Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Head tube crack - Repairable?

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

Head tube crack - Repairable?

Old 11-20-07, 02:27 PM
  #1  
bcart1991
Hip to the Game.
Thread Starter
 
bcart1991's Avatar
 
Join Date: Jul 2007
Location: Cracklanta, GA
Posts: 408

Bikes: Kona Lava Dome, Kapu 853

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Head tube crack - Repairable?

Upon pressing in a headset, the head tube of one of my frames developed a crack. It's not terribly large (approx. 1/4" long), starting at the bottom of the tube, on the front side (basically looking straight forward).

The frame is aluminum, so I'm wondering if this would be repairable by a competent welder, who could potentially fill in the crack, and grind/sand the tube smooth/round.

No chance at a warranty or replacement.

Thoughts?

Kotter
bcart1991 is offline  
Old 11-20-07, 03:06 PM
  #2  
Svr
Senior Member
 
Svr's Avatar
 
Join Date: Dec 2005
Location: Atlanta, GA
Posts: 1,223
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
While it's possible to weld the crack, it's likely the head tube will crack again, probably next to where it was welded. It would be a temporary and somewhat risky fix at best.
Svr is offline  
Old 11-20-07, 03:20 PM
  #3  
bcart1991
Hip to the Game.
Thread Starter
 
bcart1991's Avatar
 
Join Date: Jul 2007
Location: Cracklanta, GA
Posts: 408

Bikes: Kona Lava Dome, Kapu 853

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
That's what I was thinking. I'll be keeping a close eye on it. It should be rideable until I find a suitable replacement.
bcart1991 is offline  
Old 11-20-07, 03:34 PM
  #4  
kenhill3
use your best eye
 
kenhill3's Avatar
 
Join Date: Mar 2006
Location: Olympia, Washington
Posts: 3,050

Bikes: '75 Bertin, '93 Parkpre Team 925, '04 Kona King Kikapu, '05 Bianchi Vigorelli

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Not reliably repairable. My condolences.

Your frame has 'ceased to be'. It is an 'ex-frame'.
__________________
"I tell you, We are here on earth to fart around, and don't let anybody tell you any different." - Kurt Vonnegut jr.
kenhill3 is offline  
Old 11-20-07, 04:03 PM
  #5  
blamp28
Bikaholic
 
blamp28's Avatar
 
Join Date: Dec 2006
Location: Western, Michigan
Posts: 1,461

Bikes: Trek Fuel 90, Giant OCR, Rans Screamer Tandem

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by bcart1991 View Post
It should be ride able until I find a suitable replacement.
This crack could result in a sudden failure. Having the fork come out at an inopportune time can be very bad. Would you be so kind as to name my as a beneficiary on your life insurance? Really though, I would not ride it at all but I like to err on the side of caution.
blamp28 is offline  
Old 11-20-07, 07:13 PM
  #6  
dvs cycles
Senior Member
 
Join Date: Oct 2007
Location: SoCal
Posts: 1,169
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by bcart1991 View Post
Upon pressing in a headset, the head tube of one of my frames developed a crack. It's not terribly large (approx. 1/4" long), starting at the bottom of the tube, on the front side (basically looking straight forward).

The frame is aluminum, so I'm wondering if this would be repairable by a competent welder, who could potentially fill in the crack, and grind/sand the tube smooth/round.

No chance at a warranty or replacement.

Thoughts?

Kotter
I had that happen on a brand new Serotta in '92 I thought but it turned out to be just the paint and not metal.
Are you sure it is the actual tube? Just asking, if youve pulled the race to check or can actually see the depth sorry to hear it. I always hope for the superficial first.
dvs cycles is offline  
Old 11-20-07, 09:26 PM
  #7  
Sheldon Brown
Gone, but not forgotten
 
Sheldon Brown's Avatar
 
Join Date: Jul 2002
Location: Newtonville, Massachusetts
Posts: 2,301

Bikes: See: http://sheldonbrown.org/bicycles

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 13 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by bcart1991 View Post
Upon pressing in a headset, the head tube of one of my frames developed a crack. It's not terribly large (approx. 1/4" long), starting at the bottom of the tube, on the front side (basically looking straight forward).

The frame is aluminum...
If you're going to keep riding it, it would be a good idea to drill a small (3/16"?) hole just where the crack ends. This will stop the sharp end of the crack from acting as a stress riser. If you don't do that, the crack is liable to grow.

The poster who wrote "This crack could result in a sudden failure." is a well-meaning alarmist. The location of the crack means that it is mainly stressed in static weight bearing. It carries no share of braking load.

If the problem does get worse (the crack grows) it will give you plenty of warning. It will feel as if the headset is misadjusted (too loose) LOOOOOOONG before there's any chance of "sudden failure."

Sheldon "Seen This Before" Brown
Sheldon Brown is offline  
Old 11-20-07, 10:53 PM
  #8  
kenhill3
use your best eye
 
kenhill3's Avatar
 
Join Date: Mar 2006
Location: Olympia, Washington
Posts: 3,050

Bikes: '75 Bertin, '93 Parkpre Team 925, '04 Kona King Kikapu, '05 Bianchi Vigorelli

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Sheldon, thank you for your knowledge and real experience, it is very much appreciated.

You rock, dude!
__________________
"I tell you, We are here on earth to fart around, and don't let anybody tell you any different." - Kurt Vonnegut jr.
kenhill3 is offline  
Old 11-21-07, 06:59 AM
  #9  
blamp28
Bikaholic
 
blamp28's Avatar
 
Join Date: Dec 2006
Location: Western, Michigan
Posts: 1,461

Bikes: Trek Fuel 90, Giant OCR, Rans Screamer Tandem

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Sheldon Brown View Post
If you're going to keep riding it, it would be a good idea to drill a small (3/16"?) hole just where the crack ends. This will stop the sharp end of the crack from acting as a stress riser. If you don't do that, the crack is liable to grow.

The poster who wrote "This crack could result in a sudden failure." is a well-meaning alarmist. The location of the crack means that it is mainly stressed in static weight bearing. It carries no share of braking load.

If the problem does get worse (the crack grows) it will give you plenty of warning. It will feel as if the headset is misadjusted (too loose) LOOOOOOONG before there's any chance of "sudden failure."

Sheldon "Seen This Before" Brown

I stand corrected. "well-meaning alarmist"? Guilty as charged. I always prefer to err on the side of caution on things like this. Good point on the drilled hole to mitigate a stress riser.
blamp28 is offline  
Old 11-21-07, 07:15 AM
  #10  
Chris0381
Member
 
Join Date: Oct 2007
Posts: 48
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Any possibility of putting a hose clamp or clamps around the head tube to reinforce.
Chris0381 is offline  
Old 11-21-07, 07:38 AM
  #11  
bcart1991
Hip to the Game.
Thread Starter
 
bcart1991's Avatar
 
Join Date: Jul 2007
Location: Cracklanta, GA
Posts: 408

Bikes: Kona Lava Dome, Kapu 853

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Drilling the hole is a good idea. I can *just* see the HS race through the crack in the right light, so I know it's not just paint. My LBS concurred, and has also pretty much givent eh same words of wisdom here, save the "well-meaning-alarmist."

I know it's not a stress-bearing area, so it wil be okay for a while.

I actually thought about a hose clamp, but there's not enough space to fit it in there.

Thanks for all the advice everyone.

Kotter
bcart1991 is offline  
Old 11-21-07, 11:36 AM
  #12  
a77impala
a77impala
 
a77impala's Avatar
 
Join Date: Oct 2005
Location: Western South Dakota
Posts: 1,505
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 21 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Is the tube long enough so you could cut it off at the point of the crack? A quarter inch shouldn't change the dynamics of the frame a noticable amount.
a77impala is offline  
Old 11-21-07, 01:05 PM
  #13  
bcart1991
Hip to the Game.
Thread Starter
 
bcart1991's Avatar
 
Join Date: Jul 2007
Location: Cracklanta, GA
Posts: 408

Bikes: Kona Lava Dome, Kapu 853

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
The frame is a 52, so not much wiggle room.
bcart1991 is offline  
Old 11-21-07, 01:21 PM
  #14  
dobber
Perineal Pressurized
 
dobber's Avatar
 
Join Date: Oct 2003
Location: In Ebritated
Posts: 6,555
Mentioned: 0 Post(s)
Tagged: 1 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
How about popping the bottom cup back out and then reinstalling it with the addition of some epoxy. Might serve as an additonal structural element to help hold it all together.
__________________
This is Africa, 1943. War spits out its violence overhead and the sandy graveyard swallows it up. Her name is King Nine, B-25, medium bomber, Twelfth Air Force. On a hot, still morning she took off from Tunisia to bomb the southern tip of Italy. An errant piece of flak tore a hole in a wing tank and, like a wounded bird, this is where she landed, not to return on this day, or any other day.
dobber is offline  
Old 11-21-07, 03:15 PM
  #15  
Chris0381
Member
 
Join Date: Oct 2007
Posts: 48
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
My last suggestion would be to weld a curved AL plate over it like patching a tire.
Chris0381 is offline  
Old 11-21-07, 03:33 PM
  #16  
EvilV
Bicycling Gnome
 
Join Date: Apr 2006
Location: 55.0N 1.59W
Posts: 1,877
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
If it isn't a stressed area, why did it crack in teh first place?
EvilV is offline  
Old 11-21-07, 04:04 PM
  #17  
powers2b
Listen to me
 
powers2b's Avatar
 
Join Date: Nov 2004
Location: Lexus Texas
Posts: 2,789
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Chris0381 View Post
My last suggestion would be to weld a curved AL plate over it like patching a tire.
Can't properly weld without heat treating the entire frame again.
powers2b is offline  
Old 12-07-07, 08:04 AM
  #18  
dirtbag214
Member
 
Join Date: Oct 2007
Posts: 37
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
does the word"measure" mean anything to you?,the pressed in cups are a "press fit".the cups cannot be more than.2mm bigger if they are you risk cracking the head tube!!!! this is a job for a professional bike machinic,not a home machinic.i have seen more bicycles destroyed this way. headset installation is the most dangerous to the bike if you don't know what your doing.
dirtbag214 is offline  
Old 12-07-07, 08:21 AM
  #19  
bcart1991
Hip to the Game.
Thread Starter
 
bcart1991's Avatar
 
Join Date: Jul 2007
Location: Cracklanta, GA
Posts: 408

Bikes: Kona Lava Dome, Kapu 853

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Again, but in English, please.

The frame was at the shop when it happened. Thanks for the input though, cockbite.
bcart1991 is offline  
Old 12-07-07, 11:39 AM
  #20  
Booger1
Senior Member
 
Join Date: Sep 2007
Location: Gaseous Cloud around Uranus
Posts: 3,738
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 31 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
As Sheldon said,drill a small hole at the end on the crack,that will stop the crack from getting worse.If there's room for it,you could make a small steel or aluminum ring and shink fit it on the head tube.If your lucky,you can make the ring so it covers the crack and the hole both.
Booger1 is offline  
Old 12-07-07, 08:43 PM
  #21  
gmorris
Senior Member
 
gmorris's Avatar
 
Join Date: Jul 2007
Location: Evansville IN
Posts: 52

Bikes: Cannondale CAAD5, Gary Fisher Montare

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Everybody seems to overstate the importance of heat treating aluminum before it's welded. I unfortunately have weld all day and trust me, on thin walled aluminum there is no need to preheat. Getting the paint off and the part clean woud be far more important. If your wanting a cosmeticly pleasing repain, don't weld it unless you're planning on repainting. You'll wind up boiling all the paint off at least 1.5" around the welded area.
Have you considered the possiblity of not being able to get the diameter of the head tube back to the original size? Sounds like you've managed to stretch it.
Good luck
gmorris is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
LeroyAchoy
General Cycling Discussion
2
03-08-07 10:03 AM
MoneyMaker
BMX
28
04-16-06 06:30 PM
Delix
Introductions
2
04-24-05 10:34 PM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.