Looking for a little more pulling power out of your 2024-2026 Yamaha YZ250F without busting inside of your engine? Andrew Flores, the head of RT Engine R&D, has developed an airboot for the 2024-2026 YZ250F that improves power by 4% on the dyno. As you may know this is more than going from pump gas to very expensive, hi-performance, oxygenated race fuel. Race Tech invested thousands of hours in development using sophisticated “Airflow Analysis Software” in conjunction with their custom Digital Flow Bench, Engine Chassis Dyno, and Track Testing. This airboot is produced using the latest 3D printing technology and materials. Race Tech is using a flexible material where the boot mounts to the throttle body and a more rigid but still flexible material for the rest. This is designed to snap into the stock air boot mounting ring but you will need to swap over your air temp sensor.
Over 30 prototypes were created before finalization, which is music to any test rider’s ears. The airboot is best used in conjunction with a Vortex ECU, but we did try it with the stock ECU as well. Improved airflow works best with matching fuel but we have a map that you can use in conjunction with Race Tech’s Hi Performance Airboot. The stock airbox cover must also be modified. This is a popular modification. Note that the 4% increase does not include the cover mod on the dyno.
CFD (Computational Fluid Dynamics) Simulations and Flow Bench analysis show Race Tech’s airboot flows more air and has more air speed than both the stock YZ250F and 450F airboot. The design uses a composite of two types of flexible polyurethane and is sold as a functional prototype. I have over 20 hours on the RT airboot with no issues.
With all this being said, what did this Race Tech airboot do? In simple terms it gave our 2025 YZ250F some of that older style 2022 torque feel out of corners and gave the Yamaha a healthier mid range pulling power. What I noticed most is that I can pull second gear a little longer and there is added “meat” (or torque) when accelerating out of deep ruts. The stock 2025/2026 YZ250F has to be shifted A LOT because the engine character has a freer feel so that means it runs through the rev range quickly (we can this spool up). The older gen YZ250F has more torque feel and doesn’t have as quick of spool up as the newer gen YZ250F and this airboot gives me some of that older torque feeling out of corners. This is all with the stock ECU and our map (shown below).
With the Vortex installed, you will get added low end and more top end/over-rev than you do with the stock ECU. For $450.00 this is part you can bolt on and feel (half of the cost of a muffler system that will not make as much horsepower as this part). I walk around and do these factory bike videos at Monster Energy Supercross rounds and the number one thing that Yamaha teams DO NOT want me to look at or talk about is the airbox on their YZ250Fs. There is a ton of hidden horsepower inside the airbox/intake area and Race Tech is giving you some of that hidden horsepower for your YZ250F right here. If you’re looking to get some torque as well as mid range pulling power back into your YZ250F this is a good buy in my opinion.
