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[Kocho]

Does anyone know if the ABS system on '15 and '16 models kicks-in and if it actually can have any effect, if rear wheel traction is lost due to regenerative braking? My guess is, that the ABS might detect the slippage and try to release the brakes, but unless the system is integrated with the motor controller (which I'm guessing it is not), it won't do any good if the loss of traction is mainly due to regenerative braking and not due to friction brakes use...

[BrianTRice@gmail.com]

Yes, it kicks in and has an effect. No, I did not experience a loss of traction. Notably, my braking regen is set at 100%, and I deliberately locked up the rear wheel to test. No, as far as I can tell, you can't lock up the rear wheel with regen braking - surface friction would have to be pretty terrible (ice-ish) to do that.

ABS works by measuring wheel rotational speed, so it seems that it's designed to track that very reliably no matter what other factors were acting on the wheel like regen (or engine braking! this works the same on a gas bike).

No coupling to other systems is required. Unlike, say, traction control, which would require motor controller integration, ABS relies on one direct feedback loop.

[yhafting]

Yes, it kicks in and has an effect. No, I did not experience a loss of traction. Notably, my braking regen is set at 100%, and I deliberately locked up the rear wheel to test. No, as far as I can tell, you can't lock up the rear wheel with regen braking - surface friction would have to be pretty terrible (ice-ish) to do that.

ABS works by measuring wheel rotational speed, so it seems that it's designed to track that very reliably no matter what other factors were acting on the wheel like regen (or engine braking! this works the same on a gas bike).

No coupling to other systems is required. Unlike, say, traction control, which would require motor controller integration, ABS relies on one direct feedback loop.

Do you have any hard evidence / statements from zero that backs up ABS interfering with regen? 

As far as it seems to me, regen is either on or off at speeds above the threshold. At lower speeds regen is definitively off, which always will allow some speed on the back wheel- but this is something inherent to the regen system- not to the ABS. I doubt that the ABS interferes at all with the regen, and although it is possible to design such a feature, wiring the brake system to the engine does induce complexity and thus creating new ways of creating errors. Add to this that the currents induced by regen will diminish at lower speeds, and there will be 0 regen on a wheel that doesnt turn; so you will effectively always have the wheel turning using regen without using ABS.

On slippery (icy/oily/..) road, i'd guess you still could experience loss of traction if the back wheel starts running slower than the front. At least i would not gamble on it not having any effect, although it is not likely to cause problems normally.   

Since our bikes doesn't have a clutch (and mostly to communicate my braking using brake lights), ive deliberately set the regen on coasting low (6%) for my custom setting that i use for my daily commute. I'll use the mode button to gradually increase regen through sport and to eco if i'm going downhill or want to slow down by regen without turning the brake signal on. 
 

[BrianTRice@gmail.com]

I assume you meant to quote the original poster, but I'll clarify just in case.

I'm claiming that ABS only cuts back on hydraulic braking (like any Bosch ABS system) and that regen might contribute to wheel lockup, but the ABS will only act via its wheel position/velocity sensors to detect wheel lockup. ABS only removes brake pad application from a lockup scenario.

[yhafting]

I assume you meant to quote the original poster, but I'll clarify just in case.

I'm claiming that ABS only cuts back on hydraulic braking (like any Bosch ABS system) and that regen might contribute to wheel lockup, but the ABS will only act via its wheel position/velocity sensors to detect wheel lockup. ABS only removes brake pad application from a lockup scenario.

OK. Then we agree. I posted because i felt your post could be interpreted as something else. 

I believe this topic is important since our bikes does not have a clutch system to make the wheel rolling free, and it could be disastrous if someone
acted as if regen never would cause loss of traction.

[MajorMajor]

In rainy conditions it might be advisable to reduce regen if it's normally set to a very high value.
I really wish we had progressive regen instead of on\off.
Has anyone here experienced rear wheel lock during regen during non-optimal traction conditions?

[DPsSRnSD]

In rainy conditions it might be advisable to reduce regen if it's normally set to a very high value.

I use Eco mode when the streets are wet because of the increased regen. I've ridden electric bicycles with the regen set as high as the motor and battery would take and never had a problem in the rain. Regen reduced the amount of hydraulic brakes I had to use, and lessened the chance I'd lock up the rear wheel.

[BrianTRice@gmail.com]

The regen range is limited to prevent wheel lockup - I've had traction problems in oily wet conditions but not because of regen. The benefit of Eco mode there is mainly lower torque ramp-up from the throttle, and on the regen side it helps to slow down a little earlier to give you a larger margin to react with brakes if needed.