Friday, November 27, 2009

Merry Christmas Clive: Front Brake Hangers and Stops

My lucky bike Clive has already received his first Christmas gift.

Since my stem came hanger-free, I have been thinking over what the ideal location is for a front brake cable stop. Originally my idea was that the stop should be put smack dab in the middle of the stem extension. This is a crude implementation of the idea. I was thinking one could put a water bottle boss on the top of the extension, tap it out to M6, and then put an adjuster in the top. Two complications with this plan: you'd have to angle the boss such that it follows the angle of the headtube, which is the angle the brake cable needs to be at. And you need to drill an exit hole in the bottom of the extensions in the right place to follow that same angle. And then other questions: would it weaken the stem having a braze-on there? Stems are under a lot of stress, and you don't want them to fail. And would it be annoying that raising and lowering the stem would tighten and loosen the front brake? Also: this idea is pretty awful if you're using aero brake levers (I'm using these).

The other option for a stem-located front brake cable hanger is the one on this Singer stem. Very attractive, and simpler than the above-mentioned idea, since it doesn't pass through the extension. Also, it doesn't cut through the extension, so no chance of weakening it. The drawback of stem-adjusting affecting front brake position remains. And any stop located below the stem is going to cause the housing to rub against the stem, producing rattling and wear of the chroming.


Finally I decided that a headset-mounted stop—the most obvious idea—was probably the best one. Regular steel Mafac hangers are nice looking but don't have cable adjusters. Weinnmann hangers have adjusters but are funny looking. The nicest headset hangers are again those on Alex Singers. Since these need to be made by hand anyway, it would be easy enough to made the stop a threaded boss capable of handling an adjuster.

I sent the above link to my friend Olivier and he got an idea to made a headset-mounted hanger using wires rather than a tube. Before I knew what was going on, he had designed and built the hanger!—the one photographed above. And it's glorious! It's very attractive, it incorporates an adjuster, and it even has an extra "loop" to guide the housing into the stop and possibly reduce rattling and finish-wear. Ingenious! The only possible downside is flexiness—maybe prolonged braking force will serve to "flatten out" the bend of the wires. We'll see! Update: Some actual testing has revealed that it's way too flexy! Back to the drawing board!

Some of you may remember that I was originally going to locate the adjusters right in the brake levers, Mafac-style. I had my Mavic levers tapped for some very attractive Dia Compe adjusters. But since the brake lever body on these Mavic levers is split, the threading was a bit "loose." I'm happier having the adjuster anchored somewhere more stable—and those nice adjusters will look nice on Olivier's hanger!

9 comments:

RMHampel said...

I think the idea of the wire hanger looks nice, but you're right to be concerned about longevity. How about making the vertical section of wire and the attachment to the headset spacer (out to where the bend to the vertical takes place) from sheet steel? They'd be chromed, of course.

I'm having a similar, though simpler, debate with myself about the front hanger for the Rivendell Quickbeam I'm building up. The Mafac hangers look slim and long compared with the current thick and clunky aluminum models. The trouble is, I'm not sure where to get the Mafac hanger; any suggestions?

Your bike looks like it's going to be super!

Ron

AH said...

Hi Ron,

Yes, that's a good idea about the sheet steel. It would definitely eliminate the bend/flex problem: then the wire would only be stressed, not bent. My question: would it look nice??

As for finding Mafac hangers, a great place to look is in the parts box at a bike shop. There are lots of these kicking around! There are usually plenty on eBay, and Café de Vélo usually has them, but are now out of stock... Be sure to get the English ones with the notch rather than the notchless French, otherwise it'll twist around when you tighten the locknut on your headset. And that little ferrule that comes with the Café de Vélo one is important also!

Aluminum is a very good material for hangers, by the way. Not flexy! But yes, usually a bit ugly. I do like these ones.

RMHampel said...

"... would it look nice??"

That is the question.
Thanks for the links.
I'll keep looking.

bikeville said...

Hello,
we have mafac front hangers. $12 shipped(in USA) with ferrule. either for french or keyed English.

www.bikeville.com
not listed on the website, just email.

I love watching the progress on your bike.

RMHampel said...

bikeville,

I just saw your message. I'll be in touch.

Ron

steel said...

Perhaps I missed it, but am curious what type front cable hanger you decided on?

AH said...

Hi there -- actually, neither. The bike never "happened."

Anonymous said...

I know you had your heart set on that bike. Is there anyway of elaborating on the absence of "Clive"? Or maybe I just haven't reached it yet.

AH said...

Clive just plain didn't work out! And I am still working on getting a Clive-style bike...