Dr. Jekill & Mr. Hyde presents the Twenty-One - Dr. Jekill & Mr. Hyde | Electronically adjustable exhaust for motorcycles | Best sound | Street legal
19 Nov '20 Dr. Jekill & Mr. Hyde | News

Project 21: 2-in-1 clubstyle/performance exhaust

News, Press, Harley-Davidson

The 'Twenty-One' 2-in-1 clubstyle / performance exhaust from Dr. Jekill & Mr. Hyde is ready to be mounted on your bike! As of now we start delivering this electronically adjustable exhaust system that takes the Milwaukee-Eight Softail models to the next level.


With scorching power, the 'Twenty-One' makes the Milwaukee-Eight Softails models into raging powercruisers that are ready to take on the road! Check out the video below and see what the 'Twenty-One' is capable of. 

twenty-one 2in1 exhaust

The ‘Twenty-One’ contains a sound that really brings the power of the M8 engine to new heights, in ways you'd never expected. The thrill of driving is enhanced by a brighter feedback from your exhaust, challenging you to demand that little bit extra from your bike. The exhaust has been subjected to extensive sound tests to create this perfect sound experience.

When you choose to ride a Twenty-One you get a full exhaust system with a header set and muffler. Where all other Dr. Jekill & Mr. Hyde exhausts are very clean, we have opted for a rough and unpolished look with this one, including visible welds and discoloring over time. The system is lighter than standard systems, has optimal ground clearance so you can hang comfortably in the bends. But despite the rough and raw look, it matches the quality you are used to from Dr. Jekill & Mr. Hyde.

twenty-one 2in1 exhaust

For the clubstyle rider performance is of great importance, so this has been taken into account massively in the development of the Twenty-One exhaust. Within the legally permitted standards of course, the Twenty-One significantly increases the performance of your bike. Thanks to the design of the exhaust, there is no loss in performance while riding with a closed valve. This ensures a safe and smooth riding experience, regardless of the mode you ride in

Dr. Jekill & Mr. Hyde | The Exhaust is a completely street legal system and complies with European legislation and laws, as well as being EC/ECE/EG/ABE/ EEC/EU/ECE/EGBE and TÜV tested. So in short: your riding style might get you in trouble… your exhaust won't!

twenty-one 2in1 exhaust

The Twenty-One is customizable. For the muffler and header set you can choose between a black and brushed edition, with a slashcut or streetfighter end cap in black, alu or bronze. The header sets can be equipped with a full cover of shields or a minimal cover. Visit our exhaust configurator to see what design fits you best. 

What the experts say

Deep, rumbling and powerful... As soon as Mr. Hyde is unleashed the Twenty-One gives you the perfect roaring soundtrack when you are riding your bike at full throttle. But don't take our word for it; let's see what the experts have to say about our new exhaust.

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