Troubleshooting a JAP Special

[Rockburner]

Interesting conversation with the Guru this afternoon....

I hadn't realised it, but that banjo "post"  fitting has a counterpart in the Pilgrim pump outlet, which is BSP as standard, and the Rocker box fitting is BSC as standard.

Here's photos of the 2 parts from the supplier...





Apart from the machined channel on the upper part.... they're both nigh on identical banjo fittings.  It's quite within the bounds of probablity that the BSP pump outlet part (the lower photo) has been modernised to have the channel cut into it to improve oil flow and that photo is of an older style part, so the parts would look virtually identical when you're just picking them up and throwing them into a package.

So it's quite likely I've just been sent the wrong part...  hey ho, I can easily see a mistake like that happening, we'll see what they say at the suppliers....

[cardan]

Weirdly I was working at my bench this afternoon when I noticed a banjo fitting on the (very messy!) windowsill. I measured it: 1/8 BSP on the screw-in end and 3/8 BSCy on the nut end.

I have an Australian-made bike with a Spacke De Luxe engine, made in the USA. One of the fittings the oil pump is 1/8" NPS, which is major diameter 0.405", 27 tpi.

So 0.375", 0.383", 0.405"... 26, 28, 27 tpi... you've got to love a good thread.

Leon