| Diagram | Fig. 3 — CRANKCASE · ref 85 |
| Subsystem | engine bottom |
| Listed in parts books | 1969–1970 |
BSA Bolt, crankcase (5/16" Unified Coarse x 1 1/2")
A 5/16 inch UNC crankcase bolt, 1 1/2 inches long, used to hold crankcase halves together.
This is a crankcase bolt, 5/16 inch Unified Coarse thread, 1 1/2 inches long. The catalog places it in the crankcase figure, so it's one of the fasteners holding the crankcase halves together at the bottom of the motor.
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The catalog record shows this bolt appearing across entries from 1969 to 1970, but it doesn't spell out which specific model or engine family it was fitted to beyond that. If you're rebuilding a bottom end and matching up crankcase hardware, check the length and thread against what's actually in your cases before ordering, since crankcase bolts often come in a few different lengths depending on position.
The manufacturer tag on this one says BSA, but nothing in the description or figure title tells us that for certain — worth confirming against your parts book if you're not sure whose crankcase you're working on.
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