| Also known as | E8770 |
| Diagram | Fig. 21 — FRONT WHEEL · ref 19 |
| Subsystem | wheels |
| Listed in parts books | 1971–1974, 1976–1980, 1983 |
Washer - disc/sprocket nut (.390"-.625"-.064")
Small flat washer (.390"-.625"-.064") used at wheel and top-end fixing points, PN 70-8770.
This is a flat washer, part number 70-8770, also seen in older records under E8770. The catalog dimensions given for it are .390 inch ID, .625 inch OD, and .064 inch thickness, which puts it in the small flat washer category used in a few different spots on the bike rather than being a single-purpose fastener.
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What makes this one worth stocking is how many places it turns up in the parts books - front wheel, rear wheel, rear wheel with the Smiths speedo drive box, rear wheel with the Veglia drive box, plus cylinder barrel and tappet block work, and the crankcase timing gear and oil filter area. It's a general-purpose washer that shows up wherever a nut or stud needs a bearing surface across those wheel and top-end jobs.
Given how many figures list it, it's a good one to keep a few of in a drawer - washers like this tend to get tossed, distorted, or lost during teardown and you don't want to be stuck at final assembly without one. The catalog spans 1971 to 1983 across its appearances, so it's been in service a long while under this number.
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