GU17114450 Pair of velocity stacks for VHB 29mm and 30mm carburetor equipped bikes. Aluminum replica of the original equipment "air funnel" for 30mm carbs as used on I Convert, 850T3, V1000 G5, 1000 SP, and CX100 LeMans, also fits VHB 29 carbs as used on Ambassador, 1969-1971 V750 Special, Eldorado, 850GT or the VHB 30 carbs on V7 Sport and 850T. Stack threads directly into carburetor body. Inside tapers from ~36mm to ~30mm at the carburetor entrance. By creating a more laminar intake air flow, these significantly improve throttle response throughout the RPM range, particularly in the middle and upper range. Use these with clamp on pod filters such as the K&N RU2450, or the one piece MG2640. When mounted properly, the velocity stack is nearly fully contained inside the air filter. Sold as a pair.