I recently purchased one of these bikes to ride to work, due to the rising gas prices ( and it is cheaper than my 97´ CBR 1100 XX ). But it desperatly needs the valves done. I´m sure I could probably do it myself, but I don´t dare crack into it without knowing the proper clearances, and any tricks or advise others might offer. If you have any advise please contact me directly at psychocrf50rider@yahoo.com THANKS!!!!! And as a foot note I might ad that this bike has surprised me over and over again! It rides very well, and gets AWESOME gas milage!