Folding Bikes - Swift dimension?

I am modifying a Dahon Speed to look and feel as stiff as a Swift (as much as i can) so i'd like to get some dimension.

What is the size of the headset?

What is the lenght of stem riser? Inside diameter?

Is a 22.2 * 25.4 stem riser inserted into the fork and then the 28.6 (OD) long stem riser inserted over ?

At the risk of being a spoil-sport: don't bother.

The Dahon design is flexy, and that's all there is to it. I believe the hinge in the middle of the frame is the single largest factor. The Speed also has a steel frame and thinner tubes.

Keep in mind that the Dahon frame geometry is similar to the typical Bike Friday -- but the BF's are much more rigid. Even a Brompton has a more solid ride than the lower-end Dahons. Swifts, BF's, Bromptons all have solid tubes.

Swapping out the handlepost will not significantly decrease the frame's flexiness. If it could, Gaerlan Cycles would offer its customers a rebuilt Dahon with a better handlepost setup. ;) In fact, you should give them a call, tell them you think the bike is too flexy, and see what they recommend. When I asked, they politely told me that there's really nothing you can do.


In terms of looks, the "top tube" (for lack of a better word) on the two frames are too radically different to make the Dahon look like the Swift. The Swift's tube is parallel to the ground at 24"; on a Dahon, the front of the tube is at around 23" and the rear at 17". The angle is just too dramatic to make the Dahon visually resemble a Swift.

To put it bluntly: if you want a Swift, go buy a Swift. :D

I was Swift owner in 2001. I really liked it.

Fast Forward 2006.

If money was plenty (i am probably in my worst money years since 15 years), i would buy a Bike Friday or a Swift BUT i am on a really tight budget. Since i have built 7-8 recumbent, have some tubing on hand, know how to braze, i will try to make the old Dahon Speed works a little bit better. In fact, my girlfriend ride it with a stem setup similar to Swift and is less flexy and LESS noisy. No, it won't even be equal to Swift but not too far. My hot rodded Twenty feel at least as stiff as a Swift maybe more. I may replace it with a similar modified Dahon (a close friend will give it to me if i want). This way we would own two identical bikes. I prefer travelling with similar bike.

I would like to get measurement to help me a bit.

Thanks.