25hp Kohler on my Walker[roughly 2800 miles]. Long story short sometimes it will run like a champ and other times like its on its last cut. Whether the blades are engaged or not, it has a miss, especially at high rpms[seems higher than what I would consider normal] and when I back it down to half throttle, it seems to almost choke out/just cut off. When the blades are engaged, they obviously do not have the speed to cut well. Going up a slight incline, again, the mower noticeably slows down[rpms,speed and blade speed] This is not constant. I changed the plugs and fuel filter today. Rode around for a minute and it was sputtering and going through the same issues. A couple of minutes later, the rpm,s came up and ran great. Though not at full capacity, I was able to finish. I hope I have described this so that anyone can understand. My neighbor say its the floater in the carb due to the fluctuating rpms and not on the lower side all the time. PLEASE reply with your thoughts. My plan is to rebuild the carb next week.