Brake Bias Valve

[donsrno1]

I have just recently lowered the hybrid and I have noticed that the rears lock up before the fronts so want to adjust the bias valve.

Is it essential to do this for the MOT or will it still pass the MOT even if the rears are locking up before the fronts?

In order to adjust them will it be pretty self explanatory when I look at the bias valve itself? Is it just a case of adjusting it by trial and error till I get the balance right?

Cheers.

[donsrno1]

Just had a quick look under the car and I can see what looks like the obvious nut you turn to adjust it - but am I right in thinking I should be loosening the nut?

[Lunner]

Yeah, i'd do it a little at a time till the rears stop locking up, best to do it when going down a hill, as even less weight on the arse end then

[donsrno1]

kl, will give it a try. Do you know if it will fail the MOT if the front to rear braking ratio isn't correct if you know what I mean? I know they compare each side of the car to make sure its not uneven but I'm not sure about front/rear.

[Lunner]

If its not enough then the rears won't pass the test when they test them, but should be fine, can always get under the car and adjust the bias valve to pass.....just don't go mad when you adjust it

[donsrno1]

ok, just so that I have a rough idea of how much to adjust it - I lowered it about 50mm, should I be looking at a couple of turns of the nut or several? Its just I've no idea how sensitive it is to changes.

[Lunner]

Nor me, i'd do it half a turn at a time and go from there

[donsrno1]

Fair enough, that was my original plan but thought I'd see if you had any idea.

[donsrno1]

Just incase it helps anyone in future it took about 2.5 - 3 turns loosening it to get it to a point I was happy with the braking.

Hit a ****ing pothole driving home though which has put a massive bulge in my tyre - absolutely furious as the pot hole has been there for a while now!! :evil: :evil: