leaking crankshaft seal

I blew the second mag side seal this week so I decided to replace all of the bearings, I already knew that the mag side bearing did not have the outside bearing factory seal. Also for some reason the people at grubee removed the inside seal on both clutch shaft bearings. The first picture is a crank bearing the second and third are of a clutch shaft bearing. The crank bearings need the outside factory installed seal left in to help control crankcase pressure, the clutch bearing should be left sealed. With the inside seal removed the grease can liquify when hot and flow out of the bearing leaving it dry.

I'm going to use fag bearing made in Germany, they are designed to hold the grease intact to 15,000 rpm so the inside seal stays. I used this type bearing on crown forklifts at work with good results. The stock bearings are made in China, they go in the garbage. Its hard to see in the picture but you can see light through the seal and the inside race, if light can get in so can most anything else.

This is the first engine I bought and has the most miles on it, I built it assuming the quality was that of Japanese motorcycles. I did do a little porting but did not do a complete tear down. This was before I found out about the quality or the lack of in some of these engines. Overall this engine is in real good conduction other than the bearings, the transfer ports are correctly discharging toward the intake. The piston is ramped also. I bought five of these at one time and all are still running.