Folding handlebars on a Brompton?
 

Did anybody try folding handlebars on a Brompton? I would think a person who have a S stem and want to ride more upright could use them as the P bars when riding but then fold them down to avoid them hitting the ground when folding the bike.

Also should be possible to create all sorts of riding positions. Good fpor long trips or if several different peopel use the same bike.

Pix of Bromptons with folding handlebars?

http://www.sjscycles.co.uk/humpert-a...amp-prod24407/

http://www.sjscycles.co.uk/images/pr...arge/24407.jpg

ahhhh hahahah! i was just about to order one of these.. been thinking about it for weeks.

mmmm ... got to look at that......

Order and report back!

What sort of bike would you use it on?

I have a Bike Friday, their option, a bar that splits in Half. as a Packing in a Suitcase expediency.

Those look like an angle adjustable sweep.

Modolo Dumbo was another option, there the height is another adjustment .
1" OD, U shaped upright so probably suited to a M or H bar alternative. U shaped wings of 7/8"tube.

write and ask 1st, those may require an open face stem, so you are SOL.

Was just thinking the same, open face stem or "aber hallo" type solution. Sounds like we are ending up with a heavy and expensive solution.

Brompton need to alter the top of the handlebar to open face.

Burn Paint at a Frame builder and take charge of the situation,
with modifications to make it what You Want.

a machined steel block, bore out to 1" , drill and tap 4 holes in the corners,
then split the block thru the bored inch hole to halve it, with an 1/8 inch removed.

re drill the 4 threaded holes on the top half, to take out the threads.

Bore a locating ring in the bottom to make a better brazed Joint than a flat Butt fillet.

and Braze it onto the cut off tube, after prior clamp with 1 bolt is removed.

Or at least that would seem a logical ordering of the steps involved.

then get the whole thing re powder coated.

have to replace the hinge pin..

another method might be to add what is to be 2 hinges front and back to the
existing Clamp. then after welding the sections of the hinge tube in an alternating
pattern cut thru the inside-out just enough
to have the 2 sides open up.
around that Hinge you created, still use the original 1 top Bolt.


a Beheading another open face steel stem , and making a graft on the B part is possible.
(alignment is crucial)

though a QR Post clamp and making the other portion, telescope, also can and has been done.
http://groups.yahoo.com/group/Brompt...36239/pic/list
British Modifier SP has even put a suspension post as an upper portion, /handle bar clamp.

Think I must read this again when I have more time to find out what you are actually saying. I think you are suggesting making what I want from scratch.

No framebuilder around here - or powdercoaters that I know of. That is why I tend to do my stuff myself. There is a welder approx 15 kms from here but he is mainly repairing farm equipment but he is helping when he can.

I think if I wanted to look into my own latest solution (that I think you are also commenting on) I would try to avoid extra work involved in producing a new "top" from scratch by digging out one of (too) many stored steel stems, ahead or beefy quill stems and see if I can cut of the part I want and have it joined t what I have (B stem)..

We`ll see. Not going to look close at the bromptons until January or February. Just doing some thinking for the time being.

This looks cool, before delving into adjustment details:

http://www.humpert.com/en_media/bike...RIOAHSSL_E.pdf

For the folding aspect of it, this provides no more function really than a flat bar with bar ends. You need to turn the hex bolts to do any "folding", so folding isn't really what this should be called. You could do most of the same folding with the bar ends and rotating the bar in the stem, or removing a faceplate, removing the bar, and turning that.


Thought from first look that maybe they had a cool button to press that lets you go from the chosen angle to getting the bars folded inward. You'd have 2-4 hex bolts to undo a stem face plate, and 4 bolts here on their handlebars.

I do not agree this (mounted as a P bar as i was thinking) could be replaced by a flatbar with barends, absolutely not. I do not use my B as a dayly commuter and have no problems dealing with a hex bolts or four. There is always a multitool in my pocket.

Nothing in the pdf scared me off but the weight does, approx 650 grams.

Maybe just look for a bar with a larger sweep angle?, minus adjustment?

Sweep in what direction? Bacwards? Got some great bars w sweep I bought from Thor but not sure what to do with them when folding. Maybe rotate so sweep is pointing down before folding, then the ends would point up after folding. Could work but is not exactely what I was looking for this time.

http://www.thorusa.com/accessories/handlebar.htm

Scroll down to "Satori Vienna"

ok, my head is willing to cooperate today so I understand at least this part of your suggestion.

Your first suggestion that I quoted here is almost the same as mine in my first comment to your post.

The black and white B I like, this is what I did to mine but I have not yet managed to find a good quality stem with the right profile. I`d like to buy a stem like the black one plse!! Mine is sticking out too much and poking into the spokes at the moment.

I can see from the photo his stem is insertet (lowered) quite a lot when folded, I may need to look further into that. Also want the stem to be alu for weight reasons. I have played with inserting a seatpost w a quill stem on top but I want a cleaner look and low weight, like the black/white one.


I have seen pictures of similar solutions with suspension posts. Not sure if I want the extra weight but I like the profile of those posts also.

I think you missed my point - the "foldability" of a flat or other bar with bar ends is similar to the Humpert. You'll need a hex key for doing either. So why pay the premium? And it's a moot point - this bar won't work with Brompton without some other parallel connected stem such as Aber Hallo.

Hex bolts like this aren't made for hundreds or thousands of insertions/extractions. You'll run into problems. Even Humpert themselves recommend replacing (see the PDF) this at either the smaller of 3 years or 10k. It's not really listed in their design intent either if this is made to be folded constantly. Sure, do it occassionally, just like pull off normal bars occasionally with the same hex key.

But could the HEX bolt be altered to a QR? LIke little pixel did with the Aber Hallo on his Bromptom.

Ok. "foldability" I agree it could be similar (depending on the bars and barends used). Riding position (height of hands when riding) no.

Not sure what sort of problems I would run into (sounds exiting by the way). If they break they do not break like a twig, and If I liked them I`d buy another, and another, and another..

Problems (challenges as I call them) is what we learn from and is what makes life exiting!

Been thinking about his short quick releases the last few days, wondering where he got them from (but just now I forgot what I want it for..):)

That is interesting. I recall reading about the Dutch builder who does this ...

http://www.eerdermetaal.nl/brompton_...satiebrug.html

Thanks for sharing fb.