| Also known as | 40-918 |
| Diagram | Fig. 1 — CYLINDER AND CRANKSHAFT · ref 49 |
| Subsystem | engine bottom |
| Listed in parts books | 1969 |
BSA Big-end shell (—.020")
A .020-undersize big-end shell bearing, catalog PN 40-0918, for a reground crankshaft journal.
This is a big-end shell listed at .020 undersize, meaning it's ground for a crankshaft journal that's already been machined down .020 inch from standard. It shows up in the parts book under the CYLINDER AND CRANKSHAFT figure, which puts it down in the bottom end where the connecting rod meets the crank.
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The manufacturer tag on this one says BSA, but we don't have a model or year spelled out in the catalog record beyond a single 1969 appearance. If you're chasing a big-end shell for a specific machine, best to confirm the journal size and fitment with us before you order — undersize shells are matched to a reground crank, and swapping in the wrong size will cause you grief.
The legacy form of this number is 40-918, same part, just written without the extra zero some parts books use.
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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