15mm lowering of the cylinder head’s rotating mass. The
engine is 1 pound lighter than its brother and features a
more durable camshaft and a DLC-coated cam chainguide.
Airbox. The airbox is a two-piece construction instead
of last year’s three-piece unit. It is still closed off to most
incoming air. This is aggravated by the larger electronics
tray that holds the battery, fuel-pump relay, master relay
and black box over the air-filter opening. There is a new
airboot between the filter and throttle body that features
a new venturi shape.
Clutch. There are no changes to the Belleville washer-activated Husqvarna clutch. It uses Magura hydraulics,
unlike the KTM Factory Edition, which uses a Brembo
master cylinder and slave unit. The Rockstar Edition gets a
Rekluse clutch cover, but there is nothing Rekluse behind
Transmission. Although all the gear ratios are identical to the 2018 production bike, the Rockstar Edition’s
transmission is produced by Formula 1 supplier Pankl.
Pankl was already making the Husqvarna’s crankshaft.
There are different maps for selected gears.
Exhaust. The Rockstar Edition exhaust is shorter, with
a larger resonance chamber, shorter muffler and slip-fit
in the mid-pipe (to allow the pipe to be removed without
having to take the shock off the bike). Additionally, the
muffler still has the infamous ice-cream-cone restrictor in
it. The head stays, which doubled as pipe mounts on the
2018 production FC450, have been moved to make room
for the slip-fit juncture. In MXA’s sound tests it passed the
two-meter-max sound test.
Throttle body. The Keihin 44mm throttle body on the
Rockstar Edition breathes into a new air boot and intake
For all intents and purposes, this is the 2019
Husqvarna FC450. Virtually every part of the
bike has undergone major changes—most
noticeably the exhaust, frame and plastic
Timing. Cam timing has been changed for more bottom-end power.
Maps. The maps have been changed on the Rockstar
Edition. The stock map (#1) is slightly mellower, while the
aggressive map (#2) is slightly more aggressive. The goal
was to have a bigger difference between the two maps.
Q: HOW DOES THE ROCKSTAR EDITION’S
CHASSIS DIFFER FROM THE 2018 PRODUCTION
A: Apart from the two-stroke looking exhaust system,
most racers will not notice any of the engine changes, but
they will instantly see the new look.
Frame. The 2018-1/2 Rockstar Edition’s frame has new
rigidity characteristics. Longitudinally it is 5 percent more
rigid and torsionally it is 10 percent more rigid against
twisting. Most of these increases in rigidity come from
a thicker cross brace on the down tube, which not only
increases frame rigidity but improves the strength of
the head tube area, which suffered some failures in the
past. The geometry on the hydro-formed, laser-cut and
robot-welded frame remains the same as last year, with a
26.1-degree head angle, 22mm offset and identical weight
Swingarm. The Rockstar Edition swingarm is 5mm
longer (660mm to last year’s 655mm). Additionally, the
axle slots are 5mm longer, allowing for more wheelbase
Subframe. The new subframe is a two-piece design
that saves a half-pound. Although Husqvarna lists it as a
carbon fiber subframe, it is 70-percent plastic with 30-per-
cent carbon fiber particles mixed in.
Radiators. The radiators are mounted 12mm lower on
the frame for better mass centralization, and the cross-over
tube that moves water from the right radiator to the left
radiator is much larger in diameter to flow more fluid.
Brakes. The biggest change to the Husqvarna front