Weber DCOE Needle Valve

These needle valves fit Weber 40, 45. 48, 50, and 55 DCOE or DCO carburetors. Carburetors that spontaneously begin to run too rich and don't seem to respond to resetting the float level may have worn needle tips that let too much fuel in. Each set includes one needle and seat, enough for one carburetor.

The needle valve size determines how quickly fuel can enter fhe float bowl when the float level drops. A larger number will allow fuel in more quickly. Note that you can go too large -- a too-large needle valve can allow fuel in so quickly that the float can't close soon enough to prevent a momentarily rich mixture.

Suggested sizes, based on individual cylinder displacement (assuming one throat per cylinder):
Up to 300cc per cylinder: 150
Up to 400cc per cylinder: 175
Up to 500cc per cylinder: 200
Up to 700cc per cylinder: 250
Over 700cc per cylinder: 300

These sizes are the recommended starting point for all DCOE carburetors, regardless of size. For example, a 1600cc 4-cylinder engine running dual 45 DCOEs should start with the 175 size. A 2-liter 4-cylinder engine with dual 40 DCOEs would use the 200 size. A 4.2-liter 6-cylinder running triple 50 DCOs would run the 250 size.