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On 10/28/2021 at 9:02 AM, dgshannon said:

On the surface, sounds good, when you only think of heading down hills. In practice, throttle closure occurs in too many different situations other than downhill.

With a gas engine, rolling off the throttle is followed by continued flywheel engine inertia. So, the Electric Motion, as it stands, is already a bit of a shock to new riders as rolling off the throttle does not have that same inertia, and forward motion ceases much faster. If you add regenerative braking to the throttle action, that would even be more severe.

Think about heading uphill on a gas engine bike. You always roll off a bit and let flywheel inertia carry you over the crest. With a stock Electric Motion, you quickly learn that you better not do that. Even worse if you tied regen braking to throttle closure.

On a downhill run a gas engine provides engine braking, as the rear wheel tries to drive the engine at a faster RPM than it wants to go. In other situations, the gas engine at is still providing a bit of forward momentum while at idle. That characteristic is what the new "tickover" feature on the 2022 EM is trying to imitate. What you are suggesting is the opposite in that closing the throttle would not only stop producing power altogether, but even start resisting forward motion. I don't think that in the end it would be a desired characteristic.

If regen braking were to be linked to any trigger other than its own separate switch, it might work by linking to the front brake lever. It may be a total bust, but would be an interesting experiment. The same type of front brake switch that triggers a brake light could be used to trigger regen. Sounds plausible that if you want the front brake on you might want the rear wheel to experience regen drag as well.

Alternatively, it might well work if the switch was on the rear brake peddle. If it were setup such that the peddle in its full up position closed the switch and turned off regen, the the very moment you pressed the peddle down (even before starting to engage the rear brake) the regen would kick in. Further pressing down would add the physical brake to the regen.

It seems the FRB when asserted disables the throttle. I guess that makes sense, can't simultaneously use the motor as a generator and a motor. I no longer think having FRB assert with either brake is a good idea. Can't use the brakes and spin up the flywheel.

I am also wondering if the FRB is a good idea at all from a failure mode aspect. If the mechanical switch fails open, no big deal, just lose the ability to assert FRB. If the mechanical switch fails closed then lose the motor. Even at my low level of riding I often am on rock where I would dislike losing the motor. I'm curious if anyone knows if the factory EM FRB switch is a single fail component, or a multiple fail component. Single fail meaning only one component has to fail to inadvertently assert FRB, multiple meaning two or more components have to fail to inadvertently assert FRB. My homebrew switch is single fail and is coming off the bike today. 

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The FRB is a ‘Normally Open’ switch/button.  

 I suppose it could somehow fail close- but I don’t think very likely.  More likely would be wires getting chaffed due to improper routing/covers and shorting across- activating the FRB.

  I use  a very high quality switch (not the EM one) and it has been flawless.  Another great feature is if you have to stop on a really steep hill (either someone stopped ahead, tree down or just mess up) pressing the FRB with also work in reverse. So it acts like a rear brake- pretty effectively at a stop.

  I have it located such that is it highly unlikely I would ever hit the button unless I want to.  (I never have yet)-  it will immediately ‘turn off’ the power and start the regen.  If you hit it by accident with throttle on- then take finger off button, it will immediately give what ever power the throttle is set to.  THAT could be an eye opener.

  But I’ve only done that when fooling around to see how the button reacts and how the bike responds.

I don’t do competitions any more, but I would still use the FRB on a steep downhill, since I can then put my feet where I want, hold the button down  for excellent ‘braking’ and just feed in more front brake if needed, or slip the clutch if I want a bit less.

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On 11/1/2021 at 3:25 PM, lotus54 said:

Another great feature is if you have to stop on a really steep hill (either someone stopped ahead, tree down or just mess up) pressing the FRB with also work in reverse. So it acts like a rear brake- pretty effectively at a stop.

That's a really interesting feature I hadn't even considered. Normally if you stop on a steep uphill with nowhere to get your left foot down, it's really awkward. I've done it so many times. In future I'll use the FRB.

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