I have a carb'd motorcycle which burbles & pops on a closed-throttle decel from a high RPM; I know why it & other carb'd engines often do that, but I have yet to figure out why this happens on fuel-injected engines as well. I'll be interested to see any answers which other members have.
As for your question regarding compressors & changing valve seals, what you need is a length of hose with a threaded fitting that matches that of your spark plugs. Thread this hose in to the spark plug hole, and pressurize the cylinder to keep the valves from dropping in after you remove the retainers.
Another method of keeping your valves up, is to thread a bunch of rope in through the spark plug hole, then gently rotate the crank by hand until the piston compresses the rope against the faces of the valves, holding them in place. Once you've re-assembled the valve seals & springs, rotate the engine backward just enough so that you can extract the rope.
With either method, it's not a bad idea to ensure that the cylinder is on its compression stroke. It'll make life easier if you're using compressed air to hold the valves, and you're less likely to jam a piece of the rope between a valve & its seat with the othe rmethod.
his: 1985 2M6 SE
poly'd, Koni'd, formula nose & factory sub
hers: 1984 2M4
all stock... so far
[This message has been edited by dguy (edited 01-13-2004).]