Leaded fuel and Race Gas - especially if it's ELF leaded racegas. Reminds me so much of racing and my childhood back circa 1969 (when pumps dispensed leaded gas... up to 1972. Don't tell me Regular gasoline was leaded after 1972... it wasn't). Getting gas in my dad's metal can for the lawnmower. Or, in the case of racegas, getting ready in the morning for the first practice session, feeling the adrenaline picking up, but playing it cool, then getting the whiff of racegas in the Rider's Meeting...
I guess I need to say 'two-stroke exhaust' too - castor or other. Castor reminds me of model airplanes (can you say 'Cox .049'?) and bike/chainsaw oil makes me think of that first motorcycle, a 1969 Suzuki 50cc something or other... oh the times we had together :)
I too like the first minutes of rain, but don't associate it with anything. Creosote bushes have a smell in light showers, but nothing specific comes to mind (other than me telling myself I need to get the hell out of the city and into the desert more often. I've since moved away :( ).
Warm pine forest smells I associate with July, 1983 and a camping trip. Most of the Sonoran Desert (sagebrush), and much of the high Rockies pine elicits that in me.
Lemon and some limes. I had both in my house in Arizona. And rosemary, too. All three remind me of my awesome house in Arizona and that I had to leave it because of work.
Hops - the live vines and even pellets/cones while brewing. Reminds me of brewing, oddly enough (I gave it up around 1999).
There is a certain combination of vanilla, wax, and coconut which I strongly associate with a former fling. Late January, Stratton Mountain, Vermont, in the early 1980's and that is all I will say.
Mimeographs. Kids today just will NOT understand that scene in Ferris Bueller.
Baking pecan pie, or baklava in the oven just brings back my Grandmother getting ready for holidays.
Ozone. Reminds me of a model train I had, and the fantasies of growing up to be a train driver (my bedroom, early '70s, when I was maybe 5 or 6)
Smoked Whitefish. Instantly makes me salivate/stomach rumble. Reminds me of Park Avenue in NYC, mid-late 1970s, the era when Bonham and Moon died from excess (I remember conversations at family gatherings/events on that and the Falklands war, while eating whitefish on toast points...). Haagen-Daz vanilla will bring me to the same point in time, but not the same 'gotta have it' craving (I very seldom eat ice cream).
Fresh (like you pull the bulbs out of the ground by the greens) Garlic. Just so much can come to mind when smelling it.
Pretzels - Bavarian style - remind me of a trip to Bush Gardens, but I can only remember that it was NOT Tampa, it was another city. Want to say 'Williamsburg'... don't think that facility is still open. But I remember not liking the rides, so I was in my early teens; we were in some sort of 'Bavarian Gasthouse' with a lot of beer which my Mom and Aunt let me have :). Fond memories indeed. Anyway, I avoid Auntie Annies in the mall (hell, I avoid shopping, let alone at a mall) because it isn't the same. But at a baseball game... I'm without willpower. Camden Yards was really bad for that, and I suppose my next pretzel will now remind me of Orioles' games.