Engine Services: DR-Z400S/SM


The DR-Z400SM has been the surprise of the motorcycle industry these last several years. Suzuki created a winner combining a fun-factor that is through the roof with great styling and a low price point. It also just so happens that Yoshimura has a ton of experience with this motorcycle, and offers a full line of products and engine services for the DR-Z400 Family.

Available Services:

  • Machine Gasket Surfaces
  • Mill head to increase compression ratio
  • Inspection and Reassembly of Top-end
  • Complete Bottom-end assembly
  • Port and Polish Head
  • ISF Transmission Process
  • Knife-edge and Balance Crankshaft
  • Complete Race-Spec Build for all classes
  • Installation of High Performance Engine Components
    • Camshafts
    • Connecting Rod
    • Piston
    • Valvetrain Components
For Further Information On Yoshimura Engine Services, Please Call Our Sales Department at (800) 634-9166


RS-4 Exhaust Systems

The RS-4 Twin Pipe kit was previously only available as a custom system for Kevin Schwantz who was passionate about these pipes on his Super Motard bike. He wanted his bike to look like a "Hot Rod" and have a "cool" factor. We obliged and one of our most sought-after-yet-unobtainable pipes was created, which, up to now, was not available to the general public. Yoshimura is offering these incredible “Twice Pipes” which are completely fabricated by hand and TIG welded to perfection. They certainly sit at the high end of what is available for the mighty SM... but that's what Kevin wanted! The pipes have a stainless steel header and Y-pipe mated to twin carbon fiber RS-4 mufflers for incredible looks and performance. The kit also comes with a custom Yoshimura kick-stand.

Application: DR-Z400SM

Carbon Fiber


RS-2 Exhaust System

The RS-2 is a great all around pipe. It has good ground clearance, is lightweight, gives you big power gains and looks really good. Plus, it comes with all the nice little touches and features that make Yoshimura famous. The plasma cut heat shield with our Yoshimura logo, high quality exhaust springs and even spring vibration dampers with the Yoshimura logo molded in.

Application: DR-Z400S/SM

Carbon Fiber


MJN Carburetor for DR-Z400SM/S

New for the DR-Z400 is Yoshimura's MJN Carburetor System. The MJN nozzle controls the amount of fuel in proportion to the throttle opening (intake air) by accurately drilled and positioned fuel intake jet orifices. This results in more efficiently atomized fuel, and gives better throttle response as well as better fuel efficiency overall. Also, the MJN system supplies the fuel through the MJN nozzle in the center of the bore where air speed is the fastest. This atomizes fuel even better!

Another very important benefit of the MJN system is when the throttle is shut off and engine braking occurs, a very minimal amount of fuel is guided into the intake ports. Therefore, remarkably crisp throttle response is obtained, upon corner exit and transition back to 100% throttle settings.

Application: DR-Z400S/SM
Carburetor Model: TMR-MJN4
Part #: 798-126-2910
MSRP: Call to Order - (800) 634-9166

Required Parts:

  • Yoshimura Throttle Housing Set (Pictured)
  • Coolant Reservior Tank Stay (Part #: 761-125-0300)
  • Insulator Hose Band (Suzuki Factory Part)
    *Incase of removed air filter:
    Intake Part #: 13111-29F00
    Carb Part #: 09402-58208


Part#: 671-010-8500
(Black Throttle Housing)
Part#: 671-010R8500
(Red Throttle Housing)


BMC Air Filter

These filters are made from the best materials, designed by top flight engineers, and represent the cost of victory in modern day racing. BMC filters offer maximum protection from dirt and debris entering your engine through the airbox. The filters also offer up superior air-flow for increased power at all RPM levels. BMC filters are washable and feature close tolerances, maximum filtration area, and long lasting durability.

Factory-style Replacement Filter
Part #: 761-424-08
MSRP: Call to Order - (800) 634-9166

*Compatible with Yoshimura MJN or Factory Carburetor



Oil Breather Tank Kit

If you plan on taking your SM all the way, then you'll definitely need this. It not only looks ridiculously trick, it is! This Oil Breather tank is necessary when using with the BMC Funnel Filter, but it can also be used as a stand-alone unit.

Application: DR-Z400SM
Part #: 532-001-0000
MSRP: Call to order - (800) 634-9166