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-   -   Titanium Brake Centerbolts (https://www.bikeforums.net/classic-vintage/1243663-titanium-brake-centerbolts.html)

Steel Charlie 12-13-21 02:38 PM

Titanium Brake Centerbolts
 
Doesn't seem as tho such a thing exists for single pivots, but that make much sense to me. I mean, what with all the other/everything titanium, why not centerbolts. In the grand scheme of WeightWeenieDom that's quite a chunk of weight.

inquiring minds, etc
Charlie

repechage 12-13-21 03:54 PM


Originally Posted by Steel Charlie (Post 22338927)
Doesn't seem as tho such a thing exists for single pivots, but that make much sense to me. I mean, what with all the other/everything titanium, why not centerbolts. In the grand scheme of WeightWeenieDom that's quite a chunk of weight.

inquiring minds, etc
Charlie

O.M.A.S. made a lightweight kit for Campagnolo Record original issue brakes, Ti centerbolt shaft, and aluminum pressed on spring backing barrel with lateral adjustment flats.
Lighter than a full ti pivot bolt.
Jim Merz has made full ti centerbolts, mostly or exclusively in the drop bolt style.

davester 12-13-21 08:32 PM

There's a guy in southern California who makes titanium drop bolts for Campy brakes. I know because I have one. I don't know if he makes straight bolts. He's on eBay somewhere.

Cyclist0108 12-13-21 08:44 PM

To answer the "why not?" question, a bolt of the same radius, etc., made of titanium instead of steel will be significantly weaker. A brake bolt would be low on my list for such a substitution.

repechage 12-13-21 08:53 PM

They do flex more.
long ago when I had a lathe I made one out of 6061 T6
rear only.
never broke
also made the eccentric cam part in aluminum
never bothered to weigh them but cool and no rust.
late Super Record pad holders were aluminum with steel studs- lighter, no rust.
hey, when one trains often along Pacific Coast Highway, no rust is appreciated.

Steel Charlie 12-14-21 03:29 PM

OK - Thanks all

Was just wondering

Charlie

Chombi1 12-14-21 05:25 PM

Are the Ti bolt threads cut or rolled?
Rolled threads will always be much more preferable, as it's less likely to crack......
I guess the real question is, can threads be rolled on to Ti bolts?

T-Mar 12-15-21 06:34 AM


Originally Posted by Chombi1 (Post 22340235)
Are the Ti bolt threads cut or rolled?
Rolled threads will always be much more preferable, as it's less likely to crack......
I guess the real question is, can threads be rolled on to Ti bolts?

Yes, you can roll threads into titanium. In fact, it is preferred due to the metal's high notch sensistivity.

T-Mar 12-15-21 06:36 AM

Here's the previously mentioned OMAS Ti brake bolt kit.

https://cimg2.ibsrv.net/gimg/bikefor...f4535c5f10.jpg

mpetry912 12-15-21 10:22 AM

it's Jim Merz, "PortlandJim" on ebay, and his stuff is top of the heap, really excellent.

right now he only offers Cinelli seat bolts, but other parts are available.

really top quality items.

/markp

styggno1 12-15-21 01:11 PM

By some deemed as unsafe but as with most things it depends on for what purpose. For a time trial bike where you might brake (more modulating speed than stopping) for a turn a couple of times...

Ergal and ti.

https://live.staticflickr.com/1836/4...67ac6c6_3k.jpg

ClydeClydeson 12-15-21 01:17 PM

Absolutely not.

Any part or fastener that is restricted to the geometry of the original steel part should not be replaced with titanium UNLESS it is a very low-load and non safety-related part. Waterbottle bolts? Sure. Brake mounting bolts? No.
If the part and mating components could be redesigned to use a larger bolt or part then yes, but simply swapping in the weaker material with no other mods on a safety related part (to save single digit grams) is a bad idea.

Fredo76 12-15-21 01:37 PM

Galli made a Criterium brake set with titanium center bolts in the late '70s/early 80s.

I like the drillium levers themselves, but lever effort is high, perhaps due to overly strong caliper springs?

styggno1 12-15-21 01:47 PM


Originally Posted by ClydeClydeson (Post 22341124)
Absolutely not.

Any part or fastener that is restricted to the geometry of the original steel part should not be replaced with titanium UNLESS it is a very low-load and non safety-related part. Waterbottle bolts? Sure. Brake mounting bolts? No.
If the part and mating components could be redesigned to use a larger bolt or part then yes, but simply swapping in the weaker material with no other mods on a safety related part (to save single digit grams) is a bad idea.

Again... It all depends for what purpose. There are a lot of things in life that depends. Here is a full blown time trial bike untouched since it was used in the early 70ies. By professionals. A lot of parts on this bike would not stand the use in a road race (ergal bits, 28 spoke wheels, etc.) but they chose to build it for TT racing. And it worked. And it did not fail. For what is was used for.

https://live.staticflickr.com/4852/3...64df236_3k.jpg

They even drilled the handlebars (can be seen in this picture if looking carefully).

https://live.staticflickr.com/4821/4...a7695f6_3k.jpg

I am not saying it is for everybody. I am saying it depends.

ClydeClydeson 12-15-21 02:05 PM

styggno1 Thanks for that, but proof that is has been done is not proof that it was ever a good idea. Pros used to use cocaine and strychnine as PEDs, and those also are not a good idea if you value your physical well being.

styggno1 12-15-21 02:12 PM


Originally Posted by ClydeClydeson (Post 22341187)
styggno1 Thanks for that, but proof that is has been done is not proof that it was ever a good idea. Pros used to use cocaine and strychnine as PEDs, and those also are not a good idea if you value your physical well being.

OK. I guess you know better. Thanks.

Drillium Dude 12-15-21 03:14 PM


Originally Posted by ClydeClydeson (Post 22341124)
Absolutely not. Any part or fastener that is restricted to the geometry of the original steel part should not be replaced with titanium UNLESS it is a very low-load and non safety-related part. Waterbottle bolts? Sure. Brake mounting bolts? No.
If the part and mating components could be redesigned to use a larger bolt or part then yes, but simply swapping in the weaker material with no other mods on a safety related part (to save single digit grams) is a bad idea.

Real-world experience trumps speculation; 2010:

https://cimg3.ibsrv.net/gimg/bikefor...ef2a483813.png

2018:

https://cimg3.ibsrv.net/gimg/bikefor...b776533383.png

The bike in question went through every kind of punishment imaginable; Cino 2014:

https://cimg8.ibsrv.net/gimg/bikefor...a8f7d5618d.png

Braking is absolutely confidence-inspiring or I wouldn't continue to use them - as I fully intend to do.

DD

52telecaster 12-15-21 03:17 PM

I have titanium crank fixing bolts one one crank. They seem to work fine but I pretightened with steel ones first.


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