The heart of Yamaha Tracer 9 GT+ it’s the front-facing three-cylinder. It has a displacement of 890 cc (bore 78.0 mm, stroke 62.1 mm). It is fed through ride-by-wire throttle bodies, each of which has a duct of dedicated length and shape, for the benefit of both delivery and sound: the company’s Music division contributed to the development of the intake and exhaust systems for ensure that the “voice” of the engine was as beautiful as possible. The distribution is a double overhead camshaft controlled by a chain, with a thin shoe tensioner, and there are four valves per cylinder. The pistons are forged and combined with connecting rods with separation between the cap and half-head obtained by fracture.
The compression ratio is 11.5:1. The crankshaft has crank pins staggered by 120° (the firing order is therefore regular, every 240° of rotation of the shaft) and is combined with a countershaft to dampen vibrations. The cylinders are direct-ported and are mounted with an offset (forward) from the crankshaft. The clutch is with multiple discs, in an oil bath, with anti-slipper. The gearbox is electronic, bidirectional and it has a new operating logic: the possibility of downshifting with open throttle and switching to “longer” gears with closed throttle has been implemented on the GT+.
Maximum power and torque declared are 119 HP (87.5 kW) at 10,000 rpm and 93 Nm (9.5 kgm) at 7,000 rpm. During the testing of the Tracer 9 GT, our Test Center recorded a peak of 119.0 HP at 10,000 rpm and 93.9 Nm at 7,000 rpm at the crankshaft.
