Framebuilders - Disc tabs on vintage fork?

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xtrajack
07-06-10, 02:45 PM
Hello, all,
I don't know if this is the right place to ask this, is it possible to have disc tabs added to a vintage fork?
Backstory:
I have a nice steel framed vintage bike, that I would like to be a donor for an Xtracycle build.
The existing fork doesn't have disc tabs. I have become a real big disc brake fan. The existing fork is 1" threaded, so buying a replacement fork with disc tabs doesn't seem to be an option.
Thank you for your response.
bobbycorno
07-06-10, 03:05 PM
I'm no expert, but from what I've heard the fork is probably not strong/rigid enough for the stresses of a disk brake. I'd ask a professional framebuilder.
SP
Bend, OR
Disk forks are built to withstand the different braking forces that disks provide.
Welding disk tabs on a non-disk fork results in failure where the fork leg folds backward at the top of the disk tab. I experienced this recently.
xtrajack
07-06-10, 03:21 PM
Disk forks are built to withstand the different braking forces that disks provide.
Welding disk tabs on a non-disk fork results in failure where the fork leg folds backward at the top of the disk tab. I experienced this recently.
I was afraid that it would turn out to be something like that, but, Hope springs eternal.
I guess that I would have to find a frame builder and see if I could have a custom made fork. Probably would be cost prohibitive.
I was afraid that it would turn out to be something like that, but, Hope springs eternal.
I guess that I would have to find a frame builder and see if I could have a custom made fork. Probably would be cost prohibitive.
http://www.ebikestop.com/dimension_cross_fork_with_disc_mount_1_threadless_black_no_cantilever_bosses-FK1268.php
+
a new 1 inch threadless headset will probably be far cheaper than custom if the other fork dimensions/geometry work
unterhausen
07-06-10, 09:15 PM
I'm told this part (http://www.paragonmachineworks.com/storename/paragonmachineworks/dept/261299/ItemDetail-10464122.aspx) will keep the fork blade from un-raking. You bend the long part around the rake of the blade
I always hate to see the words "nice steel vintage bike" along with plans of radical modifications. I guess it depends on what kind of bike it really is.
fietsbob
07-07-10, 12:09 AM
Consider a Drum brake front hub instead, More progressive, all weather braking, and no modifications needed.
just a band that wraps around the fork-blade 6 inches up, for the reaction strut.
I'd still be afraid the crown would fail with even the pragon part.
fietsbob
07-07-10, 03:38 PM
Getting away from discs, I've been Using a Tange sloping crown fork, 80's era
on the Stumpjumper rescue frame project winter bike,
Riding it for Many Years, No problems , My drum Brake hubs have been trouble free for 20 years.. shoes don't wear out ..
taking a page from history , you could have a bracing strut added from the dropout to the top of the fork steerer, that what Motorcycles did , back in the day.
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