Just bought a B40..looking to ride .I cannot see a level plug or drain plug of any description.It has the auto chain oiler which is dripping great pools of oil on my tarmac.Can anybody help please .
invest in the oracle, sounds like you may need it.
http://www.ratiopublishing.co.uk/
+ users manual & stuff here:
https://www.bsaunitsingles.com/Archive_home.htm
Hi before posting my query I had scoured the BSAOC manuals available but they are limited in detail.My Haynes manual shows a pic of the chaincase with both drain & level plugs ..mine aint got them .That is why I went to the forum.This bike was first registered to the army Jan 1965. engine No B40F687.I wonder if there was a different spec,logic tells me that as it has the drive chain oiler it must be possible to check the oil level in the primary chaincase ?I will buy the suggested oracle which may answer the puzzle ,in the meantime hoping for a few more replies .
sorry reply was a bit short, but having trouble with forum and my laptop.
Rupert is THE knowledge for B40's, and has done much testing and work on them.
normally the level plug was a screw around the chaincase and the clutch adjusting plug was the filler until the oil came out of the chancase screw hole.
the problem with Haynes, is they work on one year bike and adapt if a major alteration, Im currently working on a 125 varadero only manuals are for early ones not the fuel injected later ones. something stopping me removing the tank.. in your case, if they worked on the twin oil plugs they have not worked and photographed the screw version.
when HAynes first came out, we all complained about the bike ones, the car ones were ok but the principles were transferred to bikes which work on a different principle. they are better now, methodically the genuine workshop manuals tend to have you jumping from one chapter to anther and back again.
there are service sheets available for the B40 and other singles https://www.bsa-oc.com/en/service-sheets-2/ sheet 422 fig C5a bolt M is level one.
I have a 1965 B40F. My primary chaincase drain plug is one of the allen screws. The level plug is one of the other allen screws. The manuals etc should show you which. Phil.
That is brilliant,you have solved the issue,many thanks.I will still buy the oracle for future use .Just to bore you I am nearly 77,have had many bikes fromm bantam to present Bonnie 1200.I have always wanted an old thumper to ride & tinker with but could not get my head round this little problem.Think I will block off the auto lube !!Thanks again for the guidance .
The auto lube for the chain can be a pain in the arse. If you are not doing many miles then block it off either by replacing the outlet with a bolt or crimping up the copper tube. you can partially close the copper tube to restrict oil flow a little if you still want the chain oiling. Mine used to cause quite a few oil drops when stationary which annoyed me as the engine was otherwise oil tight!
apols for being brief too. It's on pg 36 in the 1965 manual via the link....but yes is seemed a bit strange to me too that the case screws are used as the level and drain plugs.
Rupert ratio Vols 1 & 2 l a must really and we're very lucky to have this resource. Mind you, I think the user manual is still a god read...particularly if you can find an original with a few oily finger prints on it.