Join Date: Sep 2011
Location: Dunstable, MA
Thanked 4 Times in 4 Posts
Sled: 2001 ZR 800
Yes, smaller jets = less gas consumption. It's like drinking a drink with a smaller straw. Takes longer. But keep in mind that the factory jets tend to be set to err on the side of being rich, to avoid a meltdown during the warranty period. The factory spec and even the manual suggestions are just a starting point. Then it's up to you to fine tune. You don't just want to go lean on a hunch or with the hope you'll get more zip. If you're already lean and you do that, you'll find yourself vacuuming your piston out of the lower casing in no time.
If you have EGT sensors, that helps. Should run between 900-1200 degrees farenheit. Colder and you're likely rich, hotter and you're likely lean. Plugs tell you a lot too. But the key is in the piston wash. A properly tuned motor will have burnt carbon on the head of the piston on all but the outer half inch circumference. If it is all black, the piston is getting too hot and you're running lean. If it is clean on more than the outer half inch of the piston, its running too cold and that means you're running too rich. There is a thread on here with photos of each condition (rich/proper/lean). Very helpful. Search "piston wash" or check my posts to find it. Use a bore light in the spark plug hole with the piston at BDC to view the piston crown, or pull the head off. I suggest that you buy a bore light or make one. I bought an incandescent LED at Radio Shack for 79 cents and soldered wires to it with heat shrink for insulation and ran the wires to a battery pack with 2 AA batteries. Sink the light into the spark plug hole and take a peek.