GU39103960 Locking fuel filler cap with 2 keys for most early Tonti frame Guzzis, including Convert, 850T, 850T3, LeMans I, LeMans II, late V7 Sport, 750S, S3. Some late Eldorado. This version was used as original on some California III and carbureted California 1100, as well as Ducati 600 Pantah. Sealing ring outer diameter is 48mm, measure the ring on your current cap to be sure this is the correct item for your application. Some very early models had a larger sealing surface diameter. Also references as part numbers 30103961 or 29736960 or 29736961 or 29103951 or 30103960 068483560
Similar caps were used on many Italian motorcycles including Ducati, MV, Laverda and Moto Morini during the 1970s. Be sure to measure the gasket outer diameter for these applications as well. Suitable as a replacement for non locking Ducati cap part number 068483560 fitting Ducati 350-500 Twin, Ducati 350-500 Twin GTV, Ducati 350-500 Twin Sport, Ducati 450 Desmo, Ducati 500 Sport Desmo, Ducati 750 GT/Sport, Ducati 750/900 SS, Ducati 860/900 GTS, Ducati 900 Darmah
Note: It is normal to have to fine tune the locking tab at the front of the fuel cap to optimize the engagement to your particular fuel tank. Be bending the tab slightly you can adjust the tension required to latch and unlatch the catch. This is accomplished quickly and easily with a flat blade screwdriver.