| Diagram | Fig. 7 — CLUTCH · ref 31 |
| Subsystem | engine bottom |
| Listed in parts books | 1969–1972 |
BSA Key — crankshaft pinion
A crankshaft pinion key that locates the timing pinion on the crankshaft end.
Part number 40-3150 is a crankshaft pinion key, the small piece that locates the timing pinion on the end of the crankshaft so it can't spin independently of the shaft. It shows up across our records in the clutch, primary cover, and crankshaft figures, which tells you it lives right at the drive-side end of the crank, in the area where the primary drive and timing gear take their power off the engine.
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It's a plain, functional piece of hardware — no moving parts, nothing to wear out under normal conditions — but if it shears or works loose you'll get timing gear slop or a pinion that won't stay put, which is not something you want to chase down after the engine's back together.
Our catalog appearances for this one run from 1969 to 1972. We don't have a specific model tied to it in our records, so give us a call or check it against your own crankshaft 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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