2013 super8 2t. Stock carb jetted at 86 (slightly lean throughout but perfect WOT) - stock air box, snorkel removed. NAraku standard variator, 7.5 grams. gates belt 2mm slightly longer than stock, Tecnigas q tre exhaust.. The exhaust and variator, with perfect running jet size gets me to 45mph now.... with heavy 7.5 weights the takeoff isnt explosive (like it was when i had 4.5 grams) BUT it allows me to live over 40 mph comfortably, and still have a range of smooth acceleration and power up in the high mph... the 88 main jet makes for a nicer richer mid range, but at WOT it runs rich and gurgle's -- it didnt Wine up like it does with the 86.......88 main jet brought me to 43 ,,, and sounded literally like it was gargling down gas. 86 = fine. Stock clutch completely,, I have torque spring and clutch springs but i dont need them in their yet. the mix screw, idle and throttle cable are all as tight and tuned as possible. I have a 20mm Kymco super 8 Intake manifold, gasket, spacer and a 19mm no name brand 2t carb off ebay.. Im going to see what the bigger stuff can do.. but 45 mph with stock 50cc cylinder and carb and air box.