If the inner diameter of the carburetor funnel (air inlet) is smaller than about 1.6 inches (40 mm), the synchrometer cannot be measured alone.
In that case, you can combine the original optional small diameter adapter to make the measurement possible.
Due to the nature of this product, the rubber material on the surface may get black stained after the first time it is used.
In addition, there may be some scratches or dents on the manufacturing method, so please rest assured that there is no problem with the use and measuring process.