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Titanium alloy for forging and pure titanium material for exhaust systems have been developed. The forging alloy will be applied to production of lightweight motorcycle frames and the pure titanium will be applied to improve engine performance. The materials have been made inexpensive by the use of off-grade sponge that includes many impurities for production of titanium ingot. Stable characteristics have been obtained by controlling oxygen equivalent after setting the volume of tolerable impurities by considering mechanical properties and production engineering. In spite of low-cost, the material provides the same design strength compared to conventional material, and enables parts production with existing equipment. A review of manufacturing and surface treatment processes indicated a reduction in the price of titanium parts produced with this new material.

When measuring the stress generated on connecting rods during operation with a strain gauge there are technical problems in taking the signal wires outside of the engine. As a means to solve this problem, we have developed a wire take-out method which consists of a steel wire to hold the signal wire and a tensioner to give tension to the steel wire. The adoption of this technique made it possible to measure the stress on connecting rods at a high speed range exceeding 10,000rpm, which has been impossible before. The results of analysis obtained by the wire take-out method revealed that speed ranges exceeding 10,000rpm generated a high frequency fluctuation due to the bending vibration of the connecting rod.