stmalk

I tried to tighten handle post on my Dahon Mariner D8 tonight and I think something went wrong and that little square white plastic thing that is placed between the hinge bolt and a lever popped out. I tried to put it back on a bolt, by pushing hinge back but it doesn't go back enough to fit that part back in. I'm not sure how it even popped out.
Does anyone know what to do with it? I guess I need to undo screws of the hinge and put that white thing back on that way. But there are springs inside the hinge and I'm not sure if it's even safe to undo these screws and if I can put it all back myself after it.
Here are the photos:

stmalk

Alright, I took this metal hinge out by undoing the screws. Springs popped out as I expected, but I managed to turn it a bit and slide this plastic piece back in. Then I tucked springs back next to the bolts. So apparently when I tightened both bolts too much they pressed against this plastic part too much and prevented a hinge from moving when folding. This applied too much pressure on a plastic part and it popped off. Loosening the bolts properly and balancing them out so they are both tight but loose enought to allow hinge movement resulted in a plastic piece staying in place and folding mechanism working as it should. I'm happy I didn't break anything, hopefully nothing cracks when I commute 20 miles tomorrow haha.

pastorbobnlnh 

Thanks for sharing your experience. I'm certain it will help other Dahon and other folding bike owners in the future. Hopefully your commute is uneventful!

wesgreen

Good job!

Artmo 

I see your post was a while ago, but I took the sliding locking piece apart and one of the springs popped out, but I can’t get back in at the same time as I push the bolt in. Any tips would be appreciated. Thanks

Ron Damon

CFYI & FWIW, contemporary handle posts look like this. Seeing your image I was at a loss for what you were describing. The tightening is done via an external hex bolt so there's no need to fold or open the handlepost.

CrimsonEclipse

Try to close the post (place it toward the locked position) but not all of the way. That might make some space to put the plastic block into position.

Also, the metal plate is spring loaded so you can push it away from the hinge and make even more space

Artmo 

Thanks for your reply
My problem is not getting the block in, but one of the springs keeps popping out.

CrimsonEclipse

Ah. ok
Are the hex screws holding in the springs missing?
The locking plate is held in by 2 screws and there are two more small set screws that hold the springs in and are only accessible if you remove the locking plate (the big silver sliding plate)
The set screws are on the same side as the white plastic block

Artmo 

No. I'm a bit of a twit: We have two Dahons which I am about to give away to friends as we no longer need them. The bikes have not been used for years and when I lifted the bars to lock in place one of them, the sliding wedge/locking plate didn't move, so I decided to take it apart and grease the sliding surfaces, not realizing the presence of the small springs, one of which popped out. I have tried removing the small set screws and inserting the spring, but when I put the locking plate screw in, the spring becomes misaligned or pops out. I guess it's all up to my dexterity, which is obviously lacking, to get it together. At the moment, the air in my garage is blue!! But I'll keep trying. Thanks for your advice.
The other Dahon had the same problem initially, but after the above experience, I gave the locking plate a squirt of WD40 and it fixed it.

CrimsonEclipse

ok I remember now.
Leave the set screws in.
If you have a pick (metal or wood) you should be able to align the springs when installing the screws on the plate.
It's not an ideal design.

Dahons always being joy into your life.
The day you get one and the day you get rid of it.

Artmo 

Definitely not an ideal design. I already tried what you suggest, but failed. Have just given both to our friends with instructions!!
Thanks for your time.

sweeks

See THIS video showing the dismantling of the latch mechanism. The sliding plate seems to be installed with the springs in place; these are displaced to install the retaining screws. The hex screws ("grub" screws) do not need to be removed. Notice at about 3:20 that the retaining screws are loosened slightly. This is because if they are tight the handlepost may be able to be locked in place, but the springs will not be able to retract the plate and the only way to unlock the latch is to remove the hinge pin... not something you want to do.
I have a Dahon Mu XL that I've had since 2006. The handlepost is like the OP's and I've replaced the white plastic block several times over the course of over 12,000 miles.
FWIW, I have enjoyed this bike the entire time I've owned it. I've been using it as my "winter" bike since I got a Tern Verge S11i in 2013, and the salt here in Chicago has finally destroyed the frame. It does not give me any joy to retire the bike; I used it hard and it did its job well.

The Mu XL "Winter" about 5 years ago. It was already pretty well thrashed by then. Notice the cracked seat tube.