Proportion Valves for Brakes

[Morris]

Originally Posted by cycleguy55

Assuming I understand this correctly, a bias bar setup will maintain the same F/R bias throughout the range of braking pressures (Figure B in linked article).


A proportioning valve, OTOH, 'caps' or limits the pressure applied to the rear brakes. IOW, if the pressure bias built in to the braking system with a proportioning valve was 60/40 F/R, that bias would be maintained until the 'kneepoint' of the proportioning valve is reached, at which point the front brake pressures continue to rise with pedal pressure, but rear pressures level off (Figure C in linked article) to prevent rear wheel lock-up.




There's more in this article from StopTech - certainly worth a few minutes to read: Proportioning Valves

Thoughts?

This proves what I was saying....Very good illustration...and shows why we used both to fine tune the response of the chassis in the corners.....but it takes a lot of experience to get to this level......