Parts for Triumph, BSA & Norton·Worldwide shipping·Call the Shop: (657) 231-9003
Le Hangar 23
Shop/Category/Fig. 1 — CYLINDER AND CRANKSHAFT/BSA Circlip, gudgeon pin
BSA Circlip, gudgeon pin
View clickable diagram
Details
Also known as40-979
DiagramFig. 1 — CYLINDER AND CRANKSHAFT · ref 35
Subsystemengine bottom
Listed in parts books1969

BSA Circlip, gudgeon pin

A small circlip that retains the gudgeon (piston) pin in the piston boss.

PN · 40-0979

This is the circlip that keeps the gudgeon pin (piston pin) captive in the piston boss. It's a small, simple part but an important one - without it in place the pin can walk sideways and score the cylinder wall or worse. The catalog lists it under the CYLINDER AND CRANKSHAFT figure, so it belongs down in the bottom end where piston meets rod.

Read more

The catalog record we have on this one is brief, just the single listing tying it to that figure, so we can't speak to which specific model or year range beyond what's on file. If you're rebuilding a piston assembly and need to match this circlip up correctly, give us a call with your engine details and we'll confirm fitment before you order.

It also shows up under the alias 40-979, same part, just a shorter number format some parts books use.

Not listed anywhere

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.

Sign in to request it
We need somewhere to send the price and the photographs.
Pin your bike to check this part fits.

Sorry if we got something wrong here. If you think this information isn't correct, .

Related parts
Gudgeon pin
PN 40-0978 · Goes with this
BackorderView
Piston complete
PN 40-0970 · Goes with this
BackorderView
Any questions about this part?

Ed is at the counter. Tell him what you're working on or what doesn't fit, and he'll take it from there with this part already on the bench.