Yamaha's GYT-R Accessories division has been offering its own branded exhaust systems for the company's sportbikes for some time now, so we'd thought about giving the new GYT-R slip-on exhaust mufflers a try on our test '10 R1. Constructed using stainless steel piping with a carbon fiber exhaust canister that is completely rebuildable, the GYT-R slip-ons also sport nice brushed-finished stainless steel end caps for a nicely finished look. Aluminum muffler mounts and carbon upper heat shields are also included.
Installation was fairly easy, although more labor-intensive than most slip-on installations due to the underseat muffler setup of the R1. The tailpiece bodywork needs to be partially disassembled in order to gain access to the muffler mount hardware, requiring a bit of care and patience to avoid breaking or scarring the plastic. Once access was gained, however, everything went together without a hitch; because the mufflers have an internal mount that bolts them directly to the tailpiece (instead of the usual circular cradle supporting the muffler), their mounting setup was just as sturdy as stock. Even though the GYT-R slip-ons are made from stainless steel while the stock muffler construction is mostly titanium, the GYT-R slip-ons cut two pounds from the stock setup.
Also surprising was the performance gain from the GYT-R slip-ons. Although mostly mirroring the stock muffler's performance up to 8500 rpm, from then on the GYT-R's power gain is pretty substantial, with a boost of almost four horsepower at 10,000 rpm. Power continues climbing to a peak of 150 horsepower at 11,500 rpm, a 4.7 horsepower gain over the stock exhaust, with much better overrev power as well.
We should mention, however, that the GYT-R slip-ons' noise levels are higher than average. Even with the crossplane crank engine's neutralizing exhaust note, the din emitted from the large baffles on the GYT-R mufflers was fairly substantial, even at lower rpm and minor throttle settings. Usually the catalyzer quells a lot of the exhaust noise with slip-ons, but apparently not here.
The GYT-R carbon fiber slip-on mufflers retail for $999.95, and are available from your local Yamaha dealer.