Frequently Asked Questions

What is a Dr. Jekill & Mr. Hyde system?
A Dr. Jekill & Mr. Hyde system is an electronically adjustable exhaust system that is 100% street legal.

For which brands is a Dr. Jekill & Mr. Hyde system available?
The exhaust systems are available for the following brands: Harley Davidson, Indian, BMW, KTM, Victory, Suzuki and Honda. In our configurator you can check if there is an exhaust available for your specific model.

How does the system work?
Our system has a valve that you can control with the mode switch. The valve will guide the exhaust gasses through different cambers. Thus creating the Dr. Jekill or Mr Hyde sound.
Watch the airflow movie on our page "Our Technique".

What does the European Type approval mean?
Our exhaust systems are tested and developed following the highest European standards and guidelines. Our systems are compliant with the highest obligatory standards in:
-    Emission
-    Sound levels (decibel)
-    Performance
This means that it is a fully street legal system and that it is compliant with the European legislation and laws.

Do I need to get a separate type approval once I have a Dr. Jekill & Mr. Hyde on my motorcycle?
No. Once you have purchased a Dr. Jekill & Mr. Hyde exhaust system you will receive a type approval card which matches the number on your exhaust system. The number on the type approval card also corresponds with the motorcycle number in your papers.

Is it necessary to tune my motorcycle when installing a Dr. Jekill & Mr. Hyde exhaust system?
We advise you to check at your local dealer what kind of options you have. In most cases it is not necessary but sometimes it is better for the overall riding experience. Exhaust, air intake and fuel are the 3 elements that are connected, if you change 2 out of 3 it’s necessary to change the 3rd one as well. This check is highly recommend when other non-original parts are installed on the bike.

Do I lose performance when I drive with a closed valve?
When the valve is closed you will not  lose performance and when the valve is opened an increase in performance of +/- 5% is realized. (This May differ per motorcycle brand and/or model). When you have a tuned motorcycle the increase in performance can be up to 15-20%.  Note; when you start tuning the difference in valve close and open will become bigger.

What is the difference between the Blackbox and Smartbox option?
The Blackbox system: Is a Dr. Jekill & Mr. Hyde control system which fits on Harley Davidson, Victory and Honda motorcycles
The Blackbox has two different modes:
1) Automatic Mode (Valve is controlled by the motor management, speed controlled)
2) Closed mode (Valve is closed at all times)

The Smartbox 2 system: Is a Dr. Jekill & Mr. Hyde operating systems which fits only on Can-bus models for the following brands. Harley Davidson, Indian, BMW and KTM.

The Dr. Jekill personality | Closed valve    
•    Dr. Jekill reflects the silent sound mode when our exhaust valve is closed, redirecting the exhaust gasses through our specifically designed exhaust chambers that not only damp the sound, but also allow a stable back pressure suitable to the engine.

The Mr. Hyde personality | Opened valve
•    Mr. Hyde reveals itself once our exhaust valve is opened by a touch of a button; the exhaust flow changes from the gasses being redirected into a direct flow straight through. The exhaust chambers then reveal their primary purpose of adding acoustics to the sound in open mode

Can I install a Dr. Jekill & Mr. Hyde system myself?
We strive to maintain the high quality for the riders, there for you can only buy our system at official dealers with certified mechanics who have been trained by the Jekill and Hyde Company. This way we can ensure the quality of the installation and the functioning of the exhaust. There are exceptions like in the USA. You can find our dealer network on our website.

Do the different endcaps provide a different sound?
The sound of our system is for 90% created by the damper, so the endcap has a minimal influence on the actual sound of the exhaust system. An endcap can be easily exchanged for a different design.

Is it possible to buy an exhaust system for a motorcycle that is not yet in the product range of the Jekill and Hyde Company?
The Jekill and Hyde Company is continuously expanding her product range. If our exhaust systems are not yet available for your motorcycle brand and or model you can keep yourself up to date about our product developments by keeping yourself informed through our website.

Where can I buy a Dr. Jekill & Mr. Hyde exhaust system?
You can buy a Dr. Jekill & Mr. Hyde exhaust system through our extensive dealer network. For more information on where you can buy a system: visit our dealer locator. If you cannot find a dealer near you, please contact The Jekill and Hyde Company at

Questions about warranty?
Please contact our warranty department at:

Does a Dr. Jekill & Mr. Hyde system needs to be maintained?
The only maintenance you need to do on your Dr. Jekill & Mr. Hyde exhaust system is the cleaning of the exhaust like you would do on your original motorcycle exhaust system. No special maintenance is required for a Dr. Jekill & Mr. Hyde exhaust.

How Should I clean my exhaust?
Al our exhaust are made from stainless steel, this doesn’t mean you don’t have to treat your surface. It’s important to maintain your exhaust surface to keep it in a mint condition.
•    For chrome use first of all warm water to wash the sand off, after you can use chrome cleaner to clean and protect the chrome.
•    For black and other systems use first of all warm water to wash the sand off , warm water with a clean soft towel.

Note: never clean they exhaust when it’s hot!

How do I know how many dBa my bike could produce?
Each bike has a type sticker on the frame of the bike, on this sticker you will find the dBa level connected with a RPM number. The Dr. Jekill and Mr. Hyde system will have the same dBa level on that certain RPM number.

Do I have a Can-bus bike or not?
Can-bus is a way of communication on the bike Can (controlled area network) this make it possible to work with the modern features.  From the outside it is not always possible to recognize if it is a Can-bus bike. When you go to our configurator and select your bike and model year it will automatically show you if it will work with or without Can-bus. After this, the possible(s) systems will appear.

Header heat tape:
When you use tape on the headers it will protect the rider for extreme header temperatures, this heat will be guided down the pipe in to the exhaust. Since this can lead to extreme temperatures that could lead to failures in regard to the surface of the exhaust. Extraordinary heating is not our responsibility and thus taping your headers will terminate your warranty.