Today's engines, in World Superbike form, rev to more than 15,000 rpm reliably, allowing them to make almost 50 percent more power than 1982 Superbikes. With liquid-cooling, pistons survive at compression ratios a third higher than the 9.0:1 or 9.5:1 of the days of yesteryear—numbers that translate directly to increased torque. The cooler pistons run, the longer it takes for fatigue cracks to form. To operate at today's higher revs, stronger internal parts are essential—forged rather than cast pistons, shot-peened alloy steel or titanium (the fracture-split rods in the YZF-R1) connecting rods rather than the lower-spec steel rods of before. Titanium valves—40 percent lighter than steel—are a key to today's higher peak rpm, assisted by valve springs made from ultra-clean, super-fatigue-resistant Japanese wire. On his way back from victory circle at Daytona one year in the 1980s, Fujio Yoshimura stopped to say to me, "This is the first time this race has been won using Japanese valve springs."