Originally Posted by
rahill
I've done 41 mph (66 kph) on my stock Brompton (S type) and found it quite stable. That was down the Laguna Seca corkscrew during the Brompton World Championships, which was loads of fun, but have hit similar speeds on regular roads too. There are enough potential wiggly bits in any folding bike though that one may handle differently than another.
That's a wild speed! I've been on the Corkscrew; I'd be surprised if you can hit that speed there. How did you measure? If GPS, if the data interval is too long, it could straighten out the Corkscrew out and report a higher than expected speed
But if that's a legit speed on a 15" Brommie, wow!