it is a 25CC 2 cycle motor and I have a few questions i am unable to answer myself.
1st. i plan on building a j-3 cub style aircraft for it completely from scratch. now i will be able to do this without much difficulty, but i need to know how big to build it. i don't plan on doing more than lazily flying it around, and it would be nice if i could put floats and skis on it without it wanting to fall out of the sky.
I usually consider a 25cc engine capable of flying a 12 to 14 pound airplane, which will have about 1,000 sq. in. wing area.
2nd. I want some opinions about whether to leave on the pull start. it would be nice to leave it on and just be able to pull start the airplane, but at the same time i know that is a decent amount of wait at the extreme front of the airplane. I just feel it would be more convienent to have it on there so i don't have to drag around my starter.
I prefer leaving the pull start on the engine. However your pull start is on the prop end of the engine, which is dangerous.
5th. and i know this will create some debate. what kind of prop should i use. i would like to use a 3 blade prop as i have never used one before, but if enough people recommend the slandered 2 i will use that instead. also what kind of pitch should i use.
I would always bench run an engine first to make sure that it can be started and then to determine a satisfactory prop. Start with props in the 16” diameter range and plan on buying many different props. Most blowers turn 8,000 rpm and should turn the prop at least 7,000 rpm.
and lastly. should i try and build a new muffler for it or can I adapt the one that came with it. this is the only part of the motor that i'm iffy about. it was used for several seasons, but this is the only thing showing it's age the rest will clean up nicely.
The original muffler will work. You can always purchase or make another muffler after you are successful.
Bill