Partial load or half gas can be reached when the gas slide valve is 1/4 to 3/4 open. Jet needles and mix tube are responsible for regulating the mix in this area. If the engine splutters (too lean), 4-strokes (too rich) or ‚chokes‘ on acceleration, the mixer tube and/or jet needle have to be adjusted accordingly.

We stock DELL'ORTO mixer tubes for the PHB 28 to 30 from AV 260 (lean) to AS 274 (rich). The long version of the mixer tube is designated with AS. Its end section extends further into the intake range of the carburettor and makes the mix leaner with low thrott- le opening and on accelerating. The version with the short upper end piece enriches the mix, however, and is designated with AV.

We also stock DELL'ORTO mixer tubes for the VHS range in a number of different versions from very rich to very lean. Please note: The mixer tubes for the different types of VHS carburettors are not interchangeable. Pay close attention to the product designation when you place your order.

Conclusion: Indispensable for carburettor tuning in the partial load range.