Conversion tips exhaust systems

Table of contents

Conversion tips exhaust systems
Hanselmann

Conversion tips exhaust systems

Conversion tips exhaust systems

Conversion tips exhaust systems

Conversion tips exhaust systems

8th pictures

Conversion tips exhaust systems
Debus

1/8
In principle, there are two options when the exhaust is to be replaced. Here is a completely new system from Akrapovic, from the outlets on the cylinder head to the silencer end cap.

Conversion tips exhaust systems
mps photo studio

2/8
On the other hand, there are so-called slip-on solutions like this one from Termignoni.

Conversion tips exhaust systems
Hertler

3/8
With older exhaust systems, slip-on solutions still work very well in terms of performance.

Conversion tips exhaust systems
Lohse

4/8
The E number must necessarily match the vehicle type, otherwise the exhaust is illegal even with a number.

Conversion tips exhaust systems
Hanselmann

5/8
Systems without a dB killer are no longer allowed to appear off the racetrack.

Conversion tips exhaust systems
Schroter

6/8
Dieter Wolter from Bodis: “Modern systems with a front silencer also leave delicate slip-ons in the plug & Play without reducing performance significantly.”

Conversion tips exhaust systems
archive

7/8
The Bodis manifold of the Triple without Kat is purely for the racetrack.

Conversion tips exhaust systems
archive

8/8
The delicate slip-on is street legal and works well in terms of performance thanks to the large front silencer of the current Triple.

counselor

technology & future

Conversion tips exhaust systems

Conversion tips exhaust systems
Optics, sound, performance

Content of

Exhaust systems are big business and big business. Better optics, fat sound and increased performance arouse desires. PS explains what to watch out for.

Uwe Seitz

06/17/2014

Anyone who lends a hand on motorcycles out of the box today is going deep into the jungle of paragraphs. And easily perish in it if he walks too naively into it. This is probably no more the case for any component on a motorcycle than for the exhaust – according to a horsepower survey on our Facebook page, it is right at the top of our readers’ conversion wish list.

Buy complete article

Conversion tips exhaust systems

Conversion tips exhaust systems
Optics, sound, performance

6 pages) as PDF

€ 2.00

Buy now

The last piece of motorcycle that has to overcome the burnt mixture is under close scrutiny by law enforcement officers because this is where the music is made, and it is well known that not everyone likes it. In addition, there are emission values ​​- that is, how much “dirt” comes out of the back. Such thumbscrews have at least an aesthetic influence on exhaust systems on production bikes and make large technical solutions with complex technology such as flap systems and huge front silencers necessary. The cost pressure in large-scale production does the rest.

Factory compromises

In recent years, therefore, various trends in series systems have been identified, which have been massively influenced by the tougher conditions. The exhaust designs on the right-hand side, which had been common for decades, grew into gigantic pipes or adventurously angular boxes. The manufacturers therefore initially developed double end pots that went under the bench, especially among athletes. Until these too became unsightly large. The Yamaha R1 is a prime example of this. At the moment, athletes in particular are making the journey to the stub end pot consisting of a large front silencer with a catalytic converter and flap systems such as on the S 1000 RR, Fireblade or the Panigale. What they all have in common is the pursuit of the largest possible volume for good performance and low noise levels for homologation with optical compatibility.

Which is still not always successful, especially optically. This is precisely why most sporty-minded motorcyclists want to swap the often coarsely or strangely shaped “series bags” for better-looking, sounding and – if possible – performance-enhancing accessories. At first, points in Flensburg are only immune to those who are either exclusively on the racetrack or who buy approved parts.

Buy exhaust system on markt.motorradonline.de

Conversion tips exhaust systems

Exhaust & silencer


Product test: exhaust systems for the Kawasaki Z 1000


Accessory silencer for Kawasaki’s naked bike


read more

Complete system or slip-on solution?

In principle, there are two options when the exhaust is to be replaced. In addition to a completely new system that extends from the outlets on the cylinder head to the silencer end cap, there are so-called slip-on solutions. The customer gets an alternative to the always particularly eye-catching rear silencer. The series counterpart is dismantled and the accessory is simply pushed over the open tube (slip on). “When it comes to optics and sound, slip-ons are the most practical solution,” explains Dieter Wolter from Bodis. “When it comes to sound, the accessory manufacturers move within the legally permitted tolerance of five percent to the registered noise of the series system.” And that’s a lot when you know that the volume, measured in dB (decibels), increases progressively in relation to the value. A series system homologated with 95 dB can therefore be equipped with a slip-on rear silencer until almost 100 dB are reached.

The legislature must allow tolerances due to possible measurement inaccuracies, as is also done with radar systems. For example, the point in time of the measurement is not insignificant, Wolter knows: “If the measurement is taken after a rain shower, when there is a lot of oxygen in the air and the mixture consequently burns harder, one decibel more is quite possible.”

Slip-ons should have sufficient volume

In order to avoid any problems from the outset, manufacturers also leave a few percent buffer. “At Bodis, we stick to around 40 percent of what is allowed with our end pots,” explains Dieter Wolter. “Although the systems don’t actually get louder with age, because more heat-resistant ceramic fibers are used as insulating material and the silencer no longer gets sooty as it used to be due to inaccurate carburetor settings.”

Of course, slip-ons are also significantly cheaper than a complete system. However, hopes that are too high with regard to an increase in performance are not appropriate. In 2012, PS tested and measured all common slip-ons for the BMW S 1000 RR. With none of the retrofit silencers did the superbike achieve the same level of performance as the standard system. With two horsepower less, the BOS Superbike achieved the best result.

“On older motorcycles with serial manifolds without a catalytic converter, slip-ons still work quite well in terms of top performance,” says Armand Mottier from Micron Systems in Furth. “Of course, the slip-on mufflers should have sufficient volume. With dB-Killer, delicate mufflers are therefore real performance killers. In the low-priced segment, stuffing is often done mercilessly in order to achieve the required noise levels. “

A small, short muffler is certainly the ideal of beauty, but unfortunately it can only be homologated quietly with sophisticated technology. Since the same applies physically to retrofit slip-ons as to series systems, when buying a product, one is often faced with the decision: performance or a cool look with a great sound? This is particularly true for systems (with or without a catalytic converter) where there is only the rear silencer on the manifold.


Conversion tips exhaust systems


archive

The delicate slip-on is street legal and works well in terms of performance thanks to the large front silencer of the current Triple.

However, this does not apply to new systems with pre-silencers under the engine. Since the front silencer takes over some of the noise destruction in these systems, everything that comes afterwards can also be smaller in volume without significantly losing performance. Basically, the external shape of the damper or its size is not decisive for the performance. As long as nothing is in the gas flow (dB killer), it works. Only then not legally on the street.

The situation is different for complete systems with a manifold – not just in terms of price. With regard to a complete system, you should pay attention to a cat in the manifold system for most motorcycle models with first registration from 2006 if the bike is to legally be on the road. It makes no difference whether the system would meet the emissions standard even without a catalytic converter. “Complete systems are rather uncommon for the road, if only because of the high costs,” Wolter limits their meaning, “because in the end it is a real increase in performance.”

Basically, the following applies: The damper volume cannot be replaced by anything. The volume guarantees good performance with moderate noise. An extremely small muffler quickly costs a few horsepower, as the exhaust back pressure can be relatively high. This means that with today’s valve overlap, the four-stroke engine is pushed back into the cylinder head under the exhaust gas back pressure, not only unburned, but also burned mixture, which has a correspondingly negative impact on the throttle response and power output.

The tuner can help here. “By appropriately adjusting the mixture composition, you can regain one or the other lost horsepower,” explains Mottier, but restricts: “As far as the gas throughput allows it.” If the damper is open, such problems occur less, but good injection optimization is basically a step in the right direction. But be careful: Open systems are illegal on normal roads.

Street, street and racetrack, racetrack only?

When processing, you should pay attention to the fewest possible connections with clamps. Turned flanges ensure tight plug connections even with frequent dismantling. A welding socket for the use of a lambda probe should definitely be available. Preferably with an M 18 x 1.5 thread; an adapter can be used for smaller probes. Such a connection in each manifold is particularly useful in two-cylinder systems in order to be able to tune each individual cylinder if necessary.

An important question for the purchase decision is of course the use. Should the motorcycle be driven on the road, on the road and on the racetrack or exclusively on the racetrack? This not only affects the problem with the homologated noise, although race tracks – especially in Germany – have increasingly stringent noise regulations. Even more, increase in performance and then saved pounds are important. “For sports use, a good, open silencer is part of the basic tuning,” says Mottier. Together with a sensible set-up, this is the first step towards increased performance. However, since noise is becoming a problem on more and more racetracks, you should orient yourself to the routes that you want to drive frequently. Unfortunately, the measurement methods are quite different because there are different requirements and measurements are made with different degrees of rigor. Unfortunately, this often turns things into a game of chance.

In the case of complete systems, the manifold system is the best way to influence the performance characteristics. Manifold systems for sports use are usually designed for extreme top performance. The rule of thumb “large pipe diameter promotes performance, moderate diameter rather the torque” falls a little short of the mark. “This is how you operate behind the manifold,” explains Wolter. “You try to get a narrow diameter at the manifold directly on the cylinder head, because the burned mixture is quickly transported away – like a garden hose: If it is narrower, the water flows faster.” The total length of the system also determines the power and torque, why there are sometimes impressively winding exhaust systems.

The air filter and airbox are also significant

Only a few manufacturers succeed in perfectly combining both parameters through extensive development work. An experienced tuner can find a good compromise by setting it up accordingly, which also enables a clean throttle response with significantly increased peak performance. The real potential of an exhaust system only comes into play when the mixture is right. Last but not least, the air filter and the airbox are also important here. Where a lot comes out, a lot has to go in!

Of course, titanium brings significant weight advantages, especially with the manifold systems, compared to the stainless steel otherwise used – but this is many times more expensive. It is much cheaper to save weight elsewhere on the motorcycle. Unless you’ve radically reduced everything else, like on a Ducati Superleggera. But money doesn’t play such a big role here, as it usually does with racing motorcycles for the big competition in the Superbike World Championship, for example. After all, this is a rather negligible field for normal mortals.


Conversion tips exhaust systems


Lohse

The E number must necessarily match the vehicle type, otherwise the exhaust is illegal even with a number.

Number is not the same as number

Approved exhaust systems have a corresponding stamped marking, the so-called E number. But be careful: not every exhaust with this number is approved. Exhausts are homologated on certain motorcycles. The number shown is assigned to this. So if an exhaust X is homologated for a Kawasaki ZX-10R, for example, it is only approved for this motorcycle. But anyone who screws this exhaust to a Suzuki GSX-R 1000 is violating the approval regulations despite the E number on the exhaust. Police officers cannot easily access the huge database of these E-numbers during checks and the corresponding proof is not mandatory according to the letters of the law, but it helps immensely in the event of a control and the HU. It is usually included with the purchase of the appropriate branded accessory damper.

It is also important to ensure that a catalytic converter in the standard silencer can also be found in the retrofit silencer and that it is included in the operating permit. DB killers must be installed in public transport. If you are caught without, in the best case you can get away with it for 20 euros because of improper noise behavior, but usually there is a threat of a complaint for driving without an operating permit, since the dB eater is listed in the road traffic licensing regulations.

Development work


Conversion tips exhaust systems


archive

The Bodis manifold of the Triple without Kat is purely for the racetrack.

Racing manifold for T-Cup Streety

Dieter Wolter’s Bodis team spent four months developing the exhaust system for the racing version of the Triumph Street Triple. “With a system, you normally start with a blank sheet of paper and start at the front of the manifold. Finally, there is the damper, because its position, length and so on have a significant impact on the result, ”explains Wolter. The problem this time: The slip-on manifold was already part of the accessories, which determined its length and position. “Since you cannot simply calculate the ideal moment for the perfect exhaust gas backflow, we had to try a lot on the test bench, experimenting with pipe diameters and other parameters,” continues Wolter.

If you don’t have enough experience and invaluable knowledge, you won’t be able to do it in four months. In the end, the boys of the Street Triple were able to elicit almost six more horsepower more peak power in racing trim. The manifold is not approved for use on the road. “That would have paid off even less with Kat and the time-consuming approval process, as we cannot recoup the development costs for such a part anyway. There aren’t enough races in the Street Triple for that, ”says Wolter. The manifold is sold by the Triumph specialist SBF (www.triumph-sbf.de), which also has the Bodis slip-on in its range.

Leave a Reply

Your email address will not be published.