My friend got one from Bergan.

HI SKYCAM
COULD YOU TELL ME IF THE G231 YOU ARE TALKING IS THE SAME AS THE ONE THAT IS MODIFIED BY BH HANSON AND SOLD BY BERGEN IN HIS OBSERVER.

I really have no idea what they are actually using. The
GP231 is the new G23 with the larger carb. 603 and new port timing with larger cooling fins.

John

Will this new 24.9 cc engine work in a airplane? Is there a photo of one online somewhere? Thanks Captinjohn

I believe that it is a Airplane version and is converted for Heli use.

http://horizon.hobbyshopnow.com/prod...p?prod=ZENE38A

The G231 is not a converted airplane engine, Zenoah is producing a PUH version of the 231. They are still new, and Horizon is the US distributor.

The cylinder/piston design is different as is the carburetor. I have not done any port measurements.

The engine has fairly robust fins and runs about 80-100 degrees cooler than a normal G23. Thats about the same difference found with some of the aftermarket cylinders, so there isn't any reason to install them for cooling purposes.

Its easier to start than the G23 and it runs smoother than the G26 (at least over 10K RPMs). Not sure about actual power, but from some of the tests we've run, it appears to produce more torque than the G23.