Yoshimura Zrs Slip-Ons
YOSHIMURA ZRS SLIP-ONS
CW EVALUATION
Peace pipes
IF THERE’S A PROBLEM WITH most aftermarket exhaust systems, it’s that they’re too loud. Your neighbor on the starting grid won’t complain, but the guy who lives next door may not be as understanding. Keeping the peace should sometimes be taken literally.
Fortunately, aftermarket exhaust-makers are not blindor deaf-to the din they have created. And Yoshimura (4555 Carter Ct., Chino, CA 91710; 909/628-4722), for one, is doing something about it.
The Japanese high-performance company now offers its Zyclone slip-on mufflers for sportier Triumphs (and complete 3-into-1 systems for the Triples). We ordered up a set of slipons to fit our long-term Sprint 900.
Yosh offers its slip-ons in three styles: polished aluminum ($276 per pair), black powdercoat ($10 additional per side) and carbon-fiber ($105 additional per side). Buyers can also choose from four types of baffles: standard; straightthrough competition; a two-chamber ZRS ($40 additional per side); and an EPA-certified, street-legal, three-chamber unit ($75 additional per side). Do the math and you’ll find that prices range from $276 to $636 per pair.
We opted for carbon-fiber canisters equipped with ZRS baffles, taking the price to $566. We chose carbon for two reasons: It looks great with the Sprint’s blacked-out engine, and it is very lightweight. Our pair of slip-ons weighed 15 pounds, 7 pounds less than the Stockers.
Fit and finish are flawless. The mildsteel pipes are painted black, and polished, CNC-machined aluminum end caps and adapters bracket the repackable canisters. For those riders who don’t want to attract the attention of the local constable-or those snobs who don’t want the name of a Japanese company on their Euro-bike-the mufflers are available without the Yoshimura nameplate. The familiar Yosh “3:47” (well, that’s what the Japanese symbols look like, anyway) logo is subtly machined into the end caps, however, right above the exhaust outlet.
Installation is a snap, requiring the removal and replacement of just four fasteners. The most laborious aspect of the installation is pressing the centerstand rubber into its hole in the leftside pipe; you can wrestle with the rubber all day if you don’t know the trick-spraying it with Armor-All. Our only beef is that the pipe-clamp bolts are too long, which is a bit unsightly. Better that than too short, however.
Firing up the Sprint with its new mufflers, we were pleasantly surprised to hear that its exhaust note was scarcely louder than stock, giving the Triple’s characteristic growl a slightly sharper edge. These are truly the quietest aftermarket mufflers we’ve ever sampled. Yoshimura claims an increase of only 4 to 5 decibels with the ZRS baffles, and we believe it.
Even better, the bike ran great with stock jetting. On the CW dynamometer, the Yosh pipes gave the Sprint a 2to 3-horsepower advantage between 5000 and 6000 rpm, added a similar amount from 8000 rpm to its 9500-rpm redline, and mirrored the stock readings everywhere else. Though peak torque remained the same, the Stocker’s 5500-rpm dip was shifted slightly lower, to 4000 rpm. Throttle response was crisp throughout the range.
Attractive, lightweight, powerful and quiet: What more could you ask from a set of replacement mufflers?
