I really don't want to be changing the bias valve at this point if I can help it.
I was so close to passing overall efficiency (3% below the limit), that I'm sure just giving the brakes a damn good thrashing and getting them bedded in properly will be enough to get through the test.
Just spoke to my friendly garage across the road from work and he said he'll check it on his MOT rollers for my free of charge
So a drive to work next week with plenty of left foot braking might be in order!
Forgot to mention in my write up yesterday. You NEED a bike helmet with these cars. I set off with just sunglasses on, but had to stop and switch to my helmet a few miles in because I was struggling to breath above 45mph
