Toying with the idea of electric clutch operation on motorcycle

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My mother has a 1985 honda rebel. She is a small woman with small hands and arthritis. While i think the clutch is relatively easy to pull i have larger and stronger hands. Her issue is her fingers cant really reach all the way to the clutch handle and then squeeze it. I thought about making the arm on the clutch lever on the case longer and introducing one of those easy pull clutch systems from moose racing. The issue is still her fingers have a tough time reaching the clutch handle. She just wants to enjoy the bike. She can shift the transmission with her foot fine. I was thinking why can i just put some type of 12v servo or linear actuator on the case to actuate the clutch lever and then i can have some sort of voltage regulator on the clutch handle connected to maybe an arduino to control the clutch actuation. Then she could reach the clutch lever and not have to worry with her hand fatiguing. Is there some type of linear actuator or other electrical device im overlooking that may work for this?
 
I imagine if you added a button to the lever that pulled a trunk release solenoid, that pulled on the actual clutch lever, that could do the quick declutching part. Once she has it in her grip, I bet she could let off the button and release the lever under her control. She could also "quick shift" between gears just using the button, only using the lever for starting out where granular levels of engagement are important.

Alternatively maybe you could rig a left hand twist throttle but only about half a hand width, like a grip-shift on a mountain bike. You'll want some outboard stationary grip to hold onto, so she doesn't accidentally mess with the clutch going over bumps or other transients. A fault with this plan is that clutch springs are much stiffer than throttle ones, and it might be some bizzare muscle coordination running both the throttle and clutch at the same time.
 
The Moose racing unit won't do what you want. There is a way to use a spring to "assist" a clutch pull, using a bell crank, but it has to go over center at full lever release. So the initial pull is the same as it's always been. Not sure how this one works:


But to answer your question, I'm not aware of any "fly by wire" system that is commercially available for this. You could make one, given enough time and effort. It is a simple concept, but requires some robust parts.

Think about the spring idea for a bit, if you had a conventional spring with hooks, at full lever extension the spring would be pulling straight against the bearing and not pulling the lever, but as soon as the lever is pulled inward a bit, the spring's force assists the lever. Systems like this have been used on Harley bikes for years.
 
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Wouldnt she be in the same boat for the front brake? May be time for a change to a mid sized scooter if she wants to continue riding. Or look into one of the auto type clutches if you could find something that would fit.

Paco
 
Or an adjustable clutch lever that could be adjusted bringing the clutch lever closer to the bar. Could do the same for the front brake.

Paco
 
I'm assuming its a 250 Rebel (i think they did make larger one at one point)

My bride has similar issues very small arthritic hands. I don't recall her having many issues with her rebel and i thought hers had adjustable levers.

Her Harley i had to replace the levers with adjustable and set them as close to the bar as they would go - that requires careful (and out of spec) clutch adjustment but it works..

My first suggestion would be to put adjustable levers on it if it doesn't have them.

Next idea would be to call Rekluse and see if they could help ...
 
Wonder if Rekluse makes an auto clutch that would fit it? They make clutches that will fit a CR 250 R going back to 1987, so there's a chance...
 
Maybe a little addition. I suffer lightly from tendonitis from time to time.
Of course, i must fell in Love with a 1989 GSXR 1100 and today with a ZRX 1200. Both Bikes have a very "Manly" clutch wich needs a unneccesary strong pull.

As these are hydraulic clutches, you can not compare them with Cable operated ones, but one little conversion i have done to the clutch lever is maybe also helpfull for cable clutches. I simply removed the brass bushing from the lever and replaced it with tiny ball bearings from R/C cars, glued in place with loctite. This makes the action of the clutch lever much smoother and it eliminates the high force you need to "Break the leaver loose" at very, very beginning, overcoming the initial friction.

The job is easy, cheap and done in minutes. It maybe seems ridicoulos, but you feel the difference after a long trip through Mountains and Valleys. Every little reduction of friction counts when you pull the lever countless times a day.
 

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There are quite a few old Hondamatic starter bikes out there at low prices because there is not much demand for them. You may have to look for a while to find a good one since most of them are 40ish years old now.

This currently registered and running CM400 with only 6000 miles is listed near me for $1200 obo. Just a thought.
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Rekluse or an automatic motorcycle is the best path forward with this problem. I don't know if anyone has asked, but do you think it would be possible to control a clutch operated vehicle in stop and go traffic with an electric actuator? Another scenario may be needing to creep forward to get a better look at an intersection. I fear that an electric actuator would not accommodate the need for precise and small movements and may result in surging/throwing someone into an intersection etc.
Not to poo poo the idea, just want to prevent an injury that might take someone out of the sport.
 
I definitely think it would be possible to do it with a servo and be able to control the friction zone, after all steering throttle, control surfaces and even brakes in some cases are done so on Radio Control models all the time, even fairly large ones.

I think the question is how big and how expensive is a servo with sufficient speed and strength (very in both cases is my guess) and is it weatherproof or do you have to encase it.

I feel the other options are a better start. It also occurred to me it might be possible to remove some of the springs from the clutch... possible and a good idea aren't the same thing all the time though obviously.
 
It also occurred to me it might be possible to remove some of the springs from the clutch... possible and a good idea aren't the same thing all the time though obviously.
Not to bad idea. One could try to remove some springs or simply gradually grind them shorter, maybe worth a try.
When you strictly ride allone without pillow passenger and without luggage afterwards, it could work.
 
When my Son was young and having trouble with the clutch on his Blaster, I changed it over to a hydraulic clutch, that is the ticket.
 
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