Electric clutch

[Don Thuren]

I searched a bunch and came up with some good info, but was there ever a definitive conclusion if we can or can't add an electric clutch?

Seems like an electric clutch would make the Redshift 99% perfect!

Thanks!

 

[Philip]

If you can hack the firmware, you can add anything.

Alternatively, you can add a controller that alters the throttle input based on the clutch lever position.

 

[C5tor]

Perhaps you can describe exactly what the advantages/features you think an electronic (not physical) clutch would give you over the throttle only setup? Neutral coasting maybe? It wouldn’t really help keep the motor in its power band because there isn’t really one. It wouldn’t help you from stalling the bike, cuz you can’t really do that. Anyway, just curious what you’d like it to do.

 

[Philip]

Some people (not me) have a quicker left finger than their right wrist. That is the only reason that I could think of.

A "clutch" could also be used to produce more than 50ph for short bursts. But for us, this would require hacking the firmware of the motor current sensor. That would be helpful in clearing supercross triples and quads.

 

[Don Thuren]

Perhaps you can describe exactly what the advantages/features you think an electronic (not physical) clutch would give you over the throttle only setup? Neutral coasting maybe? It wouldn’t really help keep the motor in its power band because there isn’t really one. It wouldn’t help you from stalling the bike, cuz you can’t really do that. Anyway, just curious what you’d like it to do.

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.

 

[Don Thuren]

The only time other than power kill I mention above, where the power blip would be nice, is slow walking speed quick instant front tire lifts, which the Alta does NOT do well as is.

 

[TCMB371]

I could have definitely benefited from having a "Throttle Tamer" lever on the left bar when i got in hairy situations. When you're leaned way off the back of the bike after an OJ, for example, its was easier to move your finger forward to grab a lever than to roll your throttle hand forward.

 

[Oded]

Basically, a clutch, can prevent a whisky throttle from going horribly wrong.

In gas bikes, hammering the throttle will get you to the max RPM of the gear you're in.
Hammering the throttle on an electric bike will have you flying to rediculous speed in no time.
LHRB can not cope instantly with such torque.

 

[datadog]

Some people (not me) have a quicker left finger than their right wrist. That is the only reason that I could think of.

A "clutch" could also be used to produce more than 50ph for short bursts. But for us, this would require hacking the firmware of the motor current sensor. That would be helpful in clearing supercross triples and quads.

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.

 

[Redwolf]

The paper principle, where things sound reasonable and plausible on paper, but never translate into reality.

Kinda like my bank account, my savings discussions always sound like they will generate a large balance in my savings account, but it just never seems to happen!

 

[privateer703]

I think he is saying that you can get the power you need quicker when popping the clutch on a revved engine vs twisting your wrist, right? I like to think that if I'm in map 4 I can get that wheel up real easy with just a little twist, if I were to practice it.

 

[snydes]

Envisioning this...

 

[Don Thuren]

Maybe we shouldn't even call what I am thinking a "clutch", as that is misleading... As TCMB noted it's just easier to have a left finger modulate throttle sometimes... When the bike is trying to rip itself forward, it's natural to have your right hand add MORE throttle, where the left finger could be modulating/killing that right hand twist...

Here is a ride I did yesterday.... At 11:00 in I was messing around on some rocks and was super afraid the rear tire was going to hook up, and the bike was going to shoot out from under me!

 

[Mark911]

If some of you folks are serious I can design and machine a clutch system. It’d replace the solid secondary gear very similar to a standard ICE clutch (basket, pressure plate, pull rod, lever, possibly a new counter shaft). Probably use only half the plates and stiffer springs to keep the width reasonable (harder pull but you’d only use it when necessary anyway). A wider machined or printed cover would also be required. Lots of machine time for sure. I can do more cost analysis but suspect it’d be around $2500 for everything. If at that price point there’s enough interest I’ll seriously consider investing all the non recurring engineering time and R&D to create a prototype.

 

[VINSANITY]

Hi Mark - I think another thing worth developing is a foot selector that would replace the handlebar mounted push button power settings. With the foot selector you would be able to change maps while riding with much more control - day you on a long straight run go down to map 1 and then up to map 4 at big uphill etc

 

[privateer703]

Hi Mark - I think another thing worth developing is a foot selector that would replace the handlebar mounted push button power settings. With the foot selector you would be able to change maps while riding with much more control - day you on a long straight run go down to map 1 and then up to map 4 at big uphill etc

That is not a bad idea, and it shouldn't be difficult to do. The hard part would be figuring out what signal the switch is sending to the control board, but even that shouldnb't be too difficult. Setting up a lever with some microswitches would be pretty easy.

 

[Don Thuren]

If some of you folks are serious I can design and machine a clutch system. It’d replace the solid secondary gear very similar to a standard ICE clutch (basket, pressure plate, pull rod, lever, possibly a new counter shaft). Probably use only half the plates and stiffer springs to keep the width reasonable (harder pull but you’d only use it when necessary anyway). A wider machined or printed cover would also be required. Lots of machine time for sure. I can do more cost analysis but suspect it’d be around $2500 for everything. If at that price point there’s enough interest I’ll seriously consider investing all the non recurring engineering time and R&D to create a prototype.

Mark being a machinist myself, and not being able to NOT modify things myself, I looked at that too but the conclusions I came up to were...

1. It seems that with the existing design the clutch basket assembly would just have to be WAY too wide/out into your ankle, no matter what?
2. It seems that the big open spot between the battery and counter-shaft(?) was left open there for a possible future clutch upgrade? Would take a redesigned lower frame but looks like the space is there, to put a clutch between the spur gear and chain sprocket?

 

[Matt]

Hi Mark - I think another thing worth developing is a foot selector that would replace the handlebar mounted push button power settings. With the foot selector you would be able to change maps while riding with much more control - day you on a long straight run go down to map 1 and then up to map 4 at big uphill etc

What about a thumb/finger lever similar to a mountain bike. I feel this would be simple and easy to switch between maps. Thumb would be map down and finger would be map up so that when you are breaking you have your finger available to use the LRHB if you have one.

 

[Don Thuren]

I personally don't really think there is much wrong with the map switch now...

 

[Matt]

I personally don't really think there is much wrong with the map switch now...

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.