Home > Dual Sport > Yamaha WR250X/R Parts > Modification Guide > WR250R Performance Guide

Off the showroom floor, the Yamaha WR250R/X is tuned more for fuel mileage and emissions, rather than performance. This makes the bike feel a little "corked up" or "anemic", but luckily there are a few things you can do about that.

To maximize performance and improve ride-ablity of your WR250R/X, we recommend that you do the following...
  • Install an EFI (Electronic Fuel Injection) Controller to adjust the bikes fueling
  • Replace the exhaust system with a lightweight free-flowing exhaust
  • Replace the stock air filter with hi-flo air filter
  • Remove the bikes EXUP motor/cables
  • Remove the bikes AIS - Air Induction System

  • Doing these simple things will give the bike a nice bump in performance, making it much more fun to ride, plus it'll sound better, and you'll drop a little bit of weight at the same time (the stock exhaust is kind of heavy). It will also help eliminate some of the bikes snatchy on/off throttle, which is a common complaint.



    An EFI (Electronic Fuel Injection) Controller is is HIGHLY recommend any time you want to improve the ride-ability and increase the power/torque of your stock WR250R/X, or whenever you install an aftermarket exhaust and/or air filter. This is a must-have mod for these bikes and will make them run much better whether you're running the stock exhaust or have added an aftermarket system.

    At this time, we offer two different EFI Controller options, the JD Jetting EFI Controller, or the Dynojet PowerCommander 6. Details below. Each are simple to install and plug into existing wiring using stock connectors and will get your bike running the way it should!

  • Yamaha WR250R JD Jetting EFI Controller

  • Yamaha WR250R Dynojet PowerCommander 6



    As of spring 2024, there are not many exhaust systems left in production for these bikes. We were just notified that FMF has discontinued their entire line of exhausts for the WR250R and will not be making more. This leaves Yoshimura as about the last company to be making an exhaust, their RS-4 Slip On muffler. See below...

    Where To Buy:
    We do not carry this product, but you can order it and other exhaust systems from one of our trusted partners/affiliates. If you make a purchase from them, we do receive a small portion of the sale, at no extra cost to you.

  • Yoshimura RS-4 Slip-On Muffler for WR250R at Motosport.com



    The exhaust systems outlined above will take care of the exhaust side of the equation, but while you're at it, most riders will also replace their bikes stock air filter with something that flows air better. On our WR250R and WR250X Project Bikes, we use the No Toil Super Flo Filter Kit, which was developed by No Toil to increase performance and improve throttle response. These kits are a complete replacement for the OEM WR250R/X Filter and Cage assembly. Included in the kit is a super-strong, high density polymer filter cage with no backfire screen that will allow you the maximum amount of air to flow freely to the intake. You also get a top quality, two-stage, flame retardant, pre-oiled foam air filter. The foam is specially treated to extinguish flames and sparks, so this filter won't burn.

  • Yamaha WR250R No Toil Super Flo Filter Kit


    EXUP Servo Emulator **
    When you remove the OEM Yamaha WR250R/X muffler, you will also be removing the EXUP cables and motor that are attached to the exhaust. This is a simple task, and involves un-plugging the EXUP Servo motor. 12oClockLabs offers an EXUP Servo Emulator, which plugs right in so you're bikes computer won't realize you've removed anything. This part is highly recommended anytime you remove the OEM exhaust.

  • EXUP Servo Emulator at 12oClockLabs.com

  • EXUP Servo Emulator at GraveSport.com

    AIS Block Off Kit **
    When installing an aftermarket exhaust on your WR250R/X, the AIS (Air Induction System) is no longer serving any purpose and will cause backfiring/popping on deceleration. Once you remove the AIS from the bike, this kit can be used to block off the port/hose on the bike.
  • AIS Block Off Kit at Gravesport.com

  • ** NOTE: Removing the EXUP system and doing the AIS kit are highly recommended if you replace the stock exhaust with an aftermarket system. You can still do each of these though, even if you leave your stock exhaust on. We have seen some customers remove the EXUP motor and cables while still using the stock exhaust, and then install the EXUP emulator so they don't get a CEL. When you do this, the valve inside the mid pipe will stay open.

    WARNING! - Motor sports can be extremely dangerous, injury or death can occur. No warranty is made or implied regarding any product sold by Devo Tech, Inc. / SoloRacer.com to protect users from injury or death. The user assumes all risks. Please read the rest of our Legal Disclaimer before ordering.

    Our on-line store is up and running 24 hours a day, 7 days a week. We use Yahoo! Secure Servers for all transactions so you can shop with complete confidence. If you are uncomfortable ordering online, call or email us for more ordering options.
    SRmoto.com |  Corbeau USA
    ©Copyright 2002-2024 by Devo Tech, Inc.