Yamaha YFZ450R Trail Enhancement

Dialing It In

Let It Breathe
In order to gain a little bottom end power and even some throughout the whole powerband, I installed a Motoworks SR4 full exhaust system along with Motoworks Fuel Management Interface (FMI). The exhaust system practically fell into place, which is actually somewhat unusual for an aftermarket exhaust system. As for the FMI, installation on that was fairly easy as well. The hardest part was removing one of the plugs from the fuel injection because it was such a tight space and the clip did not seem to want to come out. Otherwise, it was literally plug and play. I nicely routed the wiring so that I could mount the FMI behind the airbox and grounded it on the battery. I then removed the airbox lid to allow more air to flow into the motor. Once I was finished with installation, I immediately cranked it up and it sounded like a new machine. A low growl became very apparent throughout the shop and I was sure we had uncovered something special. Out on the trail testing, it was apparent to me that the Motorworks SR4 full exhaust and FMI made a tremendous difference in the motors performance. This setup really woke up the YFZR beyond my expectations. It literally gained power across the powerband and most importantly, it pepped up the bottom end power to perfectly match what I was looking for.

Handling
I have to admit, I was stoked when two boxes arrived in the mail with Fox Shox logos on them. I had ordered a set of Float X Evol shocks for the front and a Podium X for the rear. I have always heard that these guys have developed a killer suspension setup. Mounting them up was fairly easy, but did take a little time and effort. First off, I mounted up the front Float X Evol shocks with ease and installed the roost deflectors. Things got a little trickier on the rear as both the rear plastics and the pipe must be removed to exchange out the stock shock for the new Fox. While it was lifted off the ground, I added 35 psi to the main chamber and 120 psi to the EVOL chamber. I set the ride height to 9.5 inches in the front and 8.5 in the rear, which seemed about perfect for the type of riding I was doing. When I got out on the trail, I immediately noticed a huge difference in comparison to the stockers. I brought along with me a screwdriver and a wrench so that I could make the proper adjustments to the high and low speed compression and the rebound. I messed around with it on and off for a couple of hours until I was able to get close to my dream setup. Believe me, these shocks are worth the money, but let me warn you that you'll have to spend some time setting them up to your personal liking so that you can gain maximum performance. I expect that I'll continue to dial on mine. At this point, I can now hang on to my YFZR through the worst of it while remaining confident and holding higher speeds.

Width & Meats
As I mentioned previously, I thought I might have a simple yet cost effective way of losing some inches in the width. Since I own the older model YFZ-450, I grabbed my older set of Douglas Shamrock beadlock wheels, which use a 4+1 offset in the front and mounted them up. Although shedding those near two inches may not seem a lot, try jamming 50 inches of ATV through two trees spread 50 to 51 inches apart. A small problem with my theory is that the rear wheels remain stock offset. My thinking is that if I can get the front tires through the trees easier, the rears will usually follow without hanging up. Secondly, the Douglas beadlock wheels will help in keeping the bead from dismounting during hard runs.