Yoshimura R-77 Exhaust System | MC TESTED

A weight-saving, easy-to-install full exhaust system for the CBR300R.

Bolting on an aftermarket exhaust is one of the easiest ways to shed weight, improve sound, add style, and perhaps squeeze a little more power out of your bike. Yoshimura has been at the forefront of performance exhausts since 1954, and its R-77 series of pipes lives at the top of Yosh's extensive range.

The R-77 pipes feature a distinctive trapezoidal muffler. Yosh offers EPA- and CARB-compliant R-77 slip-ons and full exhausts for some bikes, but this isn't one of them. This full exhaust will end up on my CBR300R racebike, but because that machine has some engine mods we decided to test the pipe on a stock CB300F to get an apples-to-apples comparison.

In terms of weight savings, the R-77 is a home run. The stock system weighs 16.5 pounds, while the Yosh setup is a scant 6.8 pounds on our scale. That’s a substantial 9.7-pound weight savings.

Installation doesn’t get much easier. Once the CB’s belly pan was removed, it took all of 10 minutes to yank the old pipe and bolt up the R-77 system. Fitment was perfect, and the kit even comes with a spring puller that’s a welcome addition to my toolbox.

On the dyno, the R-77 showed power gains across the board. The CB’s peak output of 27.3 hp was boosted to 28.8, a gain of 1.5 hp. Peak torque is only up a smidge, but from idle on up to 5,000 rpm it’s up nearly 2 pound-feet, equating to noticeably stronger off-the-line performance.

The only downside to the R-77 is the volume: It’s loud, even with the provided baffle installed. It sounds pleasantly bassy at idle, but as soon as you open the CB’s throttle, dogs bark and neighbors scowl. Yoshimura’s tuning prowess is evident in this exhaust, so we hope Yosh comes up with a quieter, EPA- and CARB-compliant version for street-going CBRs and CBs.

YOSHIMURA R-77 EXHAUST SYSTEM

PRICE: $699
CONTACT: yoshimura-rd.com

MC GRADE: A

Verdict: Lighter, sexier, and it makes power. Now build one for the street!