Overview: What am I looking for in an exhaust?
The first thing to ask yourself is why are you interested in a new exhaust? Is your current exhaust not working, broken, etc? Are you looking for better performance? Are looking for a more customized look? A better sound? These are important questions because the price and quality of exhausts out there revolve around these questions. And after all, if you're putting several hundred dollars into a new exhaust, you should get what you want!
Stock vs Aftermarket
When replacing a broken or old exhaust for an ATV or motorcycle, the first question might be - Should I buy stock? There really might not be a good reason to buy stock. Stock exhausts are not made by the best of engineers. When an exhaust is designed, they have to meet USFS and other legal standards, and for engineers who have a laundry list of other parts to design, they don't generally focus much on great performance in the exhausts. The exhausts are generally made from steel which is a very heavy material. Exhausts are also typically chromed, but are very susceptible to rust and require a lot of maintenance to keep it looking good. So not only do you have lower horsepower because of the higher weight, you have an exhaust that might not look the best and requires constant cleaning. And to top it all off - its most likely going to be much pricier than most aftermarkets.
So I'm looking into an Aftermarket Exhaust. What now?
There are several industries that just specialize in exhausts, such as HMF, Two Brothers, Motoworks, and Yoshimura. These companies have engineers that take a look at the make and model of a bike, create a good fitment, and then model the inside of the exhaust as well as the material to get the best horsepower and sound. Most exhausts fit a small few makes and models. Some may only fit one model/make of an ATV with a limited year range, some may be able to fit several makes and models. The first step is to look at the companies available. Although there are many manufacturers to choose from, for the sake of this articles size, here is a brief review.
HMF: Low prices, large range of customizable colors, decent performance.Two Brothers: Higher prices, moderate range of customized look, great performance (specializes in dual exhausts).Motoworks: Lowest prices, limited range of customized look, better than stock performance.Yoshimura: Higher prices, moderate range of customized look, great performance.
This is not so much of a guide to tell you what is the best manufacturer, but to let you be aware of how they range. Almost any aftermarket exhaust will give you better horsepower than stock, but some are geared towards a customized look, some are geared towards the best performance, and some are geared towards being the most affordable.
A Brief Look at Terms
There is a special set of words used in the exhaust industry. Knowing these will help you buy the right exhaust and save money.
Slip-on: A slip-on exhaust is generally just a muffler. Not all makes and models of a bike can just have a slip-on replacement, some require the entire exhaust to be replaced. Slip-ons can be at least $200 cheaper than a full exhaust because they don't include the header / mid-pipes.Full / Complete System: This is an exhaust that includes an entire replacement - muffler, header pipes, mid pipes. Its generally more expensive.Header / Mid Pipes: These are the pipes that are generally "hidden" within the bike. They connect the engine to the muffler and generally are not decorated or painted.USFS: United States Forestry approval. They require flame and sound restrictions on ATVs.Spark Arrestor: This is a small screen that is meant to reduce the flames exiting the muffler. A spark arrestor is required to be included with exhausts, so make sure one is included! The best option is to have one is removable.Quiet Core: An insert into the muffler that helps quiet the exhaust. A decibel measurement should be included in the information about the core, generally the level is around 90 decibels but is different for various parks. Quiet Cores are usually an additional item purchased with an exhaust, but some exhaust series include it in the pipe already.Dyno chart: A chart that measures the power of an exhaust. See below for the paragraph of how to read a dyno chart.
How to read a dyno chart
Not all exhausts have a dyno chart publicized, but if they do, its a great source of information to see how much torque and horsepower you can get out of an exhaust. It measures the torque (force needs to cover a distance, ft lbs.) and horsepower over RPMs. Some dyno charts show both torque and HP, some only show one of the two. On the bottom will be the RPMs. For example, a dyno chart may show that a bike has 21 HP at 1200 RPMs. When a dyno chart compares two bikes (with a stock exhaust and the aftermarket exhaust), generally you want the exhaust thats line places higher up. Some comparisons can also show a difference in power at different lengths of a bike ride.
Breaking it down: Buying at a low Cost
So you're ready to buy and you want something affordable? Remember to look for these things: An exhaust that is made of some type of aluminum and not carbon fiber (carbon fiber is much more expensive), a slip-on (unless you need a full exhaust replacement), that does include a spark arrestor and hardware (despite how cheap an exhaust is, these two things are a must). Color on an exhaust, if available, is generally not too much more money - maybe about 20 to 40 bucks.
Breaking it down: Buying for Performance
So you're ready to buy and you want something with a lot of horsepower? Not all manufacturers will have a lot of information, but if available, pay attention to the HP & Torque gain, the difference in weight, the exhaust series, and the dyno chart. Exhausts can often be pretty much the same inside and out, but some series are very new and innovative, such as the HMF Competition Series that features different inserts to alter the power and sound. If you race periodically, looking for an exhaust that has additional adjustable features like this can make a big difference.
Breaking it down: Buying for Looks
Some manufacturers stick to the basics: Sticker, aluminum, chrome or brushed finish, done. Some go farther. Generally, the exhausts are either made of aluminum or carbon fiber. Carbon fiber is lighter than aluminum and at least $100 more expensive, and can be more fragile, but has a great look to it. Aluminum is generally powder-coated in different colors.
Other Tips:
If you are buying online, don't buy straight from the manufacturer! You are likely to buy the exhaust at full retail and pay for shipping. There are plenty of powersport online stores and eBay sellers that sell new exhausts they buy from the manufacturer. Also, many sellers offer free shipping on orders over $100-$200, and generally an exhaust will be over that amount.
Research! Don't buy from the manufacturer, but do visit their website! A simple Google search will bring up many manufacturers. Do your research, and an individual seller will generally not have any more information that the manufacturer doesn't.
Look at reviews - Information can be found on online forums and reviews of exhausts that won't be publicized by the seller or manufacturer. For example, on the manufacturer's website you'll find installation instructions, but on a review of that exhaust, you can find out just how exactly difficult the installation is.
Sara works in the advertising and online sales of Street N' Dirt.
Street N' Dirt is a branch of an OEM Kawasaki, Suzuki and Arctic Cat parts and accessories dealership. Among these companies, it also sells aftermarket accessories for ATVs and Dirt Bikes. Some of the aftermarket companies Street N' Dirt sells is HMF Engineering, Pro Armor, Cobra, Motoworks, Factory Effex, any many more!
Street N' Dirt has two main webstores:
http://www.leesonsarcticcat.com/
http://www.streetndirt.com/
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