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The more you know, the more fun customizing your bike gets! Customization Q&A (Exhaust)

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     15 min read

    Customization lets you create a bike to your own personal specifications. The installation of functional parts, such as those used in racing machines, will improve performance and get you fired up! But, are they really making a difference? If you don't ride fast, do you really need them? Let's get some answers to these questions in order to enjoy customization to the fullest!

    Replacing the exhaust has always been the most popular customization method! However, today's motorcycles are fast enough with a stock exhaust and you might think it's a pain to figure out if aftermarket exhausts conform to the ever increasing regulations. But don't give up there! Both ride quality and looks will change drastically just by putting on a new exhaust!

    Q: If I replace the exhaust, will I get more power?

    A: The benefits of exhaust replacement are not limited to increased power.

    Replacing the exhaust with a high-performance one will change the look, sound, and feel of the bike. Although recent bikes are fast enough even with a stock exhaust, it would be a waste to think that there are not enough benefits to exhaust replacement because of this.

    First of all, power is improved not only in the peak range near the fully open red zone, but also evenly throughout the entire range from low RPM. Additionally, more and more products are now focusing on "ease of opening the throttle" by increasing torque in the normal mid-RPM range and achieving a smooth response without "dips". This is very effective when trying out riding techniques such as opening the throttle when going into a turn. In addition, the use of high-grade materials such as titanium, which is not used for stock products for cost reasons, results in overwhelming weight reduction. This affects the ride quality, such as achieving more dynamic handling. Above all, the change in look and sound is obvious at a glance! In the past, and still now, exhaust replacement is the most appealing customization method!


    ■The increase in power, of course, but also the ease of opening the throttle and the dynamic handling will have a positive effect on ride quality and riding technique. Of course, the look of the bike will also change drastically.

    Easier handling

    The silencer of a stock exhaust is quite heavy and is often placed on the side of the bike, away from the center of gravity. However, the silencer on an aftermarket exhaust will be much lighter and usually has a shape and layout that minimizes outward protrusion. This means that the silencer will produce less inertial force due to its weight than the stock exhaust, which contributes to the centralization of mass and makes leaning the bike when cornering feel lighter and more dynamic. Of course, the weight of the exhaust pipes also affects the overall weight of the bike, helping to improve mobility.


    Installing a full exhaust will result in a considerable weight reduction

    The weight of a stock full exhaust system for a large-displacement 4-cylinder engine is quite heavy: approximately 20kg for a flagship model with a dual exhaust, 12 to 15kg for a standard naked model, and 8 to 10kg for a supersport model. In contrast, an aftermarket exhaust is usually about half the weight, or even 70 to 80% lighter, depending on the product! A stock 250-class silencer weighs about 5kg, but a lightweight slip-on silencer weighs about half that. "Light is right" for sportbikes, and light weight is a great advantage in all situations.


    ■Stock exhaust: Approx. 20kg


    ■OVER Racing exhaust: 7.9kg; a whopping 12.1kg weight reduction!

    Easier to lift and push

    The weight reduction effect of exhaust replacement can be felt just by lifting the bike after you've parked it using the side stand. Especially for big bikes that always feel heavy, it also becomes easier to maneuver the bike in and out of garages and parking spaces, so the benefits are huge even when you're not riding.

    Improved acceleration

    Many high-performance aftermarket exhausts have excellent transitional characteristics when raising RPMs and improved torque characteristics. This makes it easy to open the throttle in any RPM range and enjoy powerful acceleration and stable cornering with good traction.

    Better sound quality, not volume

    Exhaust pipe merge methods and silencer structures are always being developed in pursuit of sound quality as well as horsepower and torque improvement. You can enjoy a sound that fits the characteristics and category of your engine and bike model, from piercing high-frequency sound to pulse-pounding bass.

    Q: What types of aftermarket exhausts are there?

    A: Full exhausts and slip-ons are the two types.

    There are two main types of exhausts: Full exhausts, which replace the entire exhaust system, and slip-on exhausts, which replace only the silencer (sometimes including the tailpipe).

    Full exhausts will change power, torque, and engine characteristics, and can also significantly reduce weight. For a naked bike with an exposed engine, you can also enjoy the beautiful curves of the exhaust pipes.

    Slip-ons, on the other hand, are mainly used to customize the bike's appearance, but their cost and ease of installation are some major advantages. In both cases, sound quality can be enjoyed to the fullest.

    Full Exhaust


    ■The pipe thickness, shape, and merge method not only make for better performance, but also improve acceleration and other characteristics, which is useful for improving riding techniques.



    ■This is a type of aftermarket exhaust where only the silencer is replaced. Power and torque will not be improved as much as a full exhaust, but you can enjoy weight reduction and a change in looks.

    Q: What materials are available for exhausts?

    A: There are a variety of materials to choose from.

    In the past, steel (iron) was almost the only choice for exhausts, but in recent years, stainless steel exhaust pipes have become the norm for mid to large displacement bikes, and some 1000cc supersport models use titanium exhaust pipes. Aftermarket exhausts use mostly titanium or stainless steel exhaust pipes for performance-oriented sport models.

    For both the pipes and the silencer, titanium has the advantage in terms of lightness, and a wide range of surface treatments, such as heat coloring, are available. Incidentally, the harder the material of the exhaust pipe or silencer, the harder and higher the sound quality tends to be.

    Exhaust Pipes

    Stainless steel is strong, titanium has the advantage of overwhelming weight reduction, and both are resistant to rust. Steel (iron) pipes are also available, and are popular for classic bikes.


    ■Stainless Steel




    Titanium is mainstream, but stainless steel, aluminum, and carbon products are also available. In recent years, there are many unique designs, making it easy to show off your individuality.





    Q: Does an easy to install slip-on make a difference?

    A: The sound quality will change, and you may also experience weight reduction.

    It is true that you will get less change in performance than with a full exhaust because you are still using the stock exhaust pipes. However, if a product made of lightweight titanium material is used, the weight will be less than half of the stock silencer, so you may feel the lightness in handling. There are also many high-performance slip-on exhausts that can increase power and torque. Especially for small-displacement bikes with low original horsepower and torque, you will be able to feel the performance improvement even in your average daily riding.

    Q: Is it true that there are exhausts made by bending each one individually by hand?

    A: Methods vary by manufacturer.

    Most stock and aftermarket exhausts are made by bending pipes using a 2D bender. However, there are also aftermarket exhausts made with the traditional "hand bending" method, in which a craftsman bends a pipe filled with sand while searing it with a gas burner. Although there is a machine called a 3D bender that can perform continuous bending, few manufacturers use it because of its high degree of difficulty. Incidentally, there is little difference in performance between hand bending and machine bending if the products are made by the same manufacturer.


    ■Machine bent exhaust pipes have a uniform finish. When manufactured with a general 2D bender, straight sections are created between bends.


    ■Hand bending is a process in which pipes are seared with a burner and bent one by one. The continuous curves are beautiful, but can only be made by skilled craftsmen.

    For MotoGP machines titanium plates are curved and then welded


    ■Thin titanium sheets cut into strips are curved into a ring shape and welded together to form a pipe. The pipes can be freely made in any curve and diameter, but it is both time-consuming and costly.



    Webike Japan's global merchandiser who is passionate about motorcycles. Born in Japan, and spent his childhood in the US. 25 years of riding experience mainly on the tarmac and motorcycle market. He loves products made in Japan and considers himself a "Japan Parts evangelist".