is likely to void any warranty your bike might have.

If everything you need to splice into has connectors you can buy mating plugs for, then you can instead just get those plugs (such as on extension cables you can cut in half), and then wire the CA connections to those plugs, and then plug the CA into your system without cutting into your actual bike wiring.

You will need the "SA" model of CAv3, which has a separate current-monitoring shunt to connect the CA to your battery so it can monitor battery current and system power levels, etc., which is useful not only for monitoring battery usage/etc., but also for letting it modify operation based on those things, which can give you even more tuning/control options. It's also easier if you use the CA's own separate wheel speed sensor rather than trying to splice into the one that comes from your motor. It's one more wire and thing to tie down to the bike frame, but it saves enough time and effort that it's worth it...and it also means you can compare the speedo on the CA vs the bike's display for doublechecking functionality of each one if you ever need to.

 

[rpr]

Awesome info, extremely helpful. Thanks so much!