Brake Lines and Brake Bias...

[SprintStar]

Originally posted by Richie
Hi,

You're correct about the proportioning valve. But, is the brake-system of a bug x-split? I don't think so. The MC has 3 outlets. 2 are for the front wheels and the other one goes to the rear where it is split for left and right. This way it is split front and rear.
Place your proportioning valve in the line that goes to the rear, so you can change the bias going to the rearwheels.
This is mostly done in racing during wet conditions to prevent rearwheel-lockup.
I wouldn't recommend it for street use unless you can lock your proportioning valve after you found your desired setting after you fitted those huge six-pot calipers front and rear .
Not being able to lock your valve can cause front or rearwheel lock-up when somebody changed the setting of the proportioning valve without you knowing it.
Sorry to be so long but I felt it necessary. A proportioning valve is great to have but can be dangerous as well.

Hope to have helped (a little)
Cheers,
Richard

Hello Richard,

Thanks for replying. I was under the impression that the Bug has a X circuit as I was enquiring about a late 944 master pump and was told that it's set up for front/rear and not X. It is a stepped cylinder, meaning the front and rear chambers are of different sizes. Anywhere we can check and confirm the configuration?

I was also thinking. On my 944 brake setup (I'm currently using the stock Bug master pump), I find the rears a bit lacking. Do you think it's a good diea to put the valve on the front circuit and then I'll be able to "increase" the rear bias by reducing the front? It sounds sensible as the rear calipers are smaller than the fronts.

Of coz if all the calipers are the same size, I gladly accept that the valve should be put on the rear.

Hehe... An extra question : Can I use the bias valve as a line lock? Would sure be cool if I can lock it and do burnouts.

Sprint.