How is clutch pedal force calculated?
The ratio of the force between the pedal and the master cylinder is the inverse of the motion ratio. In this case, the force applied to the master cylinder is 1/0.258 = 3.86 times the force applied to the pedal. (This calculation ignores minor friction forces in the pedal arm bushes and clevis pin.)
How do I know my pedal ratio?
How is it calculated?
- Measure the distance from the pedal’s pivot point to the center of the pedal pad. This is measurement “A” in the diagram.
- Measure the distance from the pedal’s pivot point to the center of the master cylinder pushrod.
- “A” divided by “B” equals the pedal ratio.
What is the benefit of having a high brake pedal ratio?
Increasing the pedal ratio increases leverage and pedal travel. Conversely, decreasing the ratio yields less leverage and pedal travel along with increased pedal effort.
How to measure and adjust your clutch pedal?
The formula is X/Y=Ratio. For example, your stock clutch pedal is 14 inches long (X), with a pickup point measuring 4 inches from the center of the fulcrum (Y). 14/4=3.5, which is 3.5:1. While this may have worked for the factory manual linkage, it is about half of what it needs to be for a hydraulic set up.
What’s the easiest way to test a clutch?
The self-adjusting clutch is one of the two types of clutch-adjustment testing methods, and it is the easier of the two. With your car engine running and your parking brake engaged, slip one foot beneath the clutch pedal and lift it upward toward you. Then, test it by depressing the pedal and putting your car in gear.
What’s the ratio of Fulcrum to clutch pedal?
The pedal measures 14 inches from the fulcrum to the center of the pedal. The math reveals this is a 2.48:1 ratio, which is ludicrously low. To make this pedal match the 6:1 (which is also the optimum ratio for brake pedals), we drilled a new pickup point.
How much free play do brake and clutch pedals need?
Too little, and it’s difficult to press them and get the brake and clutch systems to engage. Most brake and clutch pedals should have just a little bit of free play, usually about a centimeter, which is less than half an inch.
The formula is X/Y=Ratio. For example, your stock clutch pedal is 14 inches long (X), with a pickup point measuring 4 inches from the center of the fulcrum (Y). 14/4=3.5, which is 3.5:1. While this may have worked for the factory manual linkage, it is about half of what it needs to be for a hydraulic set up.
The self-adjusting clutch is one of the two types of clutch-adjustment testing methods, and it is the easier of the two. With your car engine running and your parking brake engaged, slip one foot beneath the clutch pedal and lift it upward toward you. Then, test it by depressing the pedal and putting your car in gear.
The pedal measures 14 inches from the fulcrum to the center of the pedal. The math reveals this is a 2.48:1 ratio, which is ludicrously low. To make this pedal match the 6:1 (which is also the optimum ratio for brake pedals), we drilled a new pickup point.
Which is the best place to push the clutch pedal?
With a hydraulic system, it is all in the placement of the master cylinder push rod on the clutch pedal. The higher the pickup point is on the pedal (closer to the fulcrum of the lever), the easier it is to push the pedal.