Re: Power clutch - Any motorcycle

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Re: Power clutch - Any motorcycle

The closest thing that I know that you need comes from a company called Rekluse. It is a clutch whose working is similar to what is on any automatic scooter. When the RPM crosses a certain value, the "centrifugal force" pushing outwards is used to increase friction between 2 parts till they rotate together at the same speed. Below that RPM, it automatically disengages.

Ofcourse, a Rekluse clutch will probably not fit any Indian motorcycle, so we are still waiting for that Indian automobile engineer to design something similar.


Onto the DIY route, try measuring the force required for the actuator (based on where you plan to install it). You need an actuator that provides sufficient force to actuate the clutch lever (or the clutch cable directly) and move at a fast enough speed that you would expect the clutch engagement, and travel the necessary distance. Usually, in 12V electrical systems, you get 1 or 2, not all 3.
Pneumatic systems would give you all (that's what industries use). They have the speed, the force and the travel, but not easy to implement on a 2 wheeler.
You would be looking at some sort of 12V tyre filling air compressor to generate the pressure, a tank to store it, 12V pressure regulators, 12V solenoids, actuators and some control electronics.

Re: Power clutch - Any motorcycle

Hi seven.five,

I can understand the reason you want to have a power assisted clutch operation, the best is to go with hydraulic. The concept of using a linear actuator for engaging and disengaging the clutch will work theoretically and practically to an extent, but as per my little knowledge you will have very hard time to get your vehicle moving in first gear as you will not have a smooth engagement of clutch, and additionally you will not have any feel over the clutch lever. The actuator may also put additional load on the battery whenever the clutch lever is pressed.

Regarding the periodic fluid replacement, it will be in the range of 1 to 2 years which is long considering other service that we will be doing for the bike. Do update us if you have taken up the modification of clutch operation either hydraulic or electric

Ram

Re: Power clutch - Any motorcycle

Hi seven.five,

I can understand the reason you want to have a power assisted clutch operation, the best is to go with hydraulic. The concept of using a linear actuator for engaging and disengaging the clutch will work theoretically and practically to an extent, but as per my little knowledge you will have very hard time to get your vehicle moving in first gear as you will not have a smooth engagement of clutch, and additionally you will not have any feel over the clutch lever. The actuator may also put additional load on the battery whenever the clutch lever is pressed.

Regarding the periodic fluid replacement, it will be in the range of 1 to 2 years which is long considering other service that we will be doing for the bike. Do update us if you have taken up the modification of clutch operation either hydraulic or electric

Ram

Re: Power clutch - Any motorcycle

Skipping over the virtues of a hydraulic clutch versus a different option for a second, and mostly looking at the examples you have...

The Clake clutch is just another version of a hydraulic clutch with some added adjustability to confuse things.

The "ergonomic" clutch as you put it, is simply working with the physics behind levers. Your basic mechanical clutch lever is a second order lever. That is the load and force are both on the same side of the fulcrum. If you move the load closer to the fulcrum, the amount of force required to get it to move is cut by the distance that you move the load. If you reduce the distance by half (as Midwest seems to have done based on their pictures) the input force can also be reduced by half - so, less strain on your hands. Of course, you have to make sure that you still have the amount of movement in the clutch cable to fully engage and release the clutch. That is one of the reasons why the manufacturers use the geometry they use - though another big reason is just to maximize efficiency of assembly lines so while one bike might need 1 inch of travel, another that uses the same clutch lever only needs 1/2 inch of travel.

You can play around with your clutch to see what the travel needed is, and then do a mockup with cardboard to see if you can move the cable attachment point closer to the handle pivot. If you can, it is pretty much as simple as drilling a new hole and relocating the clutch cable...then readjusting for the new lengths.



But, the meatier topic of an electronic clutch. You would probably want to look at servos as opposed to actuators. Linear or rotational - dealer's choice. Size and strength are pretty varied, but the servo allows for control of the speed and direction of the drive in a much more refined way then what you would find out of simple actuators (think of RC cars or aircraft - the wheels are turning based off from the input degree, not just a simple on/off function). Choice of hardware though would point me towards other transportation applications, as opposed to stealing parts for a kids car.

The fly-by-wire systems are already found on cars and motorcycles in different applications. For example the throttle system on a lot of bikes now is electronic. Twist the throttle, magic pixies carry a signal from the handlebar to the engine where a servomotor opens the butterfly on the throttle body. That same system can be adapted by an interested party to squeeze a grip and send a different group of pixies down to the transmission to pull the clutch. Whether or not the servomotor used on the fuel side would have the needed torque? Don't know. But, it is already rated for durability, exposure and temperatures found on an operating motorcycle.

And, it provides for very smooth application and release of force - otherwise, your starts and stops would be much worse if your throttle position was on/off.