I received my vacuum testing kit today, four gauges and rubber tubing, but also the stuff in the picture.
I am confused what these are all for and how to use them.
The ones on the left have too small a diameter/thread to fit the bike, the ones on the right do fit, but there are only two of each? So why then send four gauges if I can only do two at a time?? I also don't understand why there are rubber O rings and a nut for each copper pipe as when I put the nut on the pipe and try to insert the pipe into hole in the manifold, it wont fit?
And what about the grey plastic things?
Can anyone shed some light on these and how to use them?
The brass tubes are your adapters. The issue of trying to be universal, I suppose, means you never get as much as you need. I had to buy all my adapter ports seperate.
The nuts are locknuts for the adapters, and the o-rings are for air seal. Thread the nuts on all the way, put on the o-rings, thread the whole mess into your intakes, then run the nut down to lock them in place. A bit over-engineered for what they are.
The things in the middle are valves to tamp down on needle flutter. Without them, the pulsing of the engine whips the needles too fast to get a reading. You basically tighten them down enough to eliminate this flutter, but not so much as to cut off the vacuum entirely. It'll make sense once you're actually using them.
Myeah, I tried putting on the lock nuts all the way but then the brass tubes would not catch enough to lock onto the manifold. But thanks on the pointer for the valves to address needle flutter. I understand now.
Thank you Scotch for the link, that is exactly the set with the blue plate I bought (not because of the nice set in red btw!). It was cheap (£27) and I was only going to buy one once as well, plus I wil share with my friend who has a large collection of bikes, so once I have mastered the art, it'll get used.
I actually have a small rubber hose looping from the vacuum port on cylinder 3 to the one on cylinder 4 (anyone has that too and know why? Maybe a link to the petcock?) ...which means I actually have four possible 'outlets' to connect up to, but I don't understand why the set did not come with four of each rather than two of each...? Anyway, going to have a go tomorrow.