I took a kaw h2 750 and polished the entire intate ports, exhaust, the entire inside ot the case to a mirror finish and the preformance increase was very very noticable. I understand that the fuel needs to be susspended in the air for complete combustion but in these small motors air flow is so fast and short that gravity has little effect. try it and you will get a faster motor.

(Snipped from post #18)

One thing nobody has commented on, is warranty responsibility.
A little while ago there was a thread here where an engine lost the screw that holds the choke in place, the screw was digested by the engine, with grim results. Increadibly enough, the supplier of the engine refused warranty responsibility, because the engine owner at one stage had taken the rear-mounted carburator off the engine, in order to install this in the plane. The fact that the choke screw had not been taken off in this process, seemed irrelevant to the supplier. What was important in his view, was that the engine had been "modified". (Increadibly silly argument.)

So where do you stand on warranty issues if you dismantle the new engine to polish it inside???

Magne

Your carb screw story is an example of bad business. If the screw was never removed, it is not the modelers fault if it was sucked in. If it had been removed, then it would be. The screws are distorted after they are installed to prevent them from comming out.

As for total dissasembly of the engine and polishing it, I do not believe any manufacturer would warrenty an engine after that. There are just too many things that can be done incorectly that will cause a failure. Just not cleaning all the grit out good enough can destroy the engine. I would say if you do that, you are going to be on your own.

That would be fair enough. If you take the engine apart, you better be prepared to accept that it is now YOURS and the manufacturer will have nothing more to do with it.


Mark