I have a 94 xt350, been pretty great to me. But in the fall I had removed the air box cover (had put in a new uni filter) seemed to run a bit better. I was riding it pretty hard in the fall, and after stopping for a couple groceries near the end of my commute home, realized that after start up and arriving at the first set of lights a huge cloud of smoke from what I thought was some 'inconsiderate automobile' then saw it was my exhaust blasting out that smoke. Soooo, being fairly close to home, I puffed home a kilometer and parked her. I was thinking rings, and that now would be as good a time as any to teach myself to redoe the top end. A few days ago, I said what the heck and got it going, ran it around the block....no smoke! looked again last night....the big idiot i am, realized after the fact....no oil visible in the sight glass, added a liter, thinking 'oh, maybe no smoke due to no/low oil', started again, and around the block like a dime, with no smoke again.....whats the deal? (engine sounds great still!) side note, not sure if totally related, but i believe around the time I removed the air box cover (in the fall) when accelerating at highway speed, it seemed to cough and sputter here and there (looked in 'trouble shooting' in the xt manual and seems as though that problem would stem from carb issues.... thanks in advance for your thoughts conclusions and/or suggestions!