I think someone mistook cost for value.

Two strokes generally run higher Rpm for a given Hp rating
..hey now, this one can successfully run at 0RPM! granted.. it's over 10 liters and puts out just 45 hp! (though I imagine the ft/lbs are something like 1,000 probably)

 
I've heard it said by some that two strokes can be as reliable as four strokes. I flew many hours in front of (pusher) and behind two strokes and had relatively few problems. But they tend to be a bit finicky and in my personal experience the reliability compared to a four stroke just isn't there.

They can be reliable. It all depends on how aggressive the engine design is. I own several 2 stroke Lawn Boys (yes, I’m a hoarder) and that is all I’ve ever mowed with. They are very reliable, but they don’t make a ton of power and are ported very conservatively. I also have owned numerous snowmobiles, 2 stroke motorcycles, etc. They become more needy and require a knowledgeable operator and mechanic to live a long life the more radical they get.

It is my opinion that the problem that plagues the ultralight engines is that the designers are getting greedy and wanting a high power to weight ratio. Engine durability suffers as a result.
 
I think a modern 2 stroke could be reliable. They still can’t make oil injection that last very long but KTM with their fuel injection and electric start has it pretty well dialed.
 
I think a modern 2 stroke could be reliable. They still can’t make oil injection that last very long but KTM with their fuel injection and electric start has it pretty well dialed.

Oil injection, how fancy. My dad just handed the pump jockey a quart of oil and said put this in with the gas.
 
I flew two stroke ultralight and sport planes for a number of years. Got pretty good at "dead stick" landings.

I've heard it said by some that two strokes can be as reliable as four strokes. I flew many hours in front of (pusher) and behind two strokes and had relatively few problems. But they tend to be a bit finicky and in my personal experience the reliability compared to a four stroke just isn't there.

Maybe I should go find my flame suit now ... :popcorn:

I had a very early weight shift ultralight that was essentially a powered hang glider. I never was comfortable flying it, even though I had a couple of hundred hours of soaring time in the hang glider. The addition of fifty pounds of weight and the resultant increase in approach speeds (and crash speeds as well) didn't sit well with me.

I was working in Austin for a few months, and found a grass strip NE of town where I could fly from. The approach was over a road, and utility lines with the red balls on them too. One day as I was coming in to land, I added some power to decrease my rate of descent, and the engine stumbled badly. This was just as I was nearing the utility lines.

I was carrying enough speed to pop over the lines, and landed without incident. But once on the ground, I thought a bit about that two stroke engine and how much I enjoyed living. I never flew an ultralight again.
 
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