It is no secret that the 2002 CRs have a poor airbox design. True,
it is a standard procedure to tear any new motorcycle's airbox
apart to seal it with your favorite silicone, but this is beyond
the usual "fix". The main problems lie in two areas: 1) The airbox
flexes, forcing a break in the seal between the airboot and the
airbox. 2) The surface where the airfilter seats against the airbox
contains protruding nubs. These nubs obviously hinder a good seal.
MX Bonz created a kit to alleviate this problem.
Chop, Cut and Dust No More....
The MX Bonz kit cures the
sealing problem by bolting two CNC created aluminum rings together
to seal the airbox to the airboot.
The installation, as MX Bonz puts it, is major
surgery; but if you are even somewhat mechanically skilled, and
have the right tools, you should be ok. You will need the following
to complete the task: an X-acto knife, razor blade, 10mm wrench,
rachet/10m socket, silicone sealant, phillips screwdriver, and a
little patience. To sum up the process, the airboot needs to be
seperated from the airbox. After all of the previous sealant is
cleaned, we suggest to sand the surface which will receive the
silicone with a relatively course sandpaper such as 80 grit or a
red scotch brite. Then you'll need to cut off the five nubs inside
the airbox; this is where the time lies. It is tough to get in
there easily enough to shave each one down flush with the surface,
but be patient and it'll work out.
Note how the inner and outer
ring are secured together with six bolts to solidify the
seal.
The result? Until now, I have had problems here
and there with a fine mist of dust in the airboot. but with the new
MX Bonz kit, the airboot is cleaner than it ever has been. This has
been an ongoing, perplexing problem, but it appears as though the
problem is no more.The ultimate test was
competing in the recent WORCS race in the Utah desert. The two hour
course followed an eleven mile loop of mostly silt, which was
nothing short of blinding. Some of the berms contained twelve solid
inches of pure talcolm-powder-like silt. That alone will clog an
air filter in one lap, let alone two hours of racing.
The thin OEM outer ring is
replaced by their solid CNC machined aluminum ring.
The result? The filter was the most filthy I have
ever seen it after the two hour WORCS race, yet the airboot was
free of dirt. The worst part about trying to figure out the sealing
problem, is that there is no way to simulate the problem with a
control within the "experiment". Many CRF owners have suffered
problems with getting dust in the airboot, which may be simply a
filtration problem, but the MX Bonz kit provides solid peace of
mind to ensure an airtight seal between the airboot and
airbox.
MX Bonz CNC Airbox
Fix Prices as tested: $59.95
Holeshot
Endo
Ensures a proper seal between the airbox and
airboot on 02 CR 125s, 250s, and 450s
No more "nubs" interfering with the air filter
seat
The installation task requires patience as a
few of the steps are somwhat frustrating, but feasable none the
less
Off-Road Videos - Check out over ten years of extreme 4x4 action, product testing and the Off Road Nation at play. Baja racing to rock crawling, ATVs in the sand to motorcycles in the dirt, it's all here. Rate them, share them and upload your own.
ATV Reviews - Honda, Suzuki, Yamaha, Polaris, Kawasaki, Can-Am. First rides to long-term tests, check out the latest in ATVs, UTVs and Side-by-Side vehicles of every make and model. Read expert opinions and follow custom project vehicles.
