Print Page - A65 Rear Chain Oiler from Primary Case

Title: A65 Rear Chain Oiler from Primary Case
Post by: Whalen on 13 Aug, 2025, 14:03

Hi, my 1971 A65 Thunderbolt has lost the rear chain oiler that is bolted into the back of the primary side case. Making a real mess with oil coming out onto surrounding area.
I'm thinking to plug the hole with a bolt - parts list says 1/4" UNC.
Is there a 1/4 UNC elsewhere on the engine I can try to see if it fits?
Tried a bolt from the same position on my B40 but it seems too small diameter.

If I take the primary chaincase cover off, can I see the oiler hole from the inside?

Title: Re: A65 Rear Chain Oiler from Primary Case
Post by: Gup holland on 13 Aug, 2025, 19:36

Yes here a picture from the inside, small hole

Title: Re: A65 Rear Chain Oiler from Primary Case
Post by: Gup holland on 14 Aug, 2025, 16:29

When clutch is fitted

Title: Re: A65 Rear Chain Oiler from Primary Case
Post by: Tigerfeet on 18 Aug, 2025, 13:05

I find the chain oiler on my A50 to be invaluable. I have never oiled the chain in 20,000 miles. It will occasionally leave a drip on the floor when parked - but that reassures me that the oiler is still working. I'd source a replacement - rather than blocking it off...

BSA Owners' Club Workshop Discussions

The BSA Workshop => Twins => Topic started by: Whalen on 13 Aug, 2025, 14:03