| Also known as | E3821 |
| Diagram | Fig. 15 — CHAINCASE AND CHAINS · ref 4 |
| Subsystem | primary |
| Listed in parts books | 1964–1971, 1974, 1976–1980, 1983, 1985 |
Countersunk screw
A countersunk screw used as an inner plate fixing in the chaincase/crankcase area, part number 70-3821.
This is a countersunk screw, PN 70-3821, that shows up repeatedly in the chaincase and crankcase sections of the parts books. The grounding info we have on it points to it being used as an inner plate fixing screw — the kind of small fastener that holds an inner cover or plate flush against the case so nothing snags on the primary chain or crankcase innards.
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It's cataloged under the older E3821 form as well as 9998-393, so if you're working from an early parts book or a different index you may see it listed under either of those numbers instead of 70-3821. All three point to the same physical screw.
With 31 appearances across the catalog spanning 1964 to 1985, this is a long-running fastener that turns up across a wide swath of chaincase and crankcase assemblies. We don't have a specific model or year pinned to any one appearance, so if you're chasing an exact fitment for your build, give us a call and we'll confirm it against your parts book before you order.
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