I received and installed a hp kit on my bike today. The expansion chamber and the new carburetor are awesome! I will attempt some photos w/ my camera phone in the next few days. The carb is a 15 mm...stock is 12 I think...it smokes a bit but settles down when warmed up. I went for a short ride to check out it's response to the new additions...WOW!!!! I've got to get some ride time on this setup and make some notes. The exhaust tone is quieter than stock and running down a slight grade the speedometer read 43 mph... it definitely increased the rpm's and top speed. I'll report back with what I find after running this baby in.