David,
I never went to quite the extent you did with your RD400, but I did perform a few mods. J & R expansion chambers, K & N air filter, TC Red synthetic injection oil, aftermarket reed valves, platinum tipped spark plugs, and dunlop K81 tires. Looking back, you had to be pretty much out of your mind to have a bike like that as a daily driver. I am sure you can relate to the incredible satisfaction of having some "dude" in a "hot" camaro, firebird, mustang, etc pull up next to you at a stoplight /w3tcompact/icons/wink.gif I can remember them creeping forward to get a good "holeshot" on the dork with the little Jap bike next to them /w3tcompact/icons/laugh.gif/w3tcompact/icons/laugh.gif/w3tcompact/icons/laugh.gif. As you know, the "race" was over almost before it began, with the "hot" car usually roaring past way after I decided to shut it down two or three seconds after the light changed. I'm sitting here chuckling about it now. Man, those were the days. Luckily, I survived that period and now just play with cool dudes in their tricked out "rice rockets" with the sound system that costs more than the car /w3tcompact/icons/wink.gif The old Nighthawk ain't no slouch either. Course, it sure isn't an RD.