Gearbox grease nipple

[RichardAB]

On my B33 gearbox there is a small grease nipple to lubricate the clutch arm. Can someone advise please if this type of grease gun will fit the nipple or quote me a nipple size? Thank you (PS I know there are cheaper guns on e bay, link is example only)

https://www.ebay.co.uk/itm/Small-brass-Tecalemit-grease-gun-BSA-vintage-motorcycle-Tool-Roll-item/264443455243?_trkparms=aid%3D1110001%26algo%3DSPLICE.SIM%26ao%3D1%26asc%3D40732%26meid%3D6a45a7be9da94f9593886437d66205bd%26pid%3D100005%26rk%3D1%26rkt%3D12%26sd%3D173973391952%26itm%3D264443455243%26pmt%3D0%26noa%3D1%26pg%3D2047675&_trksid=p2047675.c100005.m1851

[AdrianS]

That grease gun may well be ok but it relies on pressure against the grease nipple face when pushing the grease gun for a seal.
I don't think the modern type of grease gun with the " click" fit onto the nipple will work well.
I would also remove the nipple and soak it in petrol to clean out any old grease as they can become blocked easily. I found an adaptor for my modern grease gun which is basically a cone that has a very small outlet at the end. This can be pushed into the nipple dislodging the sealing ball and then squirting grease in or even taking out the nipple and using it directly into the hole and just using the nipple as a plug.
I believe my cone adaptor came from ebay.

[RichardAB]

Thank you