Just started thinking-it seems pretty common that if you get more than 9000km/s out of a wr engine without a rebuild then you are doing well. Why do we accept such poor workmanship? The reason I ask is because I have had numerouse Yammi R1'S/r6's that have 4 x 250 cc 5 valve pots in em that are running just as bloody hard (up to around 18500 redline by memory?) and have yet to hear of any engines needing rebuilds, and have heard of a number of bikes doing over 100,000 kms without a rebuild. Sooooo what gives? wheres the flaw in our engine?