I've run another tank full since changing to the 18/42 combo. Noticed a big difference in gas mileage. I had been getting about 36 mpg avg. and now getting 42-45. I no longer look for 6th gear but have a new problem - I find myself FORGETTING to shift to 5th. I was on the highway today and twice realized I was over 70 and still in fourth. I've decided to order a 43T rear sprocket tomorrow. I'm convinced it would be the best combination of keeping the quick tighter low gears and still getting a higher 5th. If the mileage splits the difference as the gear ratio, I should still get 40+ mpg. I'll post an update after changing. If I can do it soon, I'd still have time to change back before Bike Week, if I need to.
