seanof30306 wrote:Don't have exact numbers yet. The gauges are off being refurbished, so I can't track it precisely.
Before, it was getting 36 mpg. I was getting about 120-125 miles out of a tank before I'd have to switch over to reserve and start looking for a gas station.
Last week, I rode it back and forth to work 4 times (32 miles each day), and rode it at least 30 miles on my day off, too. I know I got 124 miles from the to-and-from work riding, and at least another 30 miles, which would translate to a 5mpg+ improvement. Won't know for sure until I get my gauges back.
Even if I am getting 40+mpg, that's still not where I think it should be. Lots of guys on here are reporting 50+mpg.
I've upgraded to electronic ignition, the carbs have been rebuilt to (near) perfection, and I hypermile it. If all I end up getting is 40-43mpg, I still have some work to do.
For highway mileage, I found that air drag was a major factor because you have to open the throttle more to push the air.
When I changed the gearing on my 750 twin, the mileage didn't change much. It seems like I have always gotten about 40 mpg city and the highway mileage is VERY speed dependent.
At 60 mph I would get around 60 mpg, and when I cruised at 70 - 75 it dropped to about 45 mpg.
My brother had a KZ-650, I recall it didn't have as much torque as my 750 twin. Lowering gears can possibly get to an operating point where you have to increase throttle opening to get enough power to pull the gear, and mileage may not increase (it can actually drop). There's an optimum point for the load, not sure what it is. On mine it seems like dropping the gaer 16% didn't really buy gas mileage, but it cruises much smoother. I hated hearing the engine scream at 75 mph (revs were about 5300).
