Mattias Hellöre Ax Lightness Brake Powercordz bolts

Discuss light weight issues concerning road bikes & parts.
Post Reply
sedluk
Posts: 409
Joined: Mon Sep 07, 2009 3:10 am

by sedluk

I have been trying out some bolts that I bought from Mattias Hellöre. Mattias Hellöre is a regular here and has made some interesting and special parts for people.

The original Ax Lightness bolts that are included with each brakeset do a good job at securing a steel brake cable but they need some special work to hold a Powercorz cable. You have to drill out the hole that the cable fits through and do a little dremel work so that the cylindrical part has a better bite. Then you tie a knot at the bottom of the cylindrical part so that the Powercordz does not get sucked into the little cylindrical part. It is not a very elegant solution so people look for aftermarket bolts. BTP made a few of them and still has them listed on their web site, in fact they are still listed as “New”. Good luck buying them, I am not sure what kind of things they are making, but $20 bolts is not one of them.

Mattias Hellöre came up with his solution. It does not have the grub screw like the BTP part but it has a raised edge so that the bolt does not slip out of the brake. I have never had a bolt slip out while riding but very rarely it can happen when traveling. I think this is a nice feature.

I spent some time thinking about the best way to tie the knot that would secure the cable and what I came up with is called an Arbor Knot. What I did first was smooth out the openings on the bolt. Mattias has already machined them a little but I wanted to make sure that the cable would not be cut by the corner where the Powercordz cable comes out of the bolt at a sharp angle.

I was out in California riding the Levi Gran Fondo and it really put everyone’s brakes to the test. The descent down Kings Ridge is a real pad burner and at times hits 20% for a while with something like 1,600 ft of descent.

The Arbor Knot tightened up just like it is supposed to and I have included a picture.

Image
Image

User avatar
Mattias Hellöre
in the industry
Posts: 554
Joined: Fri Sep 23, 2005 6:34 pm
Location: Insjön, SWEDEN
Contact:

by Mattias Hellöre

Thanks for the writeup!
But credits should ge given to Gumgardner and Andy2, they gave me neccessary measurements and I drawn up the part and got it machined.

Have done carbon ones for Gumgardner, very light but could be lighter as the grub screws and aluminum tube inside wasn´t needed.
Experimental Prototype

by Weenie


User avatar
mythical
Posts: 1489
Joined: Fri Apr 04, 2008 2:49 am
Location: Europe
Contact:

by mythical

Bolts? Where are they? I see only a cable tied in a knot. Better not have that come loose in a fast decent, then again, ships have managed sailing the seven seas over the past thousands of years with ropes that have knots, so it's probably safe enough on a brake. Well done, Swedes (and non-Swede)! ;)

Although I'd be concerned about that particular brand of brake. :roll:
“I always find it amazing that a material can actually sell a product when it’s really the engineering that creates and dictates how well that material will behave or perform.” — Chuck Teixeira

RideWert.com
Wert Cycling on Facebook

User avatar
prendrefeu
Posts: 8609
Joined: Wed Oct 31, 2007 10:32 pm
Location: Los Feliz, Los Angeles, California
Contact:

by prendrefeu

Question, gents:

If the Arbor Knot is so strong, and it looks like it is, why couldn't you just tie the knot on the underside of the barrel-bolt and just have the Powercord(z) pass through once?

I'm asking because those of us with the Planet-X / Featherlite type brakes have a similar mechanism for cable pull on the brake, but it is not as wide of an opening on the AX Lightness, so the cord can only pass through once. Why not just tie the knot at the bottom beneath the bolt and call it a day? Will the cord slip loose?
Exp001 || Other projects in the works.

PowerCordz
in the industry
Posts: 36
Joined: Tue Aug 30, 2011 7:27 pm

by PowerCordz

When the cord is tightened around itself, it is strong! Over 80K cycles on this knot, still counting....
Image
Last edited by PowerCordz on Tue Oct 16, 2012 5:00 pm, edited 1 time in total.

User avatar
prendrefeu
Posts: 8609
Joined: Wed Oct 31, 2007 10:32 pm
Location: Los Feliz, Los Angeles, California
Contact:

by prendrefeu

I see that the knots both from Powercordz and used in this thread for Mattias Hellöre's solution wrap around the bolt, then back through.

This isn't really possible with the Featherlite/Planet-X brakes: the bolt is very small and the opening on the cam mechanism looks to only be wide enough for one line of cable.

Can either of you or anyone here come up with a decent solution?

Pics:
Image
Image
Image
Image
Exp001 || Other projects in the works.

User avatar
pritchet74
Posts: 1315
Joined: Tue May 30, 2006 10:38 pm
Location: NorCal

by pritchet74

Here's the BTP one that I had on my bike for a comparison:
Image
Have you ever wondered if there was more to life, other than being really, really, ridiculously good looking?

artray
Posts: 1365
Joined: Fri Oct 07, 2011 2:08 pm

by artray

I have Planet x brakes on my trek . I use the KCNC teflon cables they weigh 14grms so not to bad.
To use powercordz prendrefeu and myself would need someone out there to make a new part of the brake so we could use powercordz .
Mattias Hellöre could you help? . A small carbon section would be awesome and drop the weight some more .

User avatar
Mattias Hellöre
in the industry
Posts: 554
Joined: Fri Sep 23, 2005 6:34 pm
Location: Insjön, SWEDEN
Contact:

by Mattias Hellöre

A carbon rod with a drilled hole in center?
But make a thread in a carbon rod is not a good idea, the bolt will strip immediately, maybe a another way?

Let me know how you want it.

Added a pic on Gumgardners brake bolts I did.
dsc1260b.jpg


Alu center pipe with grub screws not needed so deduct 0.5-1g from the total.
AX brake bolt 03.jpg
Experimental Prototype

artray
Posts: 1365
Joined: Fri Oct 07, 2011 2:08 pm

by artray

What about if the cordz goes round the bolt and up .Then wrapped around some kind of pinch bolt attached to the cable. ?

User avatar
Mattias Hellöre
in the industry
Posts: 554
Joined: Fri Sep 23, 2005 6:34 pm
Location: Insjön, SWEDEN
Contact:

by Mattias Hellöre

artray wrote:What about if the cordz goes round the bolt and up .Then wrapped around some kind of pinch bolt attached to the cable. ?


I thought about the same, let me know when you want one in mail or PM.
Experimental Prototype

by Weenie


artray
Posts: 1365
Joined: Fri Oct 07, 2011 2:08 pm

by artray

Thanks Mattias . KCNC have just released some new cables 7grm and 11grm . I think this now is the best option as a extra bolt with the Cordz will end up at about the same weight

http://clee-cycles.co.uk/esite/P18503/product" onclick="window.open(this.href);return false;

:beerchug:

Post Reply
  • Similar Topics
    Replies
    Views
    Last post