A very Happy New Year folks from a very chilly Charente in S.W.France.

Advice please regarding the expected launch RPM of my 'older ' engines.

I have several older engines , which are usually run on a fuel mix of 25% lube' , usually 18% castor , 7% synthetic with 5% nitro. I am using  MAS 10X6 props' and uniflow R/C plastic tanks. I am also using tongue mufflers.

My 'best/reliable' launch RPM's are as follows :

ENYA 35 [ 5224 ] : Around 9,000.
OS 35S              : Around 8,800.
Fox 35 [ 40th and 50th Anniv'y ]    : Around 8,600. [ With all castor 27% ]

Do these appear about right guys or should I be expecting someting better please ?

Much obliged for any contributions ,

Robin [ ex-pat Brit in the Charente full of ex-pat Brits ]

As said, sounds about right.  I'd suggest you try a handful of different brand props around the size.  Prop makes a lot of difference to how the engine runs and how the airplane flies.  I've been running 11 x 5's on my Fox stunt 35 for a good while now. 

Much obliged for the contributions fellas ,

Thanks ,

Robin.