Hi, i just got my 02 426. its mostly stock but has the WB e series muffler. i do trail riding so i am looking for good low to mid range power but the guy i got it from did mostly wide open desert riding. this is my first 4 stroke. my question is, what is the deal with the plates on the muffler? what would be a good number of plates for trail riding? i think there is 6 or 7 now but im not with the bike at this time. thanks for any help! oh, also what is a good front and rear sprocket tooth combination for low to mid torque?