The KX450F from our test fleet had logged many hours
over the course of the year, so Precision Concepts offered
to lend much-needed help rebuilding the bike. Ty Renshaw
was lead mechanic on the build and was going to be on
the team until he got called up to the major leagues to be
on Precision Concepts’ professional team.
The engine was completely torn down and every part
cleaned and inspected for wear. When preparing an engine
to run hard for 24 hours, making sure it’s fresh to start
with is a must. And with the time Tilley had logged during
the year on this bike, we were surprised how short the list
was of parts that needed replacing. We rebuilt the engine
with OEM parts, with one very important exception: a complete Rekluse Core manual clutch. A complete clutch from
Rekluse consists of a high-grade, CNC-machined, hard-anodized aluminum clutch basket; pressure plate; inner
hub; stainless steel, heat-treated springs; and a proprietary
pressure plate design with locating clutch spring pockets.
Twenty-four continuous hours on a bike is murder on a
clutch, especially on the demanding trails at Glen Helen.
Although we made minimal changes internally for
performance gains, we did bolt on some external performance parts, keeping in mind that
smooth power and rideability were priorities.
We added a Mototassinari Air4orce tunable intake
system for more air volume and the option of two differ-
ent velocity stacks. Along with the new intake, we installed
a Pro Circuit airbox screen-eliminator kit. We topped off
the engine modifications with Pro Circuit’s all-new T6 com-
plete exhaust system and custom Precision Concepts ECU
mapping designed for improved fuel mileage and smooth
power delivery. Precision Concepts also installed Kalgard
Pro Comp4 10w40 full synthetic engine oil, reflective heat
Ricky Brabec gasses
the Ty Renshaw-built
KX450 through a Glen
Helen sand wash en
route to fifth overall.
Ryan Abbatoye Designs gave the
KX450 style and pink backgrounds
for breast cancer awareness.