Does your allegiance fall with FMF or Pro Circuit? Do you prefer the Italian Scalvini exhausts for the cone look? Did your uncle tell you Bill’s is the best and now you are trying to hide the package in the garage from your wife? After market exhausts are usually one of the first big investments most riders make. Sometimes its fueled for the aesthetic looks but claiming its for performance is the justification. Let me give you a little insight and hopefully teach you a thing or two so you can make the best purchase for your two stroke dirt bike.
The major brands in the aftermarket exhaust business all make good product. FMF, Pro Circuit, Bills and Scalvini have all been around for decades and you can expect an improvement by going with any of these brands. Were you aware that FMF and Pro Circuit both offer different silencers and expansion chamber shapes and lengths in order to best suit your riding style and discipline? Silencer length has a big impact on power and the difference can be seen in different dirt bikes applications.
Here, we are looking at Graham Jarvis’ Husqvarna motorcycle and the important thing to note is the length of the silencer. Notice how long it is? This is due to the fact that Graham is an off-road oriented racer and he will more than likely value broad useable power compared to hard hitting and quick revving power. Photo: Future7Media
Then we have Ricky Carmichael racing his Suzuki RM 250, notice how the silencer doesn’t stick out past the number plate. A shorter silencer accelerates faster and produces a harder “hit” in the power band. This photo was taken at a Supercross race where quick and hard hitting power are very important. Photo: MXA
When it comes to the expansion chamber this also plays a very important roll with power location. Pro Circuit Offers two options when it comes to power delivery. They have a Works pipe which is raw steel and is their motocross oriented pipe. They sell a platinum coated version which is the same performance but platinum coated for ease of maintenance. Then they sell the Platinum 2 pipe which produces a broader power curve for more off road oriented riding.
When it comes to FMF’s offerings head to their website so you can read the difference between their Fatty, Factory Fatty, Factory Fatty Rev Pipe, and Gnarly Pipe. It is a lot of reading but it is very interesting to see how the shape of the exhaust system can manipulate power.
So what does this all mean for you? It means don’t fall victim to exclusively only buying one brand. The best and most informed decision will be made by you riding your dirt bike and after spending time on it, determining where you need power. Maybe you have pledged allegiance to FMF all your life but you read that Pro Circuit increased over rev on your model and year and that’s what you have been wanting. Read the reviews from quality sources and ask around the pits. Someone will absolutely give you their opinion or someone may have the same bike and exhaust and you may get to try it out. By no means are the brands I listed above a comprehensive list of all the brands or offerings available to the public.