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Date: 05 Sep 2007 14:53:50
From: DougA
Subject: Ti Fork?
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Any idea why this magic material has not been used for forks? Could it be
not stiff enough?
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Date: 05 Sep 2007 20:14:07
From:
Subject: Re: Ti Fork?
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On Wed, 05 Sep 2007 14:53:50 GMT, "DougA" <douga@hotmail.com > wrote:
>Any idea why this magic material has not been used for forks? Could it be
>not stiff enough?
It isn't magic.
It is used for forks.
Stick one in this troll, it's done.
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Date: 05 Sep 2007 14:57:50
From:
Subject: Re: Ti Fork?
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On Sep 5, 2:40 pm, Helmut Springer <delta+use...@lug-s.org > wrote:
> unforgive...@juno.com wrote:
> > The problem with making a lightweight road fork is that the crown
> > would have to be forged instead of welded, which is a real bitch
> > with titanium.
>
> Current Columbus EL forks are TIG welded unicrown, wouldn't that be
> an option for Ti as well?
>
> --
> MfG/Best regards
> helmut springer panta rhei
Welded unicrown is an option, but the narrower the tire clearance the
heavier it ends up compared to forged. Nothing about a titanium road
fork would be special enough to go over 100g heavier than carbon at a
significant cost penalty. On the mountain bike end, the Sibex fork is
one of the lightest out there.
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Date: 05 Sep 2007 13:11:27
From: russellseaton1@yahoo.com
Subject: Re: Ti Fork?
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On Sep 5, 11:43 am, bfd <bfd...@yahoo.com > wrote:
> On Sep 5, 7:53 am, "DougA" <do...@hotmail.com> wrote:
>
> > Any idea why this magic material has not been used for forks? Could it be
> > not stiff enough?
>
> That's pretty much it. If you make a ti fork as stiff as a steel or
> carbon, then its weighs a ton. I am not aware of any ti fork that is
> light enough to compete with carbon. I believe the lightest one I saw
> was like 500 or 600g, which is very heavy!
>
> I've recall an italian or eastern european mfr who use to make a ti
> frame and offered a ti fork.
Morati for the titanium fork.
The price for the frameset was insane,
> like $10,000, and that was back in the early 90s.
>
> If you really "gots to have one," I believe Calfee use to sell a ti
> fork for his cyclocross frame. You may want to contact him.
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Date: 05 Sep 2007 14:10:09
From: A Muzi
Subject: Re: Ti Fork?
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DougA wrote:
> Any idea why this magic material has not been used for forks? Could it be
> not stiff enough?
Been done many times; Speedwell, Teledyne, Panasonic Sumitomo Mory etc.
Steel may be a better choice but Ti is certainly possible. The jointing
techniques available at the crown aren't favorable to Ti.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
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Date: 05 Sep 2007 21:21:18
From: jim beam
Subject: Re: Ti Fork?
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A Muzi wrote:
> DougA wrote:
>> Any idea why this magic material has not been used for forks? Could
>> it be not stiff enough?
>
> Been done many times; Speedwell, Teledyne, Panasonic Sumitomo Mory etc.
> Steel may be a better choice but Ti is certainly possible. The jointing
> techniques available at the crown aren't favorable to Ti.
absolutely.
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Date: 05 Sep 2007 10:36:00
From:
Subject: Re: Ti Fork?
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On Sep 5, 12:43 pm, bfd <bfd...@yahoo.com > wrote:
> On Sep 5, 7:53 am, "DougA" <do...@hotmail.com> wrote:
>
> > Any idea why this magic material has not been used for forks? Could it be
> > not stiff enough?
>
> That's pretty much it. If you make a ti fork as stiff as a steel or
> carbon, then its weighs a ton. I am not aware of any ti fork that is
> light enough to compete with carbon. I believe the lightest one I saw
> was like 500 or 600g, which is very heavy!
>
> I've recall an italian or eastern european mfr who use to make a ti
> frame and offered a ti fork. The price for the frameset was insane,
> like $10,000, and that was back in the early 90s.
>
> If you really "gots to have one," I believe Calfee use to sell a ti
> fork for his cyclocross frame. You may want to contact him.
Stiffness isn't the issue. Sibex makes ti forks for cross and
mountain bikes
http://www.sibexsports.com/forks.htm
The cross fork is within 60g of Alpha Q's carbon cross fork, which is
even more expensive. The problem with making a lightweight road fork
is that the crown would have to be forged instead of welded, which is
a real bitch with titanium.
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Date: 05 Sep 2007 17:24:06
From: Donald Gillies
Subject: Re: Ti Fork?
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Actually, you could make a tubular fork crown easily and weld it, like
all raleigh 3-speeds made from 1920-1990. Mitering would be fairly
minimal. It seems like sibex hasn't exatly figured that out, yet ...
http://www.sibexsports.com/forks.htm
- Don Gillies
San Diego, CA
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Date: 05 Sep 2007 21:21:42
From: A Muzi
Subject: Re: Ti Fork?
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Donald Gillies wrote:
> Actually, you could make a tubular fork crown easily and weld it, like
> all raleigh 3-speeds made from 1920-1990. Mitering would be fairly
> minimal. It seems like sibex hasn't exatly figured that out, yet ...
>
> http://www.sibexsports.com/forks.htm
You should cut one in half sometime.
http://www.yellowjersey.org/THIMBLE.JPG
The Raleigh 'thimble fork' design relies on a deep dip-brazed internal
contact below the crown. A simple welded copy with reasonably light
material will fail as many hasty copies did.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
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Date: 06 Sep 2007 18:39:17
From: Michael Press
Subject: Re: Ti Fork?
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In article <13dup04m0scah55@corp.supernews.com >,
A Muzi <am@yellowjersey.org > wrote:
> Donald Gillies wrote:
> > Actually, you could make a tubular fork crown easily and weld it, like
> > all raleigh 3-speeds made from 1920-1990. Mitering would be fairly
> > minimal. It seems like sibex hasn't exatly figured that out, yet ...
> >
> > http://www.sibexsports.com/forks.htm
>
> You should cut one in half sometime.
> http://www.yellowjersey.org/THIMBLE.JPG
What is that round piece interior to the "crown?"
> The Raleigh 'thimble fork' design relies on a deep dip-brazed internal
> contact below the crown. A simple welded copy with reasonably light
> material will fail as many hasty copies did.
--
Michael Press
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Date: 06 Sep 2007 13:56:25
From: A Muzi
Subject: Re: Ti Fork?
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>> Donald Gillies wrote:
>>> Actually, you could make a tubular fork crown easily and weld it, like
>>> all raleigh 3-speeds made from 1920-1990. Mitering would be fairly
>>> minimal. It seems like sibex hasn't exatly figured that out, yet ...
>>> http://www.sibexsports.com/forks.htm
> A Muzi <am@yellowjersey.org> wrote:
>> You should cut one in half sometime.
>> http://www.yellowjersey.org/THIMBLE.JPG
Michael Press wrote:
> What is that round piece interior to the "crown?"
> A Muzi <am@yellowjersey.org> wrote:
>> The Raleigh 'thimble fork' design relies on a deep dip-brazed internal
>> contact below the crown. A simple welded copy with reasonably light
>> material will fail as many hasty copies did.
Remember the small cute Raleigh decals "The All Steel Bicycle"? Raleigh
developed pressed steel bottom brackets, lugs and crowns to replace the
prior sand-cast iron fittings (CCM for example was still using cast iron
BBs through the 1950s)
The famous 'thimble crown' looks as if the fork blades are tenuously
hanging from a horizontal pipe. In fact the outer piece slips deep into
the blades, the column goes right through that and there's another steel
liner inside, as you note. These are rumored to be 'dip brazed' and the
Raleigh salesmen pushed that 'feature' but despite searching I saw no
such operation at Nottingham in 1973. Who knows?
It is rare to see one of these forks fail for any reason including
second and third crashes after repeated alignments. I've never seen one
with a brazing error, although Nottingham Raleighs in general have about
the same rate as other Euro mass-market frames. Seat stay tops, mostly:
http://www.yellowjersey.org/fixstay.html
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
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Date: 05 Sep 2007 18:40:17
From: Helmut Springer
Subject: Re: Ti Fork?
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unforgiven99@juno.com wrote:
> The problem with making a lightweight road fork is that the crown
> would have to be forged instead of welded, which is a real bitch
> with titanium.
Current Columbus EL forks are TIG welded unicrown, wouldn't that be
an option for Ti as well?
--
MfG/Best regards
helmut springer panta rhei
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Date: 05 Sep 2007 09:43:04
From: bfd
Subject: Re: Ti Fork?
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On Sep 5, 7:53 am, "DougA" <do...@hotmail.com > wrote:
> Any idea why this magic material has not been used for forks? Could it be
> not stiff enough?
That's pretty much it. If you make a ti fork as stiff as a steel or
carbon, then its weighs a ton. I am not aware of any ti fork that is
light enough to compete with carbon. I believe the lightest one I saw
was like 500 or 600g, which is very heavy!
I've recall an italian or eastern european mfr who use to make a ti
frame and offered a ti fork. The price for the frameset was insane,
like $10,000, and that was back in the early 90s.
If you really "gots to have one," I believe Calfee use to sell a ti
fork for his cyclocross frame. You may want to contact him.
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