It used to be the case that I could ride for about 230 miles before I started thinking about buying new gas, but ever since I returned from Hawai`i, it's been only just about half as much and I am wondering what caused the change.
At first, I thought it might be tire pressure (although even on bare rims I should be able to do more than that). I went to the gas station down the hill, who had air but no pressure gauge, and added a little. It made a huge difference: the bike got all bouncy, like a racing cycle fresh from the shop!
I have a gauge at home, so when I rode back I tested the pressure. Turns out the front tire was at about 45 psi (the manual says 36). No wonder it was bouncy! I let air out, checked the rear tire (which I hadn't inflated) and it was at its rated 42 psi.
Who's the culprit now? Will an oil change make a big difference? Will let you know, it's quite annoying to have to buy more gas every other day!