One of the first things most riders do to a new motorcycle is modify the exhaust. Sometimes it's to get more noise, sometimes it's a fashion statement, sometimes it's to get more power, and occasionally it's all three. In the process of deciding what modifications to do, we are confronted with the choice of slip-on mufflers or a complete exhaust system. What is best?
'Best' is, of course, a pretty subjective term at best. One man's 'best' is another mans 'bad'! So how about if we stick to the facts and let you decide what's best to the facts and let you decide what's best for you? And since most sportsbike owners replace the exhaust system than any other motorcycle style, let's assume more power is your goal.
If you're on a tight budget, slip[-on mufflers might be your only choice because, by and large, this is the most economical route to take. This is not to say that slip-on are not an effective solution. Slip-on mufflers are designed to – you guessed it – slip on to stock header pipes, and they can make a substantial horsepower increase. It should be noted, that most motorcycle build after 2007 have catalytic converters in the header pipes. From an emissions standpoint, slip-on mufflers do not constitute tampering since you are not removing the catalytic converters. As far as the noise is concerned, should you decide to risk riding a motorcycle with modified exhaust on the street, a little discretion goes a long way toward not having problems with the law. If a complete exhaust system is within your budget there are a number of designs to choose from. Keep in mind that by installing a complete exhaust system, you will be removing the catalytic converter on your motorcycle, so these are only legal for closed-course racing applications.
We do recommend either a exhaust system with some sort of crossover or a 2-into-1, 4-into-1 or something similar. That's because, the crossover performs an important function. In technical terms, we say that a crossover, or a 2-into-1 design, detunes the system, Detuning something might not sound like a good thing, but in this case it really is. What it means is that by connecting the two pipes together, we not only increase the available volume we are trying to stuff a load of exhaust gas into, but we are also effectively eliminating the inevitable resonance that any long unobstructed tube will have.
The effect of resonance in an exhaust pipe is that the engine will come onl like gangbusters at an rpm range where the resonant frequency of the pipe is favorable, but there will also be an rpm range where it won't run so well. By detuning the system we get a wider, flatter, more useful powerband.
Another option for a complete exhaust replacement is combining a set of performance headers and a set of slip-on performance mufflers. There are several advantages to this setup, for example, have a crossover to detune the system, but it's hidden so as not to obstruct the view. Another advantage is that you have more types and styles of mufflers to choose from. Everybody likes choices! Besides, you don't have to install both at once, so the cost can be spread out.
So, now that you know what's up, you can decide what's best for you....