Variable Regen Throttle

[HadesOmega]

Last year I bought a Sur Ron Light Bee electric dirtbike/moped thingie.  I upgraded the controller to an ASI BAC2000 controller and one of the features is the ability to use a regen throttle.  I've never used a regen throttle before so I wanted to give it a try and after using it for a few months it's the tits!  You're able to precisely control the amount of regen.  I suppose it is similar to the regen button on the Chevy Bolt or if you've heard about the Riperton superbike they removed the rear brakes and installed a regen brake lever instead.   Or like the Kawasaki prototype EV bike has something very similar.  It takes some learning to get used to but it becomes second nature after a while.

One drawback is it heats your battery up fast soooo it'll overheat your battery and you'll loose regen suddenly.  Also if your battery is fully charged and you get on the regen hard it will cut off regen because you'er overcharging the battery.  I think the Energicas do something like this.  One good thing is you don't use your mechanical brakes at all, save on brake pads, or use your mechanical brakes.  It's easier to control than off throttle regen also.  Operating the throttle mostly required 2 hands also because you'll want to hold on to the bar or you'll go flying foward.  I hope electric motorcycle will incorporate something like this in the future. 


Here's some videos I made about it.  Kinda long but I tested it in different conditions.

BAC2000 Sur Ron Light Bee Regen Throttle VLOG


BAC2000 Sur Ron Light Bee Regen Throttle Test H20 Hillclimb + Horseshoe Singletrack


BAC2000 Sur Ron Light Bee Metcalf Trail 3 Variable Regen Test Ride


BAC2000 Sur Ron Light Bee Off Throttle Regen Test on Horseshoe Singletrack


BAC2000 Sur Ron Light Bee Regen Throttle Street Test Part 1


BAC2000 Sur Ron Light Bee Regen Throttle Street Test VLOG Part 2

[siai47]

The old Vectrix scooter had this feature.  I never understood why nobody else used this in the electric motorcycle/scooter world.  I thought at one time I had read or heard that Vectrix (and whomever bought the remains of the company) held a patent on the idea and wouldn't let anybody use it.

The application in the Vectrix worked flawlessly.  At rest, the twist grip was in a neutral position.  Roll the throttle forward and the scooter moved forward.  Roll the throttle backwards and the scooter backed up.  In motion, the same action provided regenerative braking.  In addition, the Vectrix had no foot brake and used two hand brake levers on the handlebars.  This is something that any shiftless bike (Zero should be listening) should have.  Almost never needed to use the rear service brake with the regen.  On my Vectrix, I swapped the brake levers so the left lever was the front brake and the right lever was the rear.  Made it easier to modulate the throttle regen with your right hand and control the front brake with your left.

[HadesOmega]

Yeah I've heard of the Vectrix before pretty cool concept to have.  So simple also, it basically a kind of tuned off throttle regen.  Instead of guessing where the regen point is it has a actual stop and if it rolls in the direction more it activates the regen.  Regen is such a neat tool to play with.  The ability to precisely adjust the regen is awesome.

I hope future motorcycles use this or at least have the option to add it.  Even just a button to boost the regen would be nice. 

[Shinysideup]

It's almost as though engineers knew regen was a cool feature, but they just didn't know how to skillfully integrate its functionality in an ergonomic and intuitive user-friendly way.

I have a Chevy Bolt EV and love the fact that it's truly one-pedal driving. The regen can bring the car to a complete stop and hold it there. There's a paddle on the steering wheel to add more regen, in case I've miscalculated a bit when coming to a stoplight.

I use the friction brakes only when there's a sudden unexpected move on another driver's part.

There's a guy on the Bolt forum that has 90K miles on his car and the front brake pads show almost no wear.

I'd love to have truly variable regen on demand on a bike. I think I'd prefer to roll my throttle grip forward, rather than deal with a separate lever.

[Richard230]

Check this out:  https://patents.google.com/patent/US6724165B2/en

[siai47]

Good find, there you have it.  Too bad the current patent holder doesn't license it to others.  It really worked well.

[HadesOmega]

Interesting throttle, looks kinda complicated.  They mentioned a reverse function I remember when I was tuning the regen on the Light Bee I had it set to 100% regen and the regen was so strong when I rolled off the throttle it locked the rear wheel up and it started rolling backwards.  So I can totally see the regen providing a reverse function.