Duragrouch

I'll also add to the choir, I have a folder that is my townie, long exercise ride, and can tour long distances. Didn't start out that way. I had an early Dahon 3 speed with a rack and recyling crate on the back, someone cut the U-lock and stole, I think mostly for the rack, which was a nice one, adjustable height but sturdy. Replaced that with a Dahon Speed 7. Worked great. Found a rear rack that fit far enough aft for heel clearance with panniers, great. But it was always geared a bit too tall for the steep hills here, 52x11-30, and just a smaller single chainring would be too short a top gear. Finally, after 7 years, I got around to fitting a double crank, which I was told couldn't be done, but worked. First tried to fit a triple, 52/42/30, would not work because the low ring was too far inboard (due to the oversize seat tube), needed a wider-than standard BB spindle. Then found a better quality double, 50/34, almost as wide a range, it worked, via a derailleur mounting adaptor, and modification of the front derailleur. Bike was transformed, 21-85 gear inches. Cargo capacity is greater than a large-wheel bike. Center of gravity is low. Loading improves stability of small-wheel bikes. Frame fit for me is perfect (5'8", fixed (tall) Dahon stem, clip-on aero bars for stretched out). The bike is perfect, except for wanting disc brakes for the steeps; For that I would start with a Dahon Launch, which should be nearly identical in geometry (but aluminum instead of 4130 chrome moly steel like the Speed). It bugs me that Dahon discontinued the Formula 18, had disc brakes and double crank, but the latter was 130 BCD and I think 53/39.

I haven't touched my racing bike in many years, nor the hybrid bike I used as a townie after the first Dahon got stolen. I'm not a "frequent folder", but my wagon car got totaled from someone running into it parked, and I just wanted a folder to more easily transport on occasion, and be smaller in my tiny living space. It's vastly exceeded my expectations. For this point in my life, it's the only bike I use. For exercise when traveling, no touring loads, I'd love a Brompton, and would grab one if I see cheap. Don't laugh, Bike Fridays have sold so well, they are common on craigslist at less than half new price (though most have IGHs, which is unnecessary on a 20" so I won't touch). I've seen Brompton copies from China, but wouldn't touch one unless less than half actual Brompton price, and during the pandemic with shipping prices way up, was going to be like 2/3-3/4 Brompton list, no way.

But to sum up, the riding position, balance, speed range difference between an early 16" wheel Dahon and a 20" folder of any brand, is like night and day. Even a Brompton 16" will be better, because the tri-fold frame allows it to be longer in wheelbase and position, both of which cure a lot of ills versus the early Dahon 16".