Under the category of strange but true:

Every year, Charlies Hobbies in Tampa had a huge shipment of balsa... I would go in there and cherry pick the light stuff and go home thinking how great that was. I finally got curious enough to ask Charlie back when he still owned the place "what's with the huge balsa shipment? Surely none of the R/C guys are scratch building THIS much locally? (it was a HUGE shipment)

Charlie just chuckles and replies "You are going to hate my answer..."

I think, how bad can it be, scratch building stuff is great, right?

he goes on "... the local college kids taking one of the art courses have to build a diarama every year as part of their final grade and it uses a ton of balsa".

I just stared at him dumbfounded.  Charlie goes "Told ya you'd hate the answer". LOL! Good ol' Charlie, I do miss him, heh. The new guy who bought the store was into model RC Cars more than anything else, and the change in inventory reflected that. Shame...
Eric

I'm glad I found this (very-very) old post concerning in-flight issues with an OS Max-s 35. I have my first one, a Max-s 30, (totally stock CL engine) on a SIG Banshee and am experiencing the same type of issues. Fox 35 burp type of issue when going inverted, and engine wants to quit on the second loop of an outside.

The original author said he went down to 22% oil on his engine and the in-flight problems went away. So, it sure does sound like the high oil content was the root cause.

I have been running 10% nitro and 28% total oil (50/50) on my Max-s 30 engine. The OS owner's manual for the Max-s 30 I found actually recommends 25% oil. I'll try the lower 25% oil and see how the engine does in the air.

Thanks Air Ministry.   

Round 2 is posted, enjoy!

Cheers,
-Andrey

NIB OS 40 VF for sale.  $190