A while back when I first posted about my Giant Halfway, bike forums member "Northshore Man" suggested that a nice way to get more speed was to switch out the 13-28 freewheel for an 11-28. Unfortunately, the 11-28 freewheel (only produced by Shimano) has been discontinued.
I've scoured the internet, but the closest I've seen is Harris Cycles who has a note that they might have some again in August of 2008. I sent them an e-mail but haven't heard back yet about them.
Does anyone here have any info on where I might find a Shimano 11-28 freewheel from an offline source? If so, please PM me or post here. I want to give this mod a try.
If this doesn't work, I'll delve a bit more into figuring out if a hub replacement is possible. I'm not sure how much of an option that is with the Halfway design though.