Electric clutch


Mark911

Well-known member
Location
Corona Ca
The instant surge of power you can get with a clutch isn't really my main reason for wanting this, and I realize and agree with what you note...

You noting a "good right hand" is probably the best thing you could have said... When you are exhausted and can barely hold on, trying to finish a section of slow speed janky rocks or a super techy hillclimb, your right hand is anything but "good"...

A left finger to pull a power kill lever might just keep you on the bike, instead of it looping out whiskey throttle...

Ok, got it. You're looking to attenuate the throttle under certain conditions, kinda a limp mode, even if the throttle is substantially higher (more open). In this case I'd say a simple resistor switched inline with the analog signal of the throttle would certainly reduce the output signal by whatever percent of the input you select. However, there may be cases where the output falls below the minimum value (range) and I'm not sure how the system would respond. Worse case the entire bike shuts down similar to throttle issues seen in the past. That would not be good. I suspect a dedicated circuit could be designed to prevent this from happening.
 

VINSANITY

Well-known member
Location
Texas
For me more of a mechanical clutch would be preferred - you can feather the clutch mid corner or pull the clutch temporarily then engage the electric motor at full revs to get a quick burst of power over a big jump.

I miss using the clutch in many different ways.

A mechanical clutch probably wouldn’t be able to to stand up to the torque of the electric motor and would burn up quickly I think.

Brammo’s electric dirt bike prototype had a clutch and a multi-speed gearbox so it could be done
 

Don Thuren

Well-known member
Location
Bend, Oregon
Ok, got it. You're looking to attenuate the throttle under certain conditions, kinda a limp mode, even if the throttle is substantially higher (more open). In this case I'd say a simple resistor switched inline with the analog signal of the throttle would certainly reduce the output signal by whatever percent of the input you select. However, there may be cases where the output falls below the minimum value (range) and I'm not sure how the system would respond. Worse case the entire bike shuts down similar to throttle issues seen in the past. That would not be good. I suspect a dedicated circuit could be designed to prevent this from happening.

Yes exactly!!! Design the electronics Mark lets do this!!!

I'm even wondering if the electronic guts could be stuffed inside a standard hydraulic clutch lever assembly master cylinder, with maybe some 3D printed supports that slide in?

Just thinking outloud....
 

Don Thuren

Well-known member
Location
Bend, Oregon
For me more of a mechanical clutch would be preferred - you can feather the clutch mid corner or pull the clutch temporarily then engage the electric motor at full revs to get a quick burst of power over a big jump.

I miss using the clutch in many different ways.

A mechanical clutch probably wouldn’t be able to to stand up to the torque of the electric motor and would burn up quickly I think.

Brammo’s electric dirt bike prototype had a clutch and a multi-speed gearbox so it could be done

If the Alta had a true light pull mechanical clutch it would be a game changer, even more than it is... I do agree with you that the crazy torque would probably mandate a clutch off of a car haha!
 

F451

Well-known member
Location
Seattle
I get reminded that my Alta doesn't have a clutch, or I guess more accurately, does not have a "neutral", every time I try to roll it around the garage, or back paddle on a trail. Betweeen the porky-ness and the driveline drag, I really have to put some effort into it, Lol. I often turn it on and use power setting 1 to move it around, its perfect for loading it into my truck.

Re a clutch, so far I haven't really found the need for it during casual trail riding, have actually been amazed at what the bike can do without one, but I can see where it would come in handy, especially if it could be implemented without a significant weight/complexity penalty.
 

C5tor

Chief Comedic Instigator
Location
San Ramon, CA
I get reminded that my Alta doesn't have a clutch, or I guess more accurately, does not have a "neutral", every time I try to roll it around the garage, or back paddle on a trail. Betweeen the porky-ness and the driveline drag, I really have to put some effort into it, Lol. I often turn it on and use power setting 1 to move it around, its perfect for loading it into my truck.

Re a clutch, so far I haven't really found the need for it during casual trail riding, have actually been amazed at what the bike can do without one, but I can see where it would come in handy, especially if it could be implemented without a significant weight/complexity penalty.

I'll also echo how convenient it is to use bike-power to load the bike and move it around. I've turned quite a few heads at the riding area by simply walking my bike (almost) silently up a ridiculously steep ramp like it was nothing. Makes you look like a superhero sometimes. Hehehe.

I used to have a lot of anxiety about loading my dirt bikes. Timing the sprint, building momentum, and then the awkward leap of faith at the end, hoping you had enough speed to make it to the top... The very thought of it would get me in a cold sweat imagining gruesome images of dropped bikes, broken hips, and all manner of viral YouTube bike-loading-fail videos. But just walking the bike up the ramp under its own power is very gratifying. Just one more reason I love this bike.

I've since switched to a much longer and wider (and overall much safer) ramp, and it is simplicity itself. The ramp is kinda bulky to move around, but it makes loading a carefree experience. Even if I'm tired or hurting, or the ramp is slick and the bike is muddy, using bike-power and a gentle, wide ramp makes life easier. In my youth, I wouldn't have worried about the niceties of loading the bike. I would have picked the damned think up and chucked it in the truck if I had to. But with my advancing age and increasingly unreliable knees, I gotta worry about dumb ass stuff like this now!

I also agree that it would be nice if there were some kind of neutral function. I don't always need regen while riding, and sometimes I just want to coast. The bike IS quite the porker when it is not under power. Pushing it sometimes feels more like parking a hippo than a gazelle.

By the way, here is my new Black Widow ramp: (94" long by 54" wide) Very plush! (Well, as "plush" as a ramp can get, anyway.) Should probably put this under Loading section of the forum.
1581531118680.png
 

Don Thuren

Well-known member
Location
Bend, Oregon
I am confused...
That's called Map 1. Takes a good 2 seconds to get to 75% torque. Do you need slower than that?


Yes! I want the burst of Map 4 to instantly get the tire up, as in jumping over a downed tree, but then I want my left finger to kill the power if/when my right hand can't rewind the throttle...
 

enjoythesilenc

Well-known member
Location
virginia
I would love a tractor mode, Pyndon map or creep button.

Yesterday was beautiful for a trail ride and the inevitable "get stuck on steep slippery hill" scenario unfolds. So there you sit, feet off pegs because you are at a standstill. You have to hold the bike on the incline with the front brake so your throttle control is compromised. You can't really push the bike forward and weight the tire at the same time.

Cracking the throttle doesn't do much because the system wont apply enough power at 0 rpm to move the bike if you have any traction. Since you are pushing the handlebars, the rear wheel finally gets unloaded enough for the motor to rotate and it spools up as traction is broken. Zinggg, Zingggg, Zinggg cries the rear tire as your heartrate climbs.

I want a momentary switch push button that I can push that changes the resolution of the throttle. A linear throttle response from 0 mph to 2 mph at wide open throttle position. My 2 mph figure is just a guess at a number, maybe 15 mph would work as well since the current resolution gives you a speed range from 0 up to 70 mph?

A mechanical clutch would be welcomed as well:ricky:

This isn't really an Alta problem, Dirt Rider complained about this situation in a 2009 review of the newly released Zero X dirtbike. A buddy riding his new Sur Ron yesterday had his tire wailing unproductively many times.

I'm sure I'll figure out how to ride it better but there are other scenarios I wonder about. Stalled with your front tire up against a big log going downhill. Dead end trail with nowhere to turn around. Wheelie pirouette possible?
 

leeo45

Geezer in denial
..... Wheelie pirouette possible?

I have found this maneuver to be quite easy and controllable in Map 1 or 2. Much easier than on my KTM. I make it a slower maneuver than on an ICE bike and rely on the enormous low speed torque to lift the front wheel while weighting the back. Just practice some in the open before you're up against that downhill log. You can practice anywhere since the bike is almost silent.
 

F451

Well-known member
Location
Seattle
I have found this maneuver to be quite easy and controllable in Map 1 or 2. Much easier than on my KTM. I make it a slower maneuver than on an ICE bike and rely on the enormous low speed torque to lift the front wheel while weighting the back. Just practice some in the open before you're up against that downhill log. You can practice anywhere since the bike is almost silent.

We call them pivot turns. I just did one just yesterday when I got jammed up trying to turn around in a tangle in a hole. Put a little too much oomph into it, map 2, bike came up way faster then I expected. Caught me off guard as it started to come back over on me, managed to turn it around facing the right direction, but the bike started coming down on me. Down on our side we both went.

I was so bummed no one was there to video it, would have been hilarious. No damage to man nor beast so it was all good. Took a mini rest in the tangle before I got up and hauled the bike upright. So nice to not have to worry about shutting it off or gas leaking. Just resting there peacefully in the bushes looking at the beautiful blue sky while I caught my breath listening to the wind in the trees and birds chirping, Lol.
 

C5tor

Chief Comedic Instigator
Location
San Ramon, CA
I was just watching a few videos on the Electric Motion Escape. It has a pseudo-clutch setup that is half electric clutch and half regen brake. (I think it also might have a foot brake). The EM Epure Race has a real diaphram clutch for serious trials riding. Anyway, I just thought I'd throw this out into the electric clutch discussion. It seems like an interesting way to implement it.

1589495038982.png
This guy demonstrates the PELS/PRB action during this video:

 

VINSANITY

Well-known member
Location
Texas
That electric clutch is exactly what I would want on the Alta or any electric bike - feather the clutch in the corners, or pop up the front wheel etc

That is awesome to see they have it in production
 

wwmotors

Well-known member
Location
Bavaria Germany
I cannot imagine, that this lever can let the engineproduce so spontaneous power for lifting the front wheel more up than turning the gas to 100%!?!? No advantage for me to see!
 

F451

Well-known member
Location
Seattle
I cannot imagine, that this lever can let the engineproduce so spontaneous power for lifting the front wheel more up than turning the gas to 100%!?!? No advantage for me to see!

I'm with ww on this one. A clutch on a typical ICE engine allows the engine to rev freely, then the clutch allows the power to be transmitted through the gear box to the rear wheel, depending on how much engagement is fed in through the clutch lever, and how hi the engine is reving.

The electric clutch seems to just be an additional "throttle" to control the electric motor. There's no spinning the electric motor up and then engaging the gear box right?

I'm not getting it and don't see what it does differently then the throttle?

I've been wrong on plenty of things before so would love to hear, or better yet see a demonstration

What am I missing here?

And the EM looks like a ball, very high quality. Wish they would produce an enduro style bike.
 

Oded

Well-known member
Location
Israel
Clutch on electric bike is usually important for converted ICE bikes riders, who are used to it, and having a hard time taming the bike with throttle only.

I do see a benefit with a clutch on EV bikes, to tame and control the sudden torque delivered to the ground, in order to prevent rear wheel spin. Still, not entirely necessary.

The EM electric enduro bike is the Escape model. Basically a trial model with larger capacity battery, and a seat. Not a real enduro bike, but still a lot of fun (weighs 78 kg).
 

Motophyllic

Well-known member
Location
NY
I have no problem with trials riding my Alta. I use the LHRB and front brake to push pressure Into the tires. A little throttle while holding the rear brake and or front brake makes certain obstacles and maneuvers work. My only problem with it is the timing of the electric throttle as opposed to an ice bike with a clutch. That takes a lot to get used to and I’m still struggling with it a little. The Alta has plenty of snap, you just have to moderate all of it with the right wrist instead of two hands.
 

Similar threads

Top Bottom