| Also known as | 18-89100C, E6840 |
| Diagram | Fig. 1 — CRANKSHAFT AND CONNECTING RODS · ref 14 |
| Subsystem | engine bottom |
| Listed in parts books | 1969–1974 |
CIRCLIP,T150,BSA A7/A75
A circlip, PN 70-6840, listed for the T150 triple and BSA A7/A75 models.
This is a circlip listed under Triumph part number 70-6840, also known by the earlier form 18-89100C. The catalog description ties it to the T150 triple as well as BSA A7 and A75 models, and one of our other catalog references calls it out as a piston circlip used across triple and Norton applications.
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A circlip like this one is a small retaining ring that seats in a machined groove to hold a component in place axially, commonly used at the ends of a piston's gudgeon pin bore to keep the pin from working sideways and scoring the cylinder wall. We don't have more detail on this one beyond what's in the catalog record.
Given the cross-model listing, double check which bike and cylinder you're working on before ordering, and call the shop if you want us to confirm fitment first.
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