xz 550 RJ/RK
This bike was made by Yamaha in 1982/83. Power
is a twin-v, water cooled, 4-valve twin overhead cam engine with
a 12,000 RPM redline. Chassis is shaft drive with mono strut suspension,
dual front disk brakes, and cast aluminum wheels.
To be more exact the initial "RJ"
('82) model had no fairing,a single front disk brake, and no gas
gauge. It suffered from possible carb stagnation at initial acceleration.
Later in '82 a small sport fairing (pictured above) was offered.
the "RK" model had a modified carb setup to include
an acceleration pump. Twin disk brakes were added, a gas gauge,
and a full custom sport fairing with mirrors (pictured here).
This bike represented a different direction
for Yamaha in '82: a little high-tech and styling to start competing
with the growing "Ninja" market. Though not a great
sales success, it has a small following of those who appreciate
affordable neck ripping performance and those who race it. It
is deceptively fast with great high-end torque and light handling
for the hillside ride.
But it also has the associated annoyances
expected from an older somewhat experimental bike by Yamaha. In
short, the electronic ignition and charging system can fail (poorly
build). And, the gas tank is not the greatest design and tends
to rut out in several spots.