I don't mean to jump in and hijack, I just thought I'd share a couple links that might be helpful, and talk motorcycles a little bit.
The best info I've come across on the web for understanding and tuning constant velocity carbs is at Factory Pro's website:
CV Carb Tuning Procedures
Having an O2 sensor should make the process considerably easier. I bought one of their pre-set kits for my Honda Blackbird, but ended up selling the bike before I put the kit in it.
FWIW, I got about 70mpg US out of my old KZ400, and 53 from the KLR650. A non-oring chain has noticeably less drag than a sealed chain. Non-oring chains need good lube though (or at least lots of it-my brother fills his scott-oiler with used motor oil and slathers it on liberally).
This site (
Watt_man on Xanga ) has some interesting info, including test results on an o-ring chain run for 34,000 miles using only WD40. He also makes a thermostat modification for the KLR that allows much better control of engine temperature. The same principle should apply to other water-cooled bikes. My air/oil cooled bmw has a thermostatically regulated oil cooler, and it maintains the same oil temp from -5c to +40c (20-104 f) as long as you keep moving, but the thermostat itself is ridiculously expensive (~$200, IIRC), so it might not be a worthwhile mod. Other makes might have the same kind of thing for a more reasonable price, though. (BMW stands for Bring More
Wampum and I don't mean the seashells.)
The type of road surface seems to make a big difference to tire life. Where I usually ride, they use sharp crushed gravel in a seal-coat on top of asphalt. Very good traction, but short tire life (~6,000 miles from BT020s on an R1100RT). I've heard of people getting 50% more miles out of the same tires on the same bike in parts of the country where they use concrete for the driving surface. Some people in the SW US report getting even fewer miles than I do out of a set, probably due to high temperatures on a similarly abrasive surface.