I have a 02 400EX and my left front wheel is toed in. I have heard two ways of adjusting. First was to measure the distance between the front discs (front and trail edge) on the rotars and true the numbers up (make them the same). Second tip was to use the spindles and do the same. Which is better?

I have a spare set of tires (for sand) where the left tread is getting severly abused.

 

Never have heard of doing it that way. They repair manual says measure from the center of the tire in the front and back.