aluminum silencers. The chamber
hangers are single pieces of steel
strap, welded at the end' only, and
there is no centerstand stop. When
installed, the expansion chambers
touch the inside of the lower fairing
and make burn marks.
The RSC/Noguchi pipes weigh
3.75 pounds each.
For the run with these pipes, we
left the jetting as set for the Toomey
pipes; 370 main jets with the air box
disconnected.
The Yamaha's best pass with these
pipes was 12.57 sec. @ 106.25 mph,
and each pass was quicker and faster
than the one preceeding it. But the
RSC pipes are outrageously loud;
each launch sounded like the start of
a Formula Two race. And while peak
power was obviously increased, the
powerband was reduced. The Yamaha
had to be powershifted at 11,000 rpm
or else it fell off the power band below 10,000 rpm - when it went
into the next gear.
On the powerband, at high rpm,
the Yamaha wheelied suddenly when
the throllie was 'wacked open in the
lower gears.
More can be done to make an
RZ350 run than simply boIL on pipes,
and Gary Schumate of Specialists II
specializes in doing just thaI. So we
tried out Schumate's own RZ350, set
up with Imm milled off the cylinder
head, 30mm Mikuni ~rbs (stock carbs
are 26mm) and a set of his own pipes.
Schumate's pipes have aluminum
silencers that come apart for rebuilding when a snap ring is removed. The
pipes weigh 5.5 pounds each, have
triangulated two-piece chamber hangers welded at the end and sides, and a
ce~terstand SLOp. They sell for $225 a
pan.
Stock U.S. RZ350 with Toomey' pipes: 12.61 sec. @ 105.50 mph.
The bike's best pass was 12.69 sec.
@ 104.40 mph; a dozen passes couldn't
better those figures, and we'll tell you
why in a minute.
Schumate's bike had an excellent
powerband and was much quieter
than the stocker equipped with
Toomey or RSC pipes.
Which brings us to the Frenchmodel RZ350 illegally imported into
this country by a good friend of ours,
(Continued to page 26)
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