One of the first items on the "features" list of Yamaha's new YZF-R1/M is fracture-split titanium connecting rods. The advantage of using titanium rods is that, while they can display strength and fatigue properties equaling those of high-strength steels, their material has only 60 percent of the density of steel. Lighter weight means reduced bearing loads, lower vibration, and a potential for easier attainment of performance at higher rpm. In the immediate past, we have seen the adoption of forged aluminum pistons and forged connecting rods in high-performance engines, and Yamaha's move to titanium rods is a further step along the same road. As engines develop their power at higher revs, reciprocating parts must become lighter and stronger.