O-ring sizes for 4 speed transmissions

Moto Guzzi V700, V7 Special, Ambassador, 850 GT, 850 GT California, Eldorado, and 850 California Police models

Updated: 

There is one O-ring used with the 4 speed transmissions: the O-ring for sealing the outer body of the throw out bearing assembly to the rear cover. There are two variations: one for 20 mm diameter outer bodies (early transmissions) and one for 22 mm diameter outer bodies (later transmissions).

O-ring to fit 20 mm diameter outer bodies

These measurements were made to the best of my ability (I do not know the original specification).

  • O-ring for the 20 mm diameter outer body of the throw out bearing assembly (MG# 90706150): 15.3 mm ID × 2.4 mm wide

A -113 x-ring of the following actual dimensions also works well (contributed by Tony Sciandra of Caffe Fresco Specialty Coffee Roaster on the old Yahoo! Loopframe_Guzzi news group (which has now moved to Groups.io)).

  • 0.549 inch ± 0.007 inch ID × 0.755 inch OD × 0.103 inch cross-section. Nominal dimensions are 916 inch ID × 34 inch OD × 332 inch cross-section.

This x-ring can be purchased from Precision Associates, part number 4444-113 or McMaster-Carr part number 90025K228.

O-ring to fit 22 mm diameter outer bodies

These measurements are accurate to the original specifications.

  • O-ring for the 22 mm diameter outer body of the throw out bearing assembly (MG# 90706170; OR 3068): 17.13 mm ID × 2.62 mm wide