Well 2slow2matter Will you argue about mft. specs? I looked up a Saito FA50 typical 4 stroke I'd say. Rated HP .85 recommended prop for sport 11x7 to 12x6 I looked up the lowly SK 50 2 stroke for an apple to apple size. Rated HP 1.5 recommended prop for sport 10x8 to 12x5 Now 12x6 is close to 12x5 like I said almost even. Now turn a 9000 rpm 4stroke on a 12x6 and a 11500 2 stroke on a 12x5. Gee what will win the race. A 12x5 turning about 20% faster over a 12x6 about 20% less rpm. Rpm are just a close estimate.

Fastsky you must like those SK80's or couldn't pass up the price.

Why, do you have one??? I haven't had a chance to try it yet. I bought it based on a RCU review of a Kange Moncoupe where they were using that engine and yes I thought I would try it for the price. I also bought Tower HObbies and Tiger Shark engines based on the price. They have been impressive performers. They both had sticking throttle barrel issues so I dealt with those and no problems since! I actully check all me new engines for sticking throttle barrels. If they stick when they are new, they don't get better, they hust eventually jam! I have found a few other brands that stick when new but all of them where easy to fix for smooth running. [8D]

Well, I've just done my own comparitive research, Saito 100 vs. evolution 100, and it seems as though I've been lied to. Guess I bought the bigger prop thing hook line and sinker, and never really checked it out. However, I still really love the sound of the four stroke, and wouldn't trade them for anything. I've never said that you would win any pylon races with one, but man you can't beat em for scale sound (unless you go to a big gasser, of course). Maybe I'll consider a large 2 st for my next project now.....But, I will always own and continue to purchase four strokes as well!

For me the choice is simple:

SQUUUEEEEEeeee vs. put,put,put,put

Thanks for the reply 2slow2matter I like reading these forums . But if I heard it once I've heard it a 1000 times. BIGGER PROP BIGGER PROP MORE POWER MORE POWER and it always turns out to be about a 10 to 20 larger size 4 stroke.

No Fastsky I don't have an SK80 but I saw 3 in your hangar. What do you do on the barrels. Do you just take them out and sand them smooth.

You got it! On these engines, the barrel housings are fine but the barrels need to be smoothed a bit, not bad but a bit. It was really bad on my Tiger Shark 75 engine. In the case of the Tower Hobbies engines, the barrel was fine but the barrel housing had what looked like a bit of slag at the bottom of the barrel housing. I used one of the rubber tipped dremel bits to polish the housing out and they turn smooth as silk now. The throttle barrel on the new ASP engine is like an OS clone, never had to touch it. Very smooth turning out of the box. Can't wait for nicer weather to try them out. [8D]