I just bought an '06 YZ450F today. It is an impressive machine, but I have my first question re: set-up. I race desert in the amature over 45 age class, so could be considered a slow amature, or faster novice class racer. I weigh 220 lbs., and Race Tech's web site says I should change to heavier spring rates, but only by half a step up from stock. For example, the rear spring is a 5.5 stock, and Race Tech recommends a 5.6; and the front springs are .47, and Race Tech recommends .48 springs. Is that small of a change going to be worth the effort, and the weight gain from changing from the stock titanium rear spring to (I believe) the steel Race Tech spring? Thanks in advance.