I also elected to place an OS 120 FS on my STA-M. I have yet to fly it but I am sure after reading these comments I will enjoy it.

As far as the engine goes one other thing needs taken into consideration and that is the fuel tank location, I understand everyone has to use a pump so as not to flood the carb due to tank placement.

As far as the 120 muffler configuration here is a nice tip that will save those extra $$ on that flex pipe. Here is what I did. I took the original 45 degree header and placed it in a vise. I then cut the threaded area just behind the pipe its self with a hack saw. I then placed the 90 degree header on the engine and used the piece that I cut as a nipple to join the muffler to the header, which came out perfect, also saving some weight up front. The locking nut was left centered on the custom made nipple so as to tighten muffler to header. I used the high temp RTV gold instead of lock tight as it has a higher locking bond.

I have a question for you 120 FS users. What size fuel tank are you using? and if it be the 16 oz, how much flight time are you getting out of it? Mine is ready for its maiden flight and should maiden this coming weekend.


Thanks
Randy