RE: US 41 questions
TLROLIFF, I am running two of the US41 engines on giant scale warbirds.. Both are dependable, fine running engines.
I did toss the stock muffler, it is too restrictive, and changed the carb to a Walbro #144..These changes only take a few minutes, and around $50 bucks..It will be fine on the Spacewalker.. NO!! it will not run like a $700.00 alphabet engine, but will give you good service... I use Poulan synthetic at 40:1...pick it up at Lowes...