Chaparral Motorsports Pro Works Episode 2: Dr. D Exhaust System Install
One the best ways you can improve the performance of your dirt bike
is to swap the stock exhaust system with either an aftermarket
muffler or full system. There are many manufacturers such as
FMF, Yoshimura, and Pro Circuit that make
quality exhaust systems for both 2-stroke and 4-stroke dirt bikes.
However, for the
Chaparral Motorsports Pro Works project bike, the in house
performance guru, Larry Brooks chose to go with a full system from
Dave Dubach of Dubach Racing Development, aka Dr. D.
With years of racing experience backed
by plenty of on-bike testing for the Yamaha Factory Race Team, Dr.
D knows how to tell when something is working and when something is
working really well. He's used his knowledge and background to
create a line of exhaust systems that are made from quality
materials and offer great bolt-on performance.
For this bike, a 2015 Yamaha YZ 450F, Larry opted to go
with the Dr. D [mageProductLink sku="drd-7571"]NS-4 complete
exhaust system[/mageProductLink], which will further enhance the
performance attained with
the Bazzaz EFI components that were installed in a previous
post. The NS-4 system (available with either a aluminum or carbon
fiber muffler) offers a reduction in weight over the stock
exhaust.
The first thing many will notice about
the DR. D pipe is that it mimics the routing of the stock exhaust
in the fact that it completely wraps the engine-which makes sense
considering Dave's long history testing for Yamaha. The
head and mid pipes are comprised of 304 stainless steel and come in
at nearly 1 pound lighter than stock. It's at the tail end however
that the real weight savings come into play as the carbon fiber
muffler assembly is about 3 pounds lighter than stock--the aluminum
muffler still lightens the overall load but not as much as the
carbon fiber. Along with being a much lighter system, the way the
exhaust wraps around the front of the engine helps keep the weight
of the bike centralized for excellent handling characteristics. And
when you think about it, shaving four pounds off a 245-pound dirt
bike can make quite a difference in handling, and overall
performance.
This system, as with all Dr. D exhaust
systems, has been track tested to improve hit, delivery, and
pulling power with noticeable performance gains. The assembly
features TIG welded construction for structural integrity and a
clean looking finish. Tucked neatly into the end of the carbon
fiber muffler is a magnesium end cap which has been riveted in
place for increased durability. The internals of the muffler
features a stepped and perforated core, while removable bolts at
the inlet cap enable removal for easy repacking. Speaking of
packing, inside the muffler features roll style packing to help
extend the life of the material.
As seen in the video above, installing the Dr. D pipe is a pretty
straight forward process, you just need to take your time and
carefully manipulate each piece of the exhaust system into place.