Pro Circuit offers their Type 296 S.A. silencer for those
looking to meet U.S. Forest Service sound and spark regulations. The 296 uses an internal metal baffle, chambers
and sound-absorbing materials to meet the 96-decibel max
sound level. It’s constructed using an aluminum canister
with a stainless steel end cap. The canister is longer than a
regular muffler’s to provide more sound-absorbing material.
The PC 296 noticeably reduced the volume on our KTM.
It exhibited the same power-changing characteristics that
are common with spark arrestors. The entire rev range was
softened. There was a little less hit down low and not quite
as much over-rev pull on top. As a spark-legal muffler, the
Type 296 is a top performer, as the softer bottom makes it
easier in traction-challenged areas while still pulling quite
well on top. The Type 296 fits right on your stock exhaust
pipe and comes with all required mounting hardware.
The MX2 Silencer is a pure moto muffler. The silencer
is lightweight 6061 T- 6 aluminum for the canister and uses
304 stainless steel for the mid-pipe. The canister measures 10 1/2 inches long as opposed to 17 1/2 inches for
the stock KTM muffler. This makes it a “shorty muffler,”
which means it’s quite a bit louder than the OEM muffler.
It allows the power to come on a little sooner and starts
pulling harder in the mid before signing off in the upper
stratosphere. The MX2 silencer really wakes up the power
characteristics of the Bill’s pipe. The only real issue is the
sound level. It’s too loud for anywhere other than the racetrack, but that’s what it’s designed for.
The Scalvini silencer is not a U.S. Forest Service-approved spark arrestor; it’s a closed-course race muffler
designed to complement their pipe. The muffler has an
aluminum canister with a carbon fiber end cap. It has an
open-core system like the stock KTM muffler. It comes
with a metal strap that has to be wrapped around the canister to form a mounting bracket. The strap itself was easy
to form around the exhaust and held securely. The issue
we had with ours was that the bolt and spacer wouldn’t
work on our frame. The bolt had the wrong thread pitch,
and there seemed to be a spacer missing to fit inside the
rubber grommet. We remedied this by borrowing the spacers from our FMF muffler, which fit right on. Like the pipe,
the Scalvini muffler is a work of art. The decibel level was
the same or slightly quieter than that of the OEM muffler.
This was a little surprising, since the canister is only 12
inches long, 5 1/2 inches shorter than the KTM muffler.
Typical of a shorter muffler on a two-stroke, this one
makes the motor snap to life sooner. The power comes on
faster and harder than with the stock muffler. As a full-race
package, the Scalvini pipe and muffler combo resulted
in the greatest power gains we experienced. The only
drawback to the combo is that the short muffler made the
power almost too intense, too instant. This could prove to
be a handful in low-traction conditions. On our tacky test
track, this combo was lethal—but so is the price tag. It’s
not a cheapie. ❏
PRO CIRCUIT TYPE 296 S.A.
BILL’S MX2 SILENCER
TRACK AND FIELD TEST
SCALVINI ALLOY SILENCER
We tested the FMF Q Stealth last month praising the smooth
power and soft exhaust note.