JustErik

Since no one really addressed this question, I'll throw out my opinion. Last Fall, I was told by a flying buddy that the bearings in my Saito 100 sounded bad. I didn't know there was anything wrong. The engine started easily, had gobs of power and was as reliable as I anyone could want. After changing the bearings, however, I could hear a huge difference. Below 3,000 or 4,000 RPM, the predominant sound I now hear is the swishing of the big 16x4W APC prop and the sound of the valve train doing it's thing. It's a remarkable difference.

Before the new bearings, there was a pronounced rattling sound that got progressively worse as the throttle was advanced. It's hard to describe, but I'll know it again when and if I come across it again. The need for new bearings was also demonstrated by showing me the end play in the crank. Grabbing the tip of the prop and pulling/pushing it backwards and forwards yielded a lot of play and distinctive clicking noises as the crank moved around. With a little guidance (from an online buddy on another site), I was easily able to install new bearings from Paul at RC Bearings and now the engine is 100%. I'm almost looking forward to the next time I have to do repair work.