Sam ,You need clarification before you pronounce information as incorrect.
What I said was carefully worded it was TRUE . I said... in SOME.. cases exceeding ..MANY... (as in NOT ALL).
The point being the old wive's tale of halving everything is FAR from true. The (YS 91 Does put out more power than SOME two strokes. I never said it was the MOST POWERFUL 91.
And putting usable power at usable speeds are what 4 stroke do well.
Yes in many cases four strokes are competitive size for size with 2 strokes. Also in many cases they fly better too.
Please NOTE , "MANY" is not an absolute ,as in "ALL"
The amount of development work done on model aviation 2 strokes in the last 60 years dwarfs the work done on 4 strokes since they started getting serious attention about 20 years ago.
The latest developments are starting to pay off and we all win.
Maybe we can save a few fields in the process.
As Hobbs said his aged Merco 50 still puts out a very respectable 8000 rpm on a 12-6 . The YS 53 puts out 10,000 rpm under the same conditions. I know this is best to average comparison . It does demonstrate how much the gap has closed .
Put that 3 horse Jett on an Aeroworks Edge and you will be making my point. The Jett's 3+ Horsepower won't fly it near as well as a 2.5 Horsepower Saito 100. Iam referring to the HORSEPOWER here forget the displacement.
By the way how much does 3 HP cost in a Jett package?
I have already said there are applications where one is better suited than the other.
It is also true the percentage of planes piston powered,running four strokes is growing all the time
Longevity is an issue I have never weighed in on. I haven't worn one out yet so it's not an issue with me. I do know in competition motorcycles 2 strokes get rebuilt at least twice as often as their 4 stroke counterpart.
Your ASSUMPTION a JETT will outlast ANY four stroke ????. That IS an opinion /ASSUMPTION and a real stretch as well
As to question of stroke or cycle , The proper term is 2 stroke cycle or 4 stroke cycle . Referring to the number of strokes to complete a full power cycle. The common vernacular uses one or the other interchangeably if not accurately.