ORIGINAL: Oberst
ORIGINAL: David Bathe
It is..(was).
And use an F plug
You use it, I'll use what's recommended by O.S.
I have a 1983 FS- 120 that has all the original parts and it runs as if it was just broken in. Why? Because it wasn't screwed with. I'vee been a Tech and worked for Yamaha, Kawasaki and Suzuki and went to AMI in Sarasota, Florida. I worked for several private small engine repair shops and am NYS Certified.
You can be a backyard mechanic or you can be trained as a real tech. I was trained as a tech. The first rule that is taught is you don't use anything that's not recommended by the manufacture or you can risk damaging your engine. Also all manufacture warrenties become void immediately.
All combustion engines run on the same principle even if they run on different fuels. 2-Strokes engines has no moving parts where as a 4-Stroke does. Some 2-strokes uses reed valves where others don't. Some 4-Strokes has tappet adjusments and some only use buckets and you adjust the valves by using thicker or thinner buckets.
Every 6 months I had to be retrained because the manufacture was always making changes and I always had to have special tools.
So if it's Saito, O.S. or what ever, don't take chances and read the book and only do what the manufacture recommends.
Pete
I would have no issues running the F plug. If one would take the head off a 2 stroke model engine and see the plug clearence you would clearly see the plug would have to reach an additional .100+ to make contact with the piston. What we are most conerned with is heat range. The idea is to match 4 things. Compression ratio, nitro content, plug heat and prop. All these things affect the " ignition timing" for lack of a better term. For the most part the manufacturers have all that sorted out and following the instructions is best for people with limited experience. For those of us who like to tinker there are always alternitives. Some work some won't but thats how we learn right?