Technical barrel compression

[andreas]

Hi. I wonder what barrel compression you consider good on a rotax max evo.
I have google it and just find a few discussions about it, talking around 150 psi, but honestly I haven´t find very much info about it.
But 150psi sounds low to me?
We lack bottom end power and are slower than usual out of corners. PV works fine and also tried different carbs aswell.
Thanks
Andreas

 

[Adam]

Hi. I wonder what barrel compression you consider good on a rotax max evo.
I have google it and just find a few discussions about it, talking around 150 psi, but honestly I haven´t find very much info about it.
But 150psi sounds low to me?
We lack bottom end power and are slower than usual out of corners. PV works fine and also tried different carbs aswell.
Thanks
Andreas

I personally have no clue. But worth taking to an engine builder and get them to check it for you, maybe dyno it if needed.

How many hours on it?

 

[andreas]

It´s getting a rebuild at the moment. Only 10h, and compression turned out to be very good, reeds are fine to. I suspect an air leak, the engine has been on a shelf for five years. First few sessions was perfect, but all of a sudden I lost some power.
Tried another short block to rule out problems with carb, electronics, exhaust etc.
So for now I can´t think of anything else but the case leaking somewhere.