The YZ450F was tuned perfectly, thanks
in part to a Bazzaz fuel mapper.
A Twin Air oil cooler kept engine
temperatures down for better power.
The engine might look stock, but take a closer look. Brooks made his own motor
mounts for different rigidity characteristics. There’s also a custom case saver.
turned like no other YZ450F we have
ever ridden. Any loyal MXA reader
will recall us testing the DR.D
radiator lowering kit, DR.D engine
relocation kit and different offset
clamps (alone and in conjunction
with one another), but being paired
with Larry Brooks’ custom
modifications made all the difference.
In stock trim, the YZ450F has
a front-end wiggle during corner
entrance that causes inconsistent
rider feedback and discomfort. Most
testers found it best to steer with
the rear end for fear of what the
front tire would do. Not so with the
Chaparral YZ450F, which begged
to be laid over into turns. Excessive
input at the handlebars wasn’t
needed, but instead the chassis
worked best when we committed to
every corner. Once leaned over, the
YZ450F would feel locked into the
turn, making it much easier to keep
speed up and confidence high.
At first we struggled with the
Rekluse Core EXP 3.0 auto clutch, but
that was because it wasn’t dialed in
perfectly. After we took time to get
it properly configured, the Rekluse
worked wonders. Engine braking was
reduced and rider fatigue was lessened. Not once did we encounter the
dreaded clutch-lever pulsation that
plagued previous Rekluse auto-clutch
The powerband wasn’t overwhelming, but that was to be expected
since Larry Brooks didn’t touch
the engine. At 58 horsepower, the
YZ450F really didn’t need anything
done internally to satisfy our testers.
The Bazzaz fuel controller was a
benefit, because we never
encountered any mapping issues.
Overall, the Chaparral Motorsports
Yamaha YZ450F was a major hit.
The old-school graphics brought back
fond memories of Jeremy McGrath’s
monumental 1998 Supercross
season; however, looks only go so
far. Fortunately, the hard work that
Larry Brooks put into the project
bike paid major dividends. Best yet,
it’s possible to buy this exact bike.
All you need to do is visit Chaparral
Motorsports in San Bernardino,
California, and ask for Larry Brooks.
He will modify any bike that you
wish and also go to the track with
you to get everything dialed in.
Our project bike cost $14,500. We
think that it’s worth every penny. Not
only did we get to test an incredible
bike, but we spent the day out at the
track with one of the most knowledgeable people in the industry. That
alone is invaluable. For more information, visit www.chaparral-racing.com
or call (909) 889-2761. ❏