Dahon Classic III 1988 here. I'm already hesitating to post this because I'm not sure how to describe it with my imperfect English. When riding, pedaling feels strange. Not all the time but for example when slowing down there's this... subtle "slammy" feeling. I'm really struggling here explaining this. I'm hoping some of you Dahon owners know right away what I'm talking about.

If the bike has cottered cranks you have a cotter pin that needs to be tightened or replaced.

Make sure the hinge frame is not excessively worn. I have owned a number of these and all were garage queens and under used so they showed no signs of wear. Make sure the frame hinge closes snugly with the cam lock mechanism and the spring clip is in place and does not allow an unintentional opening. Moving up to where the brace attaches to the handlebar. Ideally there should be no play hear, but old or worn plastic insert is the usual find. If so you can apply "shoe goo" to the insert and after drying drill out to spring pen diameter. Alternatively just shove a rubber garden hose washer under there to wedge things snug. See pics from rehab from a couple of years ago.

Thoroughly inspect this hinge. cam lock, safety clip and restore to like new operation


Brace goes from top tube to handle bar stem. Inspect connection points.


Hand Tighten folding crank before riding. If it wont tighten place a fiber washer between crank and arm bolt

Yes, your description sounds like the feeling of a loose frame hinge clamp. They tend to come loose, but they can be tightened. Also make sure that any play in the steering hinge is taken up with a rubber gasket of some kind. The plastic cover for the steering bearing is often lost by the time the bike is sold.

Hi.. Any idea where to get the brace locking mechanism? (I'm not sure what it's called). Mine is missing one ball bearing. Thanks!

I don't think there are parts are available for the the 80's Dahons. A donor bike or a improvisation repair may be the only options. Is it possible to disassemble the mechanism and replace the missing ball?

The quick work around solution that comes to mind is removal of the spring loaded pin brace assembly and use a bolt with a wing nut in its place.

Thor Bikes has some older Dahon stuff, not a lot, but some.

In case original poster does not know who Thor is, link provided.

Hello,

and thank you all for your replies, especially zebede! My plan was to shoot a video or maybe even several videos to better understand what's happening and share the videos with you. But then winter arrived and well... I'll get back to this after snows melt.

Please, update us on this, if I can I will help.

Yes, ended up disassembling the lock, measured the ball bearing and ordered them online...

Thanks for the link!