Bored out Koso 34mm Throttle Body to 37mm for Honda Grom 125! Super large throttle body that will allow your big bore engine to breathe!


Big bore engines for the Honda Grom 125 will require a larger throttle body so that your engine can perform and run optimally. Koso 37mm Throttle Body is the Largest available. Perfect for the displacement of 180cc and higher! Throttle body does not come with any sensors, so swapping over the sensors from the stock throttle body is required. Koso Large Intake Manifold is required, the 37mm throttle body will not work with OEM manifold.


SKU: KOSO-1033
  • This product is legal for closed-course competition use only; for racing vehicles (a competition vehicle not used on public highways). Intended for off-road use or race purposes; does not meet regulations of pollution controlled roads or highways. This system is NOT compliant with the California Environmental Protection Agency (E.P.A.) or California Air Resources Board (C.A.R.B) for use on public roads or lands.

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