Difference between revisions of "Yamaha TZ350"

Minor porting, piston and exhaust upgrades saw the peak horsepower output up by 2 to reach a claimed 64bhp @10,500rpm. The factory also chose to fit an offset, angled plug head with the "D", in an effort to combat cylinder and piston distortion as well as slightly raising the [[compression ratio]]. New expansion chambers were now fitted from the factory with removable silencers. Small changes were also made to items like the base gasket, crank webs, small end bearings, the gasket for the side oil draining bolt on the gearbox, carby floats and choke systems etc.  Tyre widths were also increased from the factory though rim sizes remained as per the previous model.

Not to say that the TZ350 became uncompetitive with the introduction of the "D", quite the contrary, with customer bikes winning 350cc races and domestic championships across the non-USA world from 1977 through 1978. (America didn't run a 350cc class but allowed 350cc bikes to run in other larger capacity classes.)