The pic above is a good way to measure width. The way I see it, AMA makes you ride through two horizontal bars that are 50” apart, so width is measured from sidewall to sidewall. I use two cans of brake cleaner to measure width. Take the cans and place them on the ground up against the bottom of the side wall on each side of the quad. Make sure the cans are flat on the ground and just touching the side wall. Push the quad out of the way and take your tape measure and measure between the two cans. I measured my stock 700XX width using this method back when I first got it and I am positive the stock width was just under 48” or so.
I used to run my 450R’s at the max width I could, never paying attention to how wide they were. They never cornered great, but I didn’t think they were that bad. One day I saw a post on a forum from a suspension manufacturer, and he said the rear of your quad should be ¼” to ½” narrower then the front to help with cornering. Went and measured my 450R and found the front was 50” and the rear was almost 51”. Swapped hub spacers around on the rear axle to get the rear width under 50” and took the quad out for a ride. I was amazed at how much better the quad cornered just after that small change. Since then I have always paid attention to widths and always set the rear slightly narrower then the front.
Doug
