Electric clutch

[Don Thuren]

I agree pretty much always except when I was doing the 24hr race last year. I was trying to go as fast as I could while also conserving energy and I was switching between map 1 and 3 often. I had a hard time switching fast without mashing more than one of the buttons mostly because bumps and stuff were making it challenging. It wasn't annoying enough for me to make a solution, though if someone else is looking for one the Mountainbike shift levers would make the most sense to me.

Oh that totally makes sense! I have not ridden mine enough to get that tricky with it haha.

 

[VINSANITY]

The mountain bike thumb index shifter would work great - either way - foot shift or thumb shift would be a huge improvement for on the fly changes

 

[C5tor]

Just speaking for myself here. But I specifically bought the Alta because it didn't have a clutch and it didn't have a shifter.

I still consider myself a novice dirt rider, although I've ridden street for 30+ years. And frankly, the simplicity of the whole electric setup is what appealed to me. Not that I'm particularly uncoordinated, but learning to ride on dirt, especially as an old geezer such as myself, is hard enough when transitioning from pavement. And having to worry about shifting, feathering the clutch, stalling the bike on hills in rough terrain, etc., was just too much of a distraction to the learning process. Especially when I was trying to teach my kids to ride at the same time.

I value the simplicity and robustness of the electric powertrain. It lets me concentrate on proper riding form, gripping the bike with my knees, good balance, proper throttle control, vision, traction, etc. With an ICE bike, those items were way down my checklist of things to worry about in any given instant. I was primarily thinking about when to shift, of if I was in the right gear for this corner, or do I have enough momentum to get up this sandy and rock-strewn hill without bogging it, and things like that.

Switching to electric instantly crossed those distracting items off the list, and I could concentrate on riding instead of managing an imprecise internal combustion process and whirling set of gears and springs. I also took one whole hand and foot out of the control-coordination process, which simplified things tremendously. Right hand go, right hand/foot stop. Brain say, "Wheeeee!"

On the Alta, the act of riding was instantly more fun. My confidence in my riding went way up. I tackled trails and obstacles that had made me hesitate on the ICE bike. The whole lack of maintenance and noise thing and the awesome torque were just icing on the electric cake. Now, I'm not saying I don't like the sound of a thumping four-stroke or banging fast shifts down a straight. I still like those things, and I'm perfectly capable of doing those things. But I enjoy the act of riding more than I liked managing an engine.

 

[privateer703]

C5tor, I totally agree with you and am also a novice dirt rider. My reasons for wanting a different map switch is that the existing switch is not robust. The mounting tabs on mine are broke so if I smash the buttons quickly or in a panic I completely rotate the switch housing around my handlebars. Also, while like I like NOT having the clutch. It allows me to focus on balance and power management when tackling more technical stuff. I'm also an experienced street rider and I think it would be a more natural muscle movement to switch the maps with a shifter. I know that at least once I'll pull my left hand brake really hard when going for that shifter though. Did that once on the street after getting the bike inspected, totally forgot there are no gears and locked up my rear brake while kicking my left foot forward. It probably looked pretty hilarious to anyone paying attention. Anyway, I think if the map selector was a foot shifter it would be more natural for me to switch it. I actually have to look at the map selector switch to hit the right button with my thumb, I don't need to look or think about a foot shifter. That switch is the main reason I just keep it in one map.

 

[Don Thuren]

Just speaking for myself here. But I specifically bought the Alta because it didn't have a clutch and it didn't have a shifter.

I still consider myself a novice dirt rider, although I've ridden street for 30+ years. And frankly, the simplicity of the whole electric setup is what appealed to me.

Oh trust me the only reason I'm even bringing up the clutch or power chop lever, is to make something SOOOOO good, just that more close to perfect... Once over 10mph I agree with everyone who says no clutch really needed, but I like to ride in challenging situations and if I ever raced this thing in a closed course enduro like setting, it would suffer in aggressive slow speed riding, compared to a ICE bike with a clutch...

 

[Philip]

What magic principle of physics would increase the maximum output of an electric motor with a lever? I need to know this, I can retire to a private island.

You can get 50hp out of the MXR for about 25 minutes straight. But it is also possible to tweak it to produce 100hp for a few seconds without overheating anything. It would be cool to have an option to have more power for some jumps and for passing.

 

[Philip]

Basically in sketchy, chunky, slow speed varying traction situations, where you are full arm pump and scared of looping the bike out, one left pointer finger on a "power kill" would be very reassuring. Just today I had to try and hop a small lava-rock gap, from a dead stop, and with the tire spinning and being exhausted, I wasn't sure if I could get my wrist to rewind quick enough if/when the tire hooked up.

Would adding a simple throttle kill switch to your LHRB lever work for you and solve all your problems?

 

[Redwolf]

You can get 50hp out of the MXR for about 25 minutes straight. But it is also possible to tweak it to produce 100hp for a few seconds without overheating anything. It would be cool to have an option to have more power for some jumps and for passing.

Turbo button!!!

 

[Philip]

Turbo button!!!

Push-to-pass!

 

[Mark911]

You can get 50hp out of the MXR for about 25 minutes straight. But it is also possible to tweak it to produce 100hp for a few seconds without overheating anything. It would be cool to have an option to have more power for some jumps and for passing.

100hp with tweaks? I love to know what those tweaks are!

 

[Philip]

100hp with tweaks? I love to know what those tweaks are!

The motor current sensor that you showed us?? Or the firmware, if it ever gets cracked.

 

[datadog]

You can get 50hp out of the MXR for about 25 minutes straight. But it is also possible to tweak it to produce 100hp for a few seconds without overheating anything. It would be cool to have an option to have more power for some jumps and for passing.

Really? Where did you hear that?

 

[Philip]

Really? Where did you hear that?

I just made it up. The 504 battery cells should be good for about 150 hp. I am not sure what the limiting factor would be for the rest of the system, other than the heat.

 

[datadog]

I just made it up. The 504 battery cells should be good for about 150 hp. I am not sure what the limiting factor would be for the rest of the system, other than the heat.

It's obvious that you made it up. You post some really dumb shit. It's like a bit for a bad comic.

 

[Redwolf]

This is starting to get entertaining...

 

[Mharris867]

I suggested a shift lever to adjust maps and a clutch (or anti loop out) mechanism in January 2017 immediately after Alta delivered my early adopter bike vin #29. I remember complaining to Kevin Burns and Lewis Glenn that the switch on the handlebar is impossible to adjust in race conditions and was dangerous after I crashed in the whoops (looping out and grabbing for a clutch that was non existent) and inadvertently bumped the map switch down, picked the bike up then came up super short on a triple and thought I broke the battery or something for the rest of the race. I now set the map to 4 and unplug the wire to the buttons for safety. Kevin suggested the hand brake instead of a clutch and showed me how to modify the sight window on the foot brake to not explode ( I saw that this mod has already made it to the forum) but I ended up removing it because my brain could not handle the fact that it was a brake instead of a clutch.
After racing these bikes for a few years I found you don't really want a clutch or a rear hand brake, you want a way to allow the rear tire to freewheel with 0 acceleration and 0 regen from the motor. This could totally be done in software but once again we are waiting for someone to crack the firmware. Something else I have had to learn to get comfortable with is the regen causing the bike to nose down off big jumps when I let off the throttle. People say to just not to completely shut the throttle in the air but those people are probably not trying to go as fast as they can for 15min at a time with arm pump. A lever to allow the tire to freewheel would fix this and the loop out issue.

 

[Oded]

The closest I got to 0 regen is by using the SM (supermoto model maps). Maps 1 and 2 are great for the lack of regen, but may not be powerful enough for you (motocross)
Map 4 on the SM is by far the strongest, but the regen is very hard and pronounced.

I'll give these maps a try for the enduro type of riding I do.

 

[Don Thuren]

I suggested a shift lever to adjust maps and a clutch (or anti loop out) mechanism in January 2017 immediately after Alta delivered my early adopter bike vin #29. I remember complaining to Kevin Burns and Lewis Glenn that the switch on the handlebar is impossible to adjust in race conditions and was dangerous after I crashed in the whoops (looping out and grabbing for a clutch that was non existent) and inadvertently bumped the map switch down, picked the bike up then came up super short on a triple and thought I broke the battery or something for the rest of the race. I now set the map to 4 and unplug the wire to the buttons for safety. Kevin suggested the hand brake instead of a clutch and showed me how to modify the sight window on the foot brake to not explode ( I saw that this mod has already made it to the forum) but I ended up removing it because my brain could not handle the fact that it was a brake instead of a clutch.
After racing these bikes for a few years I found you don't really want a clutch or a rear hand brake, you want a way to allow the rear tire to freewheel with 0 acceleration and 0 regen from the motor. This could totally be done in software but once again we are waiting for someone to crack the firmware. Something else I have had to learn to get comfortable with is the regen causing the bike to nose down off big jumps when I let off the throttle. People say to just not to completely shut the throttle in the air but those people are probably not trying to go as fast as they can for 15min at a time with arm pump. A lever to allow the tire to freewheel would fix this and the loop out issue.

Anti loop-out I like that!

On a motocross track I don't think the anti-loop/power chop lever would be a HUGE deal, but trail riding/enduro type stuff I think it would be a game changer....

So to move forward with this, has anyone ever looked at the signal coming out of the throttle assembly? If it's just voltage or resistance it seem like that signal could be interrupted by a similar system/control, hooked to a clutch lever, between the throttle and the main control???

 

[Mark911]

The throttle circuit has both analog and digital components. However, I'm not sure what you'd accomplish by modifying the signal that a good right hand couldn't do better. The goal of a clutch is to decouple the speed of the motor (crankshaft) with respect to the speed of the countershaft for a myriad of reasons. All the electronic trickery in the world cannot replicate those conditions.

 

[Don Thuren]

The throttle circuit has both analog and digital components. However, I'm not sure what you'd accomplish by modifying the signal that a good right hand couldn't do better. The goal of a clutch is to decouple the speed of the motor (crankshaft) with respect to the speed of the countershaft for a myriad of reasons. All the electronic trickery in the world cannot replicate those conditions.

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...