Yoshimura’s Pro Series Titanium Exhaust

 

When Yoshimura started back in the 70s, they manufactured parts for off road motorcycles and street bikes. With the two-stroke motocross takeover throughout the 70s, Yoshimura became more focused on the road-racing scene, where they became and still are world famous. When high performance four stroke motors started finding their way into ATVs and dirt bikes in the late 90s Yoshimura came full circle as they once again entered the market.

In 2005, Yoshimura is a force to be dealt with in ATVing. Along with American Suzuki and a host of other sponsors, they powered Doug Gust to the 2004 GNC motocross title, on a machine that many consider an underdog in the pro ranks. Yoshimura impresses many skeptics by nursing an incredible amount of smooth useable power out Gust’s Z400. We asked Yoshimura if they could only pick one performance product to help wake up the Z400, which would it be. The answer, without hesitation, was their Pro Series titanium exhaust system.

Knowing that Yoshimura produces some of the best exhaust systems available on the market, we wanted to see what effect one of their full systems would have on a mostly stock Z400. Knowing that we might want to race the machine in the future, we decided to take them up on their suggestion and purchased the Pro Series titanium system.

Construction, Fit and finish

After opening the box and inspecting all the pieces that make up this feather of an exhaust system, we instantly agreed — this hand welded pipe is a work of art. The titanium tubing is CNC bent for a precise fit. All Pro Systems come with a two-piece end cap, which has a 98DB spark arrestor insert. TEC-KIT option also has a 96DB and 93DB quiet inserts which are USFS approved. The outer body of the silencer is also titanium with the option for Carbon Fiber. This system comes with installation instructions, all the necessary springs and gaskets and even includes a handy spring installer.

The installation instructions are spot on. The cooling system should be drained. The thermostat and lower radiator hose on the right side of the quad will have to be removed in order to remove the stock pipe. Don’t try to get around this, there’s no way to remove the stock system. Two things worth mentioning is that the thermostat rubber seal can be reused and one of the stock bushings for mounting the silencer will need to be transferred to the new system, so don’t go chucking stock parts too fast. The Yosh header pipe is even designed for installation of the oem exhaust heat shield. It is well thought out engineering like this that makes the extra money for a professional system understandable.

Installation will require no modifications to the LTZ400 and the system is not even close to the quad’s plastic – so heat damage is not a concern. The fit and clearance is actually much better than the stock system. With the new Pro Series titanium system, you’ll be able to remove and install your exhaust without removing the thermostat housing or the lower radiator hose. Again, that’s well thought out craftsmanship that comes directly from Yoshimura’s extreme commitment to motorcycle and ATV racing. What’s more is the unique shape of the Yoshimura silencer allows it to clear the rear brake caliper during complete compression, unlike the stock silencer. It is amazing that a system that is so much larger can install and fit so much better then the smaller stock design.

The appearance and weight savings are very impressive as you can see from the scale shots shown below. After many hours of testing, the system looked and sounded as good as the moment we installed it six months ago. The exotic materials and high quality finish keep this system looking like new. Even the blue color change from exhaust heat on the header pipe screams performance. The complete system cleaned up well after each test and the header pipe will not rust between rides. The weight savings are evident when comparing the parts during the installation.

Time to ride

Now we can talk about the important aspect of performance. Since our testing took place on private unpopulated land, we tested without the TEC low volume insert installed. Without it the machine has a louder exhaust sound so we recommend considering leaving it installed if you ride on public land or if you live near neighbors that don’t like the sound of your four stroke.

This system instantly improved the engine’s performance and the over all handling of the quad . The increased throttle response through out the power band made the front end feel much lighter when entering a rough section under throttle. The engine pulled much harder out of turns making the quad much easier to steer with the rear wheels. The increased exhaust flow also caused the engine to rev much quicker giving the rider much more confidence when accelerating toward jumps with a short approach. The enhanced engine response also let the rider up shift quicker during starts and long straights. This will allow better starts and quicker lap times. During our months of testing, we had the chance to drag and flat track race against a stock LTZ400 and the performance gain was substantial under all conditions. In other words we constantly left the stocker in its tracks.

We tested the system under all types of riding conditions and temperatures including Northern Ohio’s snow and ice. After six month’s worth of hard core testing we removed the system to inspect it throughout. The mounts, seals, welds and over all condition were flawless! As we suspected, this quality built system is highly engineered and stood up to our testing like we expected.

The bottom line
After extensive testing and inspection we highly recommend this system be installed for any type of performance sport riding. The stronger and quicker revving power delivery aid greatly in making the Z400 an even more potent track or trail machine. When you install a Yoshimura Pro Series titanium system with aerospace type quality and materials on your quad – you’ve bolted on one of the very best exhaust systems money can buy. Speaking of money, at $745 the Pro Series titanium exhaust system is not cheap, but if you’re a believer of the saying “you get what you pay for” – you won’t be disappointed.

Tags:

Comments

comments