Ran out of gas = improved performance ?

[flainn]

Yesterday while riding home I learned that the fuel cock on my GZ250 does not work the way I thought. I thought it was on "ON" while it was actually on "RES". This is because the selector is, IMO, poorly designed, and also because I had never run the fuel down that low before. I guess I should have paid more attention to the fuel selector in the manual...

My odometer read 244.x miles when I ran out of gas. Fortunately, I was near the top of a hill on so I simply turned around and coasted back to a gas station. I think quite a few people were laughing at the guy pushing his big cruiser back to town.

3.743 gallons to fill up from bone-dry. With premium fuel that cost me $8.38. I got 65.2 miles per gallon riding mostly from home to work, about half on the highway (55 mph) and half in town (25-35 mph). I don't always ride conservatively, either, so it still gets decent mileage even with quick takeoffs.

The interesting thing is, though, that I think running it out of gas was actually good for the bike. Ever since I got it running last August, acceleration has been not-smooth. When I would first open the throttle it would take off, then drop off, then take off again. Also, recently it started backfiring when I would let off the throttle completely while in gear (I posted about that a while back). That was annoying but didn't seem to affect performance.

Well, yesterday morning (before I ran it out of gas) it took some effort to start — a bunch of cranking and messing with the choke, and then when it started up (on no choke, as it turned out) it revved way up. So I tweaked the idle set to bring it back down. I noticed it seemed to be running smoother (and the exhaust sounded throatier) than usual. And, best of all, it did not backfire the entire way to work. Not only that, but I had completely smooth throttle response and noticeably more power than usual. Same story at lunch and going home after filling the tank.

Maybe a jet finally unclogged, or something? Not sure. Last August it took quite a bit of seafoam and cranking the engine to get it to finally fire up, but it has seemed to run well (with the exception of non-smooth throttle response) since then. I've been meaning to give it a tuneup once the weather got warmer, but now I'm kind of thinking I should leave it alone!

Now that it's got more power, I need to take it up to 65-70 and see what the new top end is. I haven't been able to get it to do much more than 75 on the flat so far, but that's probably as much due to the fact that I need to lose 40 pounds as the fact that it's got a small engine.

All in all, I'm pleased. It's now acting more like I expected this bike to act. I wish it hadn't taken eight months to get here, but hey.