Changing the controller

[Silverstreak]

I'm new on here as of today. I'm 76 and been riding since my 5th birthday.
My wife's the same age and has been riding a nice off road bike but its starting to hurt her knees. The reason I put the motor kit on mine. (it sucks getting old). I have a 1000 watt motor and a 52volt battery bafang kit. no complaints. I like it a lot.

The little bike we got her has a single speed pedal assist, no gears. she can never figure out the gears anyway. The assist is Full on as soon as you turn the crank. It in fact lurches forward and if you stop pedaling in stays engaged, all on its own, gaining speed for about 2 seconds. Seems dangerous.

Couldn't I change out the controller for an upgrade for better pedal control? All the screen has is a battery charge indicator too.

What issues might I run into doing that? All I'm looking for is a better riding experience for her, where she feels in control of the bike. Part of he reason we bought this bike is because its small ,16" wheels. step through. she's only 5' tall. I had to be careful finding one that would fit her.

Any input would be appropriated.

 

[docw009]

One could probably get used to the lurch. Squeeze brakes lightly to inhibit motor til on a straight stretch where it's OK/safer to gain speed. A 16" wheel can't go that fast. DIsable pedal assist and use only throttle. Nonetheless, no one wants to fall over, I wouldn't stand for it and have swapped controllers when I didn't like the pedal response.

Buy a 13A KT controller plus a LCD3 display. They have great granularity as far as setting the speed and pedal assist is as good as you can get for a cadence system. Probably looking at 100-120 bucks. You can get cheaper controllers/displays and they'll probably suck like what you already have,

Issues? The new controller may not have the same connectors for throttle and pedal assist so you have to figure them out and splice. Existing motor may not have speed sensor, so you'll have to add one to get the KT display to work. Check out the existing motor for a quick disconnect. Hopefully, it's the standard 9 pin plug,

 

[Silverstreak]

Thanks, I’ll start checking that out. How would I turn off pedal assist .

 

[slaphappygamer]

With KT controllers, you can have 5 PAS levels. 0-5. 0 will be no PAS. You can have this, or any other PAS level, be the default.

 

[amberwolf]

Thanks, I’ll start checking that out. How would I turn off pedal assist .

Usually just disconnecting the wire between the sensor on the cranks and the controller would do it.


There are few controllers that actually provide a way ot use the pedals to *control* the amount of assist-- virtually all of them only determine if you are or are not pedalling, and then turn on the assist at the full amount of the chosen assist level.


There are some controllers (KT Kunteng, maybe LS Lishui) that have assist levels based on system power instead of system speed, which are a bit more controllable than the ones that just have different speeds for the assist levels. But she'd still have to choose the right assist level for the situation while riding, and/or you'd have to configure it so the right assist level is there at power on.


IIRC the LS Lishui opensource firmware OSF (in a thread here on ES somewhere) that you can flash on specific Lishui controller models/displays can monitor the actual pedal cadence and use that to directly control the motor output (but the actual factory lishui firmware doesn't; it's just on/off like the rest).

The same is probably true of the KT Kunteng OSF.

If budget isn't a concern and you'd rather not mess with flashing firmware and whatnot, you can install the ebikes.ca Cycle Analyst v3 in between the PAS sensor / throttle and your controller's throttle input. Then the CA will read your PAS sensor for how fast the pedals are spinning, and generate a throttle output to your controller to directly operate it via the pedals.

The CA is not plug and play; you have to setup every thing in every menu to be sure it is correclty configured for your system and usage. It's not difficult but it can be a bit tedious, and it may require some experimentation with settings to get it to operate just the way you like it.

However, it works well for this once you have that done. I use it to operate my SB Cruiser trike via the pedals; it's my everyday transport.