I finally got to go out and ride for a day with my new pumper carb. It is better than my first impression. Here's the thread for that: http://www.thumpertalk.com/forum/showthread.php?t=593672 It was really easy to pull up wheelies over any obstacles, a lot quicker to respond to the throttle with the pumper. I had been trying to tune out some popping on decel and went with larger jetting 132.5/17.5. That proved to be too rich. It was loading up pretty bad on downhill sections and was really hard to start hot. At lunch, I jetted back to 130/15 and it was much better. But it may still be just a tad rich. I may need to do some more fine tuning on the fuel screw. With the 17.5 and the 15 pilot, I was still getting constant popping coming down hill off the throttle. I just can't seem to tune that out. My stock carb is about as perfect as I can get it, near instant throttle response, great mid and top end, and no popping coming down hill. Starting iwith the stocker is quite the drill though. Anyway, I'm going to be keeping the pumper, I really like it and the super quick wheelies it pulls up. Mid and top end seem the same as the stock carb. But with a 2 kick cold starting of the Mikuni, it is definitely worth it.