Oldman: Dont go buy a YS, your Saito will power this model just fine. I havent gotten my UCD yet, but I just bench ran the Saito 100 - wow, what a great motor. yes, it does seem picky about where the fuel tank is, but if you have the tank center centered to carb, then you may just have the low end needle set too rich. I bench ran it inverted to see if it could be finicky, and it was some, but like I said, if the tank is placed properly, then its just a needle problem, adjust it like the owners manual says and the problem should go away - if not, a pump/regulator will solve the problem for sure, and save you big bucks. My Saito was spinning a 15x8 at 8500 RPM, still set way rich, I'll take that with the full pound of noseweight savings and the lack of tailweight, the ability to put after run oil in the motor, not having to send the thing in for a new diaphragm every other year, not spraying myself with fuel when I pull the wrong plug, not dealing with a really finicky needle vavle, not splitting fuel tanks, not hunting down annoying fuel system leaks that make the motor go WAY lean (read another trip to service department), hoping I wont have to send it back to the shop when i get it back from the shop because it still doesnt run right - again, any day and bet it flys way better than the YS 120. But hey its just me. Dont get me wrong, I'm a big YS fan, I've owned 5 of them, sold 4, still have 1 (and it needs a new diaphragm) , nothing beats the raw power of those motors, but for the UCD, I think I can deal with a half throttle hover instead of a 1/3rd throttle hover....