The Pro Circuit Ti-6 Titanium Exhaust System is constructed of titanium throughout the head pipe, mid pipe, and canister while the end-cap is carbon fiber. I wanted the Ti-6 system because I wanted to lose a little weight as the this version of the “6s” allows me to shed almost two pounds off of the YZ450F! I also have learned that loud mufflers are not the best mufflers for power feeling on the track and sometimes putting/leaving the insert in “some” mufflers actually helps power delivery (some machines like back pressure). Installation of the PC system was painless to install (for Yamaha standards), but always make sure to install the headpipe on the cylinder head studs and then connect the mid pipe. Once the mid pipe is slipped onto the headpipe you can begin to tighten the headpipe nuts. This assures that the mid pipe doesn’t bind and is free.
So how does this beautiful piece of titanium feel out on the track? The exhaust note on the Pro Circuit Ti-6 is not near as loud or weird sounding as the older Ti-6’s that came on the 2022 or older models (had a weird flutter to them on higher RPMs). The exhaust note on the 2023-2024 Ti-6 is deeper and slightly quieter, which I personally like more. The power delivery is slightly smoother down low than stock, but only on throttle opening. At 10% throttle position/opening there is a slightly softer RPM response, which I didn’t mind on nasty, dry, choppy tracks in Southern California. Let’s face it, the 2024 YZ450F has plenty of power and managing the delivery more down low isn’t a bad thing for us older riders or guys who want to feel more connection from the rear wheel. If I needed more bottom I simply ran a more aggressive map from the Yamaha Power Tuner App and that helped the “pop” I was looking for out of corners. I usually ran the “Keefer Race Map” with the Pro Circuit system and it made me happy with the amount of smooth roll on power I had as well as low end excitement. The rear wheel definitely feels connected to my throttle hand and in comparison the PC system has more bottom end power than that of the Akrapovic that I tested a couple months ago. The mid-range is where I wanted more power out of the Yamaha and this is where exactly the PC system delivers. The meat of the Ti-6’s power out of corners and accelerating down the next straight is better than stock (most riders should be able to feel this immediately if going back to back from stock to PC). I am able to use second and third gears slightly longer with the PC system (compared to stock) and even though the low RPM response is softer than the stock system, the mid-range RPM response is more instant. Mid- range RPM response is crisp and makes the Yamaha feel “lighter” when trying to hop over square edge choppy areas of the track when accelerating. Top end pulling power is as good as stock as the PC Ti-6 doesn’t pull harder up top, but the PC system does have slightly more over-rev.
I was impressed how the Pro Circuit Ti-6 delivered and spread out its power and to me made the Yamaha even more fun to ride. If that’s possible? The PC Ti-6 Pro Titanium System runs $1,352.95 and is available over at procircuit.com
