[boundstaffpress]

Seems like a simple thing, but have you checked your tire pressure. Low tires, especially wide tires will dramatically effect MPG. Narrow tires, for whatever reason, yeild better milage. Same principal, something about contact patch and coeficient of friction.

A taller tire will act to reduce your rear end gearing, but will make it harder for you to get started. If you drive on the freeway a taller tire will help, but if you drive stop sign to stop sign, It only serves to eat more gas.

Rob Z. has some good advice. Build-ups never SAVE money. My wife can give you a long story about that.

If you do decide to change your setup, a smaller head, 180cc or smaller, will increase your low end torque and thus help get you started better. Has to do with velocity of air flow. Lower compression makes power lower in the RPM band, and will also improve in town economy, though minimally. And that brings you back to spending lots to save a little.