Yamaha R3 Bored Throttle Bodies 2015/Current

Yamaha R3 Bored Throttle Bodies

Unlock stronger mid-range punch and top-end power on your Yamaha R3 with Spears Racing’s professionally bored throttle bodies. Starting with genuine OEM units, we precisely enlarge the bore diameter to allow substantially more air into the engine. The result is improved airflow, stronger torque, and higher horsepower throughout the rev range—with the most noticeable gains in the upper mid-range and at full throttle.

Our preparation is a careful, multi-step process tailored to each set of throttle bodies. Using CAD-designed tooling, we bore the bodies and fit custom throttle blades sized specifically to the new bore (rather than simply matching the original plate). Where beneficial, we reduce the shaft profile for less restriction, install low-profile button-head screws, mill the topside for optimal clearance, and finish with tumble polishing. These refinements can increase airflow by up to 15%.

Real-world horsepower gains depend on the rest of your setup, but most riders see roughly a 7–15% increase in rear-wheel horsepower when the bored throttle bodies are paired with complementary modifications. Because this is a direct bolt-on upgrade, you can retain your stock airbox or switch to individual velocity stacks/pods as you prefer.

After installation, proper setup is essential for best results and smooth running. Synchronize the throttle bodies, then re-calibrate the Throttle Position Sensor (TPS) so the ECU and any fuel controller receive accurate readings. Confirm that your fuel controller is zeroed and registers 100% at wide-open throttle before riding.

Whether you’re building a track-focused R3 or simply want a sharper, freer-breathing street machine, Spears Racing’s bored throttle bodies deliver measurable airflow and performance improvements while remaining a straightforward, reversible upgrade.