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racer98
05-07-2008, 09:39 PM
What would be the ammount of weight (lbs.) is required to push in a clutch pedal ? In other words would it be with in this range ? (8-35lbs of force)


working on a clutch set modification. :naughty:

Fries
05-07-2008, 09:50 PM
Get weights and try? Correct me if I'm wrong, but wouldn't it depend on the "stage" of the clutch//unsprung or sprung blah blah?

racer98
05-07-2008, 09:53 PM
Get weights and try? Correct me if I'm wrong, but wouldn't it depend on the "stage" of the clutch//unsprung or sprung blah blah?

ball park figure is what Im after. :bash:

GSXRJJordan
05-07-2008, 09:55 PM
That's a DAMN good question. People generally talk in "multiples" of stock pedal pressure, eg "Clutch A holds xxx ft-lbs, and takes 55% more pressure". I'd say 100% more than (2x) the stock pedal pressure is the upper limit of comfortability, but if the engagement is tricky (like an unsprung 3-puck), you might want to lower that number. So find out what stock is :)

racer98
05-07-2008, 10:03 PM
That's a DAMN good question. People generally talk in "multiples" of stock pedal pressure, eg "Clutch A holds xxx ft-lbs, and takes 55% more pressure". I'd say 100% more than (2x) the stock pedal pressure is the upper limit of comfortability, but if the engagement is tricky (like an unsprung 3-puck), you might want to lower that number. So find out what stock is :)


Im guessing 10lbs ? - 15lbs. :axe:

Sileighty_85
05-07-2008, 10:04 PM
well i pushed on my clutch and tried to imitate on a scale and it felt around the rage of 40-60 lbs on a stock clutch

racer98
05-07-2008, 10:04 PM
hmm.....................

racer98
05-07-2008, 10:14 PM
another question would be is, How much time is between shifts.

From inital pedal reaction from a standing stop and between shifts.

2jzs14
05-07-2008, 10:16 PM
they have a tool that measures pedal force. I'll see if i can get my buddy's and try it

racer98
05-07-2008, 10:36 PM
Thanks, looking at ways to build something really intresting right now, this is why I need this info.

crzycav86
05-07-2008, 10:48 PM
The ONLY thing that affects required pedal force is the stiffness of the springs on the pressure plate. that's the only thing.

If you know the stiffness of the pressure plate, you can calculate the equivalent stiffness at the pedal using:

pressure plate stiffness,
the leverage at the TOB fork,
the surface area of the slave cylinder piston,
the surface area of the master cylinder piston,
and finally the leverage at the clutch pedal.

it would be an interesting high school physics problem if anyone has the parts in front of them to take measurements. Unfortunately, I don't know if companies disclose the spring rate of their pressure plates.

yudalicious
05-08-2008, 03:48 AM
try using a small hanging scale. hook to the back of the pedal close to the actual pedal area and pull into the firewall and see how much it takes for the pedal to actually move from rest. might have enough space to do it. crude but it might work.