Upgrading to a Baserunner with CA3, feasibility questions

[ampflp]

We’re planning to add a kit to my bike (1997 Gary Fisher).
We are evaluating the Baserunner kit - including Baserunner_Z9, CA3, SX1 motor & eRider bottom bracket for the torque sensor.

I have a few questions -

Is there a ‘walk mode’? On my existing e-bike I hold down the ‘-‘ button and can walk with the bike up a steep hill at about 2-3 mph. I haven’t been able to find out from the CA3 docs whether this is available.

Can I attach an existing ‘Basic mode PAS’ magnetic PAS, installed on the left-side crank, to the CA3? I see an input port for a PAS but don’t know the wiring requirements for it. Basic mode as described in the website: “With a basic PAS sensor, the control electronics only knows how fast you are spinning the cranks, but it does not know how much force you are actually applying. Usually these systems produce a set amount of power whenever you are pedaling, although more sophisticated schemes will also vary the assist in some capacity with the cadence too.”

Will this give me the ability to switch between two different mode presets, one that uses the new eRider torque, the other would use the Basic PAS (also fed into the CA3)? - and maybe a third preset for 'walk mode' if needed?

Advice welcome!

 

[amberwolf]

Is there a ‘walk mode’? On my existing e-bike I hold down the ‘-‘ button and can walk with the bike up a steep hill at about 2-3 mph. I haven’t been able to find out from the CA3 docs whether this is available.

Nothing built in, but all you have to do is add a button on the bars that provides the right voltage to the throttle input (can be paralleled with the existing throttle if you have one) to cause it to have a certain amount of torque (since the BR is torque-modulating, rather than speed).

If you need a certain speed, then you can create a preset in the CA with a 3mph (or whatever) speed limit, and switch to that when not using the function on a slope sufficient to slow it down to that speed with the torque you are applying with the button.

These don't get you an actual walk mode for a specific speed that applies however much power is needed to maintain that, but can be used to emulate it well enough for many situations.

Can I attach an existing ‘Basic mode PAS’ magnetic PAS, installed on the left-side crank, to the CA3? I see an input port for a PAS but don’t know the wiring requirements for it. Basic mode as described in the website: “With a basic PAS sensor, the control electronics only knows how fast you are spinning the cranks, but it does not know how much force you are actually applying. Usually these systems produce a set amount of power whenever you are pedaling, although more sophisticated schemes will also vary the assist in some capacity with the cadence too.”

You could do it, but the Erider (and all the other BB TS sensors I can think of) already has a cadence sensor built in. So to do it you'd have to disconnect the Erider whenever using the cadence-only sensor.

It would be easier to use the Erider's cadence sensor without it's TS by making a preset that ignores the TS. (I use a TDCM this way on SB Cruiser because at the time I did that the CA didn't use the TS the way I wanted to, though I think it does for the last few firmware versions).


BTW, the way the website quote describes it isn't quite accurate for the CA's PAS modes. It's like that when using cadence PAS on typical controllers, but the CA does it in the "more sophisticated" way (there might be a way to force the CA to not vary throttle with cadence, but I can't imagine why anyone would ever want that--I still don't see why there are virtually (actually?) zero controllers out there that vary assist with cadence, but instead just do full on or off of whatever assist level they're set to, if you are or are not pedalling).

 

[ampflp]

Nothing built in, but all you have to do is add a button on the bars that provides the right voltage to the throttle input (can be paralleled with the existing throttle if you have one) to cause it to have a certain amount of torque (since the BR is torque-modulating, rather than speed).

If you need a certain speed, then you can create a preset in the CA with a 3mph (or whatever) speed limit, and switch to that when not using the function on a slope sufficient to slow it down to that speed with the torque you are applying with the button.

These don't get you an actual walk mode for a specific speed that applies however much power is needed to maintain that, but can be used to emulate it well enough for many situations.




You could do it, but the Erider (and all the other BB TS sensors I can think of) already has a cadence sensor built in. So to do it you'd have to disconnect the Erider whenever using the cadence-only sensor.

It would be easier to use the Erider's cadence sensor without it's TS by making a preset that ignores the TS. (I use a TDCM this way on SB Cruiser because at the time I did that the CA didn't use the TS the way I wanted to, though I think it does for the last few firmware versions).


BTW, the way the website quote describes it isn't quite accurate for the CA's PAS modes. It's like that when using cadence PAS on typical controllers, but the CA does it in the "more sophisticated" way (there might be a way to force the CA to not vary throttle with cadence, but I can't imagine why anyone would ever want that--I still don't see why there are virtually (actually?) zero controllers out there that vary assist with cadence, but instead just do full on or off of whatever assist level they're set to, if you are or are not pedalling).

Thanks for your detailed response. Most days i can put some effort into pedaling, but there are days that I want to bike but am limited to just turning the pedals without adding any stress.

 

[amberwolf]

Most days i can put some effort into pedaling, but there are days that I want to bike but am limited to just turning the pedals without adding any stress.

I have the opposite problem.

 

[lnanek]

There's a cruise control function you can enable. So you could use a preset to limit the top speed, then just hold the throttle down a couple seconds to get into cruise, and let go. Almost like hitting a button.

 

[E-HP]

For walk mode, just thinking out loud, there may be a way to use the modes, plus the MxNoPdlSpd limit setting under Speed Limits. If it works as described, you could just set it to a custom mode, that has MxNoPdlSpd = 3, and use the throttle.

 

[E-HP]

There's a cruise control function you can enable. So you could use a preset to limit the top speed, then just hold the throttle down a couple seconds to get into cruise, and let go. Almost like hitting a button.

That kludge just solved some the issues I have with the CA (auto)cruise function. I don't want to worry about cruise kicking in unintentionally, so to solve for that, I set a long hold time, but then I have to hold the speed/throttle steady longer when I want to use it, which is a pain, and hard to set accurately.
Your idea of using the speed limit in order to set the cruise speed is great. My thought is to use my analog CA input to set max speed to the cruise speed and the hold time to 8 seconds, so when I want it to use it, I just set the max (cruise) speed and just twist the throttle for 8 seconds, then let go. After it's set, I could just set the speed back to max.