The Two Bothers Racing V.A.L.E. M-7 exhaust provided smoother power delivery and more bottom end while shedding five pounds from our stock unit.
When it comes to unleashing some hidden ponies on your motocross bike, a bolt-on aftermarket exhaust system is a common upgrade. Here at MotoUSA we like huge horsepower and riding two-wheeled machinery to its full potential, so we enlisted the help of the guys over at Two Brothers Racing who let us sample the V.A.L.E. M-7 exhaust system.
Two Brothers is known for the meticulous nature of its exhaust system designs. TBR engineers start with the muffler. A 15-inch long pre-drilled aluminum cylinder receives the signature magnesium TBR end cap and X-Lite retaining ring. Once this is completed, the header is hand matched to the mid-pipe to ensure a perfect fit every time. This type of hands-on manufacturing is what makes Two Brothers Racing hardware some of the best in the business.
On the Dyno, we gained just a hair behind a full horsepower (44.57 hp compared to 43.84 hp) with the M-7. But when compared to the stock runs, the bike kept making power at higher RPMs and had more torque with the TBR exhaust.
Although we did not gain very much horsepower, we did end up with a more linear power curve. A smoother curve in the power delivery is very important to have on these high horsepower machines. It not only makes a bike run better, but makes for a much easier and more enjoyable ride.
We then proceeded to test our new exhaust in every kind of situation to make sure it lives up to expectation. Since the M-7 comes outfitted with a removable spark arrestor screen, we took our RM-Z out to Hollister Hills OHV Park in Central California for some off-road ripping. Starting up the bike we immediately noticed the deep roar of the engine and new, unique sound. Within the first five minutes of riding it was easy to tell that the exhaust was much more opened up than stock and allowed the exhaust fumes to flow more freely. The powerband of the bike had a wider range of pull and the bottom end had added grunt, which allowed for tractoring up hill climbs and lugging through the tight single track sections.
Our next testing venue was Pala Raceway. Pala’s national caliber layout is fast paced, wide open with a couple big up-hills. Because of the track being so fast, we noticed the top-end power we squeezed out of the RM-Z and also the bottom end grunt when accelerating out of ruts.
For the final test to ensure the exhaust was as good as advertised, we took our test machine out to the most glorious place on planet earth (in my opinion). We headed out to the wide open all American sand dunes of Glamis, California. The deep sand of the dunes really calls for some horespower for the big booter jumps that we loved to hit. Once again, the exhaust exceeded our expectations by offering that extra boost off the bottom and top end.
What can you expect from a TBR M-7 exhaust system? It trims five pounds from the stock system and makes the power delivery more linear while adding a deep throaty rumble, making our RM-Z450 sound more like a man’s bike than a kid’s play toy. Once we ran it on our Dyno Jet 250i
we were a little disappointed to see that it only gained a single horsepower over the stock system. So why buy an aftermarket system, you ask?
First off, Two Brothers Racing offers a top-of-the-line full exhaust system for a cost close to half the price of their competitors. This is HUGE, we all love saving money! We love the removable spark arrestor, the unique new rumble of the engine, and most of all, the more linear power curve. On top of all that the bike lost five pounds, and we all know that less weight equals more horsepower. We definitely got what we wanted – more potential out of our bike!
Buy it now: Two Brother Racing V.A.L.E. M-7 Exhaust System
Find More Two Brothers Racing Exhaust Systems and accessories at Motorcycle Superstore. Stay tuned for phase two of our Project Suzuki RM-Z 450. Next on the agenda is to install and test aftermarket brakes and rider controls.