Topic: How does a prop valve work?

[6099]

Ok, how does it control brake bias betrween front and rear? Looks like the fluid don't mix cause in the reervoir, the rear brake fluid is murky and front fluid is crystal on mine currently.

Reason I'm asking, gonna put in a line lock and don't know if I should put it before or after the proportioning valve. Instructions doesn't say and neither does the vendor's site (Jamar).

tq.

[yellowta]

I think it has something to do with the size of the opening in the valve. As in the smaller the opening going to the brake lines, the less fluid gets pumped out. It's the only idea that makes sense to me since the valve has no moving parts! :wink:   The adjustable ones must control the size of the opening thus regulating how much fluid you can pump to the front, or to the rear. If they were, the same size, then the clamping force would thus be the same front and rear. It's better to have the front do most of the braking on road so that there is less chance of the rear tires locking up and swinging around on wet roads, especially in turns. Off road, it seems like the rear would be the better to lock up in most situations... but I really haven't given it much thought!

[Jeffy]

You want the line lock as close to the brake(s) as possible usually.

Not to mention it would be easier to mount it after the proportioning valve since it hangs under the res.

[6099]

Whoops too late, got a diagram from here:

http://www.motorsportsdigest.com/tech/install2.htm

Most sites and pictures on the net says to mount it in between prop valve and brake pump. (Whyt this is so I still don't know!)

Anyhow, I went and made csutom rubber lines for that. No need to bend and flare any hard lines!

And yeah that makes sense about the different sizes of trhe valves.

Thx.