Yoshimura RS-9T Full Titanium/Carbon Muffler System


The 2018 Honda CRF450R is a refined version of the 2017, albeit a better one I may add. If you listened to the muffler shootout podcast you would know that this is a great muffler to add to your new Honda CR450R. If you haven't listened do yourself a favor and click on the podcast tab and look for the "Honda CRF450R Muffler Shootout Podcast". Once I got my hands on one and I took it through the ringer of the shootout process, I knew Yosh had put some R&D time into this system. We know Yoshimura works closely with the Factory Honda team here in the states and have seen the RS-9T muffler on Cole Seely and Ken Roczen’s new bikes so it's no surprise that they work pretty damn well. The Yoshimura RS-9T system only comes in a dual can set up (no single mufflers are available from Yoshimura) and is a three-piece slip fit design. Installation of the system was painless and took 15 minutes to install, which was nice to do when at the track swapping mufflers.


Once installed and on the track the Honda’s exhaust note turned from high pitch 250F’esq to a deep throaty more traditional 450 factory race bike sound. The crack of the throttle (or RPM response) is slightly smoother and less crisp, but bottom end pulling power is increased over the stock muffler. Rolling out of corners, in second gear, feels like the rear wheel has even more traction than stock and was more controllable while accelerating out of hard pack corners. The slightly smoother RPM response takes away the Honda’s excitement feel ever so slightly, but helps you gain a little more control coming out of corners. The mid range pull is healthier than stock and while the stock system had a tough time pulling third gear in tighter corners (without a gearing change), the Yoshimura system will give you an easier time rolling third gear corners. With just the flick of the clutch lever (in third gear) the Honda will be in the meat of the power once again and have you down the straight in a hurry. We noticed top end and over-rev was as good as stock (which is great). It pulls adequately down the straights in second and third gear and there wasn’t a time where I thought to myself  “I need more top end pulling power”. Ehhhhhh. No. You could tell Yoshimura was focused on bottom to mid-range pulling power when they designed this muffler system and they succeeded in doing so. It is also impressive that they didn’t lose any top end and over-rev in the process.


After weighing both the stock and Yoshimura RS-9T systems you will be saving 1.9 pounds, which is a nice chunk off of a already heavy (on paper) motorcycle. This is a significant weight loss but for $1,499.00 it is a very pricey bolt on modification. If you are looking to save a little money Yoshimura offers the stainless steel/carbon version for $977.00, but you will not be saving much weight (only half a pound). I really like the craftsmanship that went into the Yoshimura system. The welds are flawless and the mufflers tuck up inside the side number plates for a stealthy, compact look. If you’re looking for al little added giddy up and bling from your new 2018 CRF450R, the Yoshimura RS-9T system will help you on the track, but your wallet will be not as fat. This is the price we pay for getting some extra HP and a better-looking muffler right? This is one of my favorite systems for the 2018 Honda CRF450R and it has held up great over time (over 20 engine hours). You can head over to Yoshimura-rd.com to get yours or call them at 800-634-9166.



If you have any questions about this test please feel free to email me at kris@keeferinctesting.com