Since I've benefited from tips posted on Yahoo's Brompton message board, I hope some observations about my recent Brompton commuting experience are in turn useful to those of you wondering about the feasibility of somewhat longer commutes on your Brompton.
Ok, the Brompton folding bike provides a unique solution, but what kind of Brompton is needed and specifically what kind of modifications are necessary for longer-than-average commutes?
Similarly my choice of the superlight titanium frame option and a titanium seat post is driven by a desire to reduce the bike's weight both for riding efficiency and for ease of carrying. Yes, titanium saves weight but may be less than you think. If the added expense is not an issue and/or you can convince yourself you need a little retail therapy, well then by all means get the titanium package. But otherwise I think you're not really worse off with a standard all-steel frame and certainly a lot wealthier for it. That said, no matter which option you choose, you need a certain base level of upper body strength to comfortably carry a Brompton through a train station and on and off trains. In short, my current configuration works for me, but I can easily see being interested in upgrading should Brompton come out with a bike built with new materials that result in the bike only weighing - say fourteen pounds [hint hint].
Now my choice of a six gear model with the optional 8% higher gearing was the feature of the bike that I was most concerned about. My instinct was to lean toward the simpler and lighter option - that is, the two gear model. But I also know the frustration of riding with gearing that is too widely spaced such that the ideal gear at any given time feels like it should be somewhere between two existing gears. In this case, I am very happy with my choice of the six gears as it has allowed me to consistently find a comfortable gear. Yes, even with the optional 8% higher gearing, I still topped out periodically. And yes, I do have to get out of the seat and grind it out when I have to climb particularly steep hills. In the case of the former, it's not a big deal, I ease off. In the case of the latter, it's also not a big deal, as I often get out of my seat and grind it out even in my other bikes. In short, my choice of the number of gears and the gearing range has suited me well, but you might need different number of gears and gearing range depending on both the terrain you ride and your fitness level. That said, considering Brompton's relatively high price point, I think their shifters have notable room for improvement in a world where DuraAce and/or XTR shifters now set high standards for crisp and flawless shifting.
As for tires, I opted for the Schwalbe Stelvio narrow section tires, again driven by desire for the lightest and fastest tires I could find. So far, they've worked out well. I admit that on my other commuting bikes, I've gone overboard with Kevlar tires, tire liners, and puncture-resistant tubes. In other words, for these other bikes I tolerate heavier tires in exchange for presumably lower risk of getting a flat.
Last but not least, I don't use any Brompton lights. If I begin my ride at dawn, I just rely on front and rear flashers that seem to work well enough to alert car drivers and pedestrians of my presence. But if I begin my ride in the dark, I supplement these flashers with a helmet-mounted Nite Rider Flight light and rear flasher which I've used successfully year-round on early morning rides.
While I don?t want to oversell the Brompton folding bike as the ultimate long-distance commuting machine, I do want to convey how surprisingly well it can work for this purpose (not to mention how much fun they are to ride) albeit at some cost in terms of speed relative to full size road bikes.
In any case, I hope these observations are useful data points for those of you assessing the feasibility of somewhat longer commutes on your Brompton folding bike.