| Also known as | E3978 |
| Diagram | Fig. 14 — CHAINCASE AND ALTERNATOR · ref 7 |
| Subsystem | primary |
| Listed in parts books | 1960–1962 |
Adaptor ring
Adaptor ring for the primary chaincase and alternator assembly, Triumph PN 70-3978 (also E3978).
This is the adaptor ring listed under Triumph part number 70-3978, also known by its earlier E3978 designation. It shows up in the parts book under the chaincase and alternator figure, which puts it inside the primary drive area, working alongside the alternator setup.
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An adaptor ring like this one is used to take up a fit difference between two components in an assembly, in this case somewhere in the chaincase and alternator arrangement. Beyond that, our catalog entry for this one is brief.
If you're trying to match this up to your bike, give us a call and we'll confirm fitment before you order.
We've never carried this one. Tell us what you're after and we'll go looking — you'll get a price and photos before you commit to anything.
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