In the last couple of years we've had balance bars needing to be pinned under SVA, welded under IVA, back to being pinned being ok under IVA, and now pinned with a label warning that adjustment could invalidate approval. Which raises a couple of questions...

- What is the legal position on having an adjustable brake bias setup (e.g.. remote knob on the dash) on a road car?

- If my car was IVAd with a welded bar, am I in breach of Construction and Use regulations if I change it in any way, remote adjustable or not?

Although my brake balance passed IVA, it was in no way optimised - something I'd like to be able to do - provided I'm not likely to fall foul of any future MOTs or random roadside checks etc.

AFAIK it's perfectly (road) legal to have adjustable brake bias.
Just another incoonsistency between LAW/IVA/MOT/DVLA/VOSA

Just because you can do a thing dosn't mean it is good idea.


A dashboard knob introduces a temptation to fiddle, a sudden unexpected lock up due too much rear brake bias is one of the quickest ways to put a car through a hedge backwards.

Stick to an adjusting the balance at the pedals, set it up on well surfaced, smooth clean dry tarmac, err very slightly towards the fronts consistantly locking first --- job done for road use you will never need to adjust it again.

For track use in the wet 1 to 1.5 turns in the wet is all that normally is required.