Build your own motorcycle exhaust kits

Why build it yourself? There are many reasons for choosing to design and build your own motorcycle exhaust system:

• No Original Equipment (OE) or Aftermarket options available
  Your model could be so old that there are no OE replacements or aftermarket options available. Most aftermarket exhausts are designed and built when bikes are new: close to 70% of aftermarket exhausts are sold within the first 3 model years, after that sales drop way off and replacement is generally done because a part wears out rather than for performance reasons. With older bikes, many of the companies that were around when these bikes were new are not in business any longer, and if they have survived, demand is often so low that they can’t justify production, assuming they still have the designs and can find where they stored the original jigs!

  Most of the aftermarket exhausts still available for vintage bikes are those that have a significant “cult” following. This is especially true for companies releasing new products – demand precedes supply. If you have a rare bike, or one that aftermarket manufacturers decided wasn’t popular enough to justify the cost of developing an exhaust, finding a manufactured exhaust could be very difficult.

  Lack of supply is also a problem on some newer bikes that are less popular or that aren’t frequently modified.

• Style
  When you design and build your own exhaust system you can tailor it to your specific bike and taste so that it doesn’t have to look like a hundred other bikes. Many times it is possible to create a design that would never be built by a manufacturer as it would be too complicated to reproduce other than one at a time.

• Performance
  Most vintage aftermarket exhausts were designed for racing or for advertising maximum dyno horsepower numbers. Because of this, they were not always street-friendly, especially on machines that don’t have heavily modified engines. Since many of the vintage exhausts still available date back to these original designs, it is often possible to design and build a more street-friendly exhaust that can give you better real world performance. Another consideration is how loud some vintage exhausts are. With increasing pressure to tone down sound levels, many times you may have to compromise all-out performance to obtain a quieter bike.

• Price
  Do-It-Yourself doesn’t always mean Do-It-For-Less. Aftermarket and OE manufacturers absorbed a lot of R&D and tooling expense in the development of their exhausts. They also buy supplies in very high volumes. So compare the cost of building your own exhaust to the cost of having anything custom built.

  If off-the-shelf options are still available, the savings in building your own design may be minimal to non-existent. Sometimes you can take a premade exhaust and make some modifications to get better fit and a more custom look, perhaps saving some time and money in the process.

  There are some decent headers available that you can make better by cutting a tube here and there, rerouting, replacing an oversize collector with a better size or design, and adding a more appropriate muffler.

  But the greatest part of building something yourself is that satisfaction you get from having built it yourself.

• History
  In the beginning performance exhausts were tested in the field. Generally the builder was a racer or an engine builder and they tested their design under real-world conditions. Then came the dyno and the competition became who could advertise the most horsepower. Early dynos were pretty unsophisticated, you goosed the throttle wide open and measured the horsepower. So what you began to see was bigger headers and bigger mufflers dumping in more fuel, to get that big horsepower number.

  But a disconnection developed between the results on the dyno and what happened in the real world. Quite often the advertised horsepower...