| Diagram | Fig. 5 — Gearbox: Shell, Gear Cluster, Mounting Bolts, Adjuster and Countershaft Sprockets · ref 25 |
| Subsystem | gearbox |
| Listed in parts books | 1975 |
Norton 'O' Ring
An 'O' ring from a Norton gearbox parts listing, sealing a shaft or spindle in the gearbox casing.
This is an 'O' ring listed in the gearbox section, showing up alongside the shell, gear cluster, sprocket, and mounting bolt in the parts book. It's a small sealing ring rather than a mechanical part in its own right, doing its job by sealing against a shaft or spindle passing through the gearbox casing to keep oil where it belongs.
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Our record on this one is thin - one catalog appearance, tied to 1975 in the books we have. The gearbox figure it sits in points at the shell and cluster area, so that's the neighborhood it works in, but we don't have more detail than that on the specific bore or shaft it seals.
This is a Norton part, not a Triumph one - it lands in Norton gearbox listings, so if you're cross-shopping with a Triumph parts book, don't assume this is your part. Give the shop a call and we'll confirm exactly where it goes before you order.
Sorry if we got something wrong here. If you think this information isn't correct, .

