I am looking to get back into flying pattern after a few years of being out of it. I like the two strokes vs. the four strokes. Any help on who make the best 60 (most powerful and reliable) size two stroke engine would be greatly appreciated since there are so many choices out there. Thanks Mark

Without doubt the most powerful 60 size engine is the Irvine 72 , it is in a 60 case and runs ultra reliable , search the posts , a dinger of an engine

Thanks obi1 for the reply. Does anyone know about a YS 61 as far as power and reliablity?

The Irvine 72 is a powerhouse. Long break in period, but now runs strong and reliably. Takes my Super Stick 60 straight up and out of sight.

Or just get your hands on a Italian made Supertiger 90. Crankcase size is the same as the 60 and 75, just bored larger. That'll give it the kick you want.




Neo

The OS 91 fx is the same size as a .60. I have one in my intruder 90 pattern plane and it has all the speed and thrust you could ask for running an apc 12x10 at about 11,200 on the ground.

Michael

Webra !!

That is (THE BUG) and it has caught me again!!!!!! Thanks guys for all the wonderful input. It is sliming down my engine choices.

I don't know if they make them anymore but a os 61 rf must have exactly the same power as a 91 or more.

I'm a strong advocate for the YS 61AR. I loved mine before I went to 4 Strokes. Hatori or Bolly carbon pipe, and I always ran 25% nitro, what a fantastic engine, and with the YS pump system you can easily put the fuel tank on the CG.

looks like yove posted in the wrong forum.
I agree the Os 91 fx is the best one to go for.
Luke

also new mvvs 90 in 60 size. this engine swings big props

Something to consider,

In pattern, your optimum fuel tank location is over the CG. This means generally about a 14" length of tank line. Most engines without a pump won't be able to draw fuel that distance easily or reliably. Also, in most Pattern birds (that I would consider a true closer to current pattern plane) the engine is inverted and requires a pipe to run down the belly pipe tunnel. This of course isn't needed, you can always cut a hole out the side of the fuse and create more drag (sarcasm LOL) But in all honesty, I'm a firm believer in that, if you are building a pattern plane, to compete, there is a reason that certain engines are always recommended for the specific purpose of pattern flying. I competed up to the Advanced level with .60 Pattern planes (Meridian's) then moved into a Legend 5 and then an olympian before switching to Jets. A pattern bird flies so true, I can't imagine interupting airflow with a big muffler hanging out the side. Whatever engine you choose, I recommend finding something Pumped and place your fuel tank over the CG. Be sure it's an engine that likes to run inverted (with a pump it really shouldn't be a factor).

I was running 13x12N's on my Y.S. .61's at about 10,200RPM on 25% nitro with a K&B "L" plug.

Jeremy you sold me, those numbers are very impressive and the fuel tank on the CG definately makes since. I will have to check out the YS for my new pattern plane. Thanks

Michael