Need the help of R3V - Amputee Driving a Clutch

[LJ851]

^Yes, it is.

[Vtec?lol]

With all due respect, your head is up your ass.



No, you are wrong.

You quite possibly could find a motorcycle M/C thats moves enough fluid but it will be anything but "minimal hand effort". A hydraulic master and slave system is just simple leverage and there is no free leverage!

Think about pushing your clutch pedal with your hand, it has to move several inches and is hard to push. Wanna make it easier to push? Now you have to push the lever (pedal) even farther. As a side effect you just lost all your "feel" of the engagement point because it is so broad now.

which is why Motorcycle MC's are made the way they are since there is no free leverage..
Clearly it's not as simple as it's written.

[DaveSmed]

Measure the pressure of each one?

I suppose hydraulics are a bit of a mystery or something, shit.

It's all in the ratios. If you engineer the system so the ratios work out to be similar, your in good shape. Most of the force multiplication in the part of the system you are interested in modifying comes from the leverage of the clutch pedal.

The stock E30 hydraulics barely do anything more than a clutch cable, which is transfer force from one place to another.

How do I come to this conclusion? The diameter of the input cylinder, the clutch master, is 19.05mm according to RealOEM. The diameter of the output cylinder is 20.64mm. Already, you can see that they are close to the same size.

Calculating the area of each cylinder gives us 284.88 sq mm for the master, and 334.42 sq mm for the slave. Dividing those two numbers tells us that we will get 1.1738 times the force out of the slave that we put into the master.

So, if you push with 100lbs of force on the master cyl, you will get 117.38lbs of force at the slave. Not a real impressive multiplication of force in this application. There's also a catch. Say we push on the master and move it 2 cm. The ratio works backwards as far as movement goes, so the slave is only going to move 1.7cm.

The real obstacle then is not only replacing the leverage of the clutch pedal, but keeping in mind that the average person's leg is 4x stronger than their arm, let alone their hand. You will need to add some mechanical advantage somewhere or else it will be a very fatiguing car for you to drive.


Or maybe a magical "hydraulic reducer" is all you need. ;)

[Swanny]

http://www.youtube.com/watch?v=2KtMCX7FfZ0&feature=player_embedded

feet are for bitches

[LJ851]

Dude, Give me $400 and Ill fab you up a hydraulic operated and clutch/shifter.

The master cylinder on sportbikes "twin quad piston brake lever" will easily move enough fluid to engage and dis-engage the clutch slave with minimal hand effort. Zero hand fatigue and one million clutch control.

Lemme know

With all due respect, your head is up your ass.

lol they've told you wrong my friend.

No, you are wrong.

You quite possibly could find a motorcycle M/C thats moves enough fluid but it will be anything but "minimal hand effort". A hydraulic master and slave system is just simple leverage and there is no free leverage!

Think about pushing your clutch pedal with your hand, it has to move several inches and is hard to push. Wanna make it easier to push? Now you have to push the lever (pedal) even farther. As a side effect you just lost all your "feel" of the engagement point because it is so broad now.

[Pantless Spency]

modifications can not be mad to master cylinders, there no way at all dude.

[5Toes]

I guess I need to get my hands on a beefy motorcycle master cylinder and an e30 master and go down to the local hydraulic shop. They can measure the pressure output of each one

[BigTe30]

Dude, Give me $400 and Ill fab you up a hydraulic operated and clutch/shifter.

Parts list:
Any motorcycle shorty brake lever with adjustable travel
brake line
brake hose
a reducer

and that's it.
The master cylinder on sportbikes "twin quad piston brake lever" will easily move enough fluid to engage and dis-engage the clutch slave with minimal hand effort. Zero hand fatigue and one million clutch control.

Lemme know

If you build it they will come

[Wild Ride]

There is a company based in SD that builds mobility kits for the impaired. On the e92 m3 I saw the throttle was operated by a halo that was the same diameter as the steering wheel and rotated with the wheel. If you pulled the halo towards the wheel and away from the dash it would add throttle. Sorry I can't find a link but that may give you an idea.

[homegrone30]

Ive been talking to my Dad about figuring something out. Hes a left leg below the knee amputee. We want to figure out a way that he could drive with his nub and I have a loose nit idea but its just that an idea.

[5Toes]

reducer is to give more hydraulic pressure?

[camshaftgsxr]

Dude, Give me $400 and Ill fab you up a hydraulic operated and clutch/shifter.

Parts list:
Any motorcycle shorty brake lever with adjustable travel
brake line
brake hose
a reducer

and that's it.
The master cylinder on sportbikes "twin quad piston brake lever" will easily move enough fluid to engage and dis-engage the clutch slave with minimal hand effort. Zero hand fatigue and one million clutch control.

Lemme know

this is what i was trying to get at, but much more thought out than my idea lol

[Vtec?lol]

lol they've told you wrong my friend.

[5Toes]

^ I have been told by multiple people that there is not enough pressure from a motorcycle m/c

[Vtec?lol]

Dude, Give me $400 and Ill fab you up a hydraulic operated and clutch/shifter.

Parts list:
Any motorcycle shorty brake lever with adjustable travel
brake line
brake hose
a reducer

and that's it.
The master cylinder on sportbikes "twin quad piston brake lever" will easily move enough fluid to engage and dis-engage the clutch slave with minimal hand effort. Zero hand fatigue and one million clutch control.

Lemme know