Go Back  Bike Forums > Bike Forums > Framebuilders
Reload this Page >

Straighten a UO-8 steer tube?

Search
Notices
Framebuilders Thinking about a custom frame? Lugged vs Fillet Brazed. Different Frame materials? Newvex or Pacenti Lugs? why get a custom Road, Mountain, or Track Frame? Got a question about framebuilding? Lets discuss framebuilding at it's finest.

Straighten a UO-8 steer tube?

Thread Tools
 
Search this Thread
 
Old 11-11-09, 03:49 PM
  #1  
Senior Member
Thread Starter
 
Road Fan's Avatar
 
Join Date: Apr 2005
Location: Ann Arbor, MI
Posts: 16,874

Bikes: 1980 Masi, 1984 Mondonico, 1984 Trek 610, 1980 Woodrup Giro, 2005 Mondonico Futura Leggera ELOS, 1967 PX10E, 1971 Peugeot UO-8

Mentioned: 49 Post(s)
Tagged: 0 Thread(s)
Quoted: 1856 Post(s)
Liked 664 Times in 506 Posts
Straighten a UO-8 steer tube?

I guess I should have asked here first. I just got a UO-8 because I wanted to see how it's unusual front end geometry feels. Repairing the headset I found the steer tube is bent, enough that a good headset will show some binding. I know it is possible to replace a steer tube, but this is a CHEEP project. What do you guys think about straightening it? The bend is about 2 degrees max, not near the fork crown, and there is no sign of fork blade or frame damage or stress. The direction of the bend is the opposite of what I'd expect from a frontal collision anyway. The steel is in the low carbon/high carbon family, not 531 or CrMo.

What y'all think? Might it be safe? Should it be done with a torch? Any experience with such a repair?

I really want to keep the dimensions of the OEM fork. It has around 7 cm of rake, a very tight old-fashioned French bend at the end, and it's loooong to accommodate 32+ mm 27 inch tires with a fender. I doubt a modern replacement exists.
Road Fan is offline  
Old 11-11-09, 10:11 PM
  #2  
Randomhead
 
Join Date: Aug 2008
Location: Happy Valley, Pennsylvania
Posts: 24,396
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 3,696 Times in 2,517 Posts
I can't imagine that ending well. Steerers have been known to break. If the fork isn't bent, but the steerer is, that doesn't say good things about a repaired version. And finding a french steerer is not impossible, but probably not cheap.
unterhausen is offline  
Old 11-12-09, 01:22 PM
  #3  
Senior Member
Thread Starter
 
Road Fan's Avatar
 
Join Date: Apr 2005
Location: Ann Arbor, MI
Posts: 16,874

Bikes: 1980 Masi, 1984 Mondonico, 1984 Trek 610, 1980 Woodrup Giro, 2005 Mondonico Futura Leggera ELOS, 1967 PX10E, 1971 Peugeot UO-8

Mentioned: 49 Post(s)
Tagged: 0 Thread(s)
Quoted: 1856 Post(s)
Liked 664 Times in 506 Posts
Even with a 2 degree bend, and no large kink at the bend? Surprised rather soft steel is so fragile - this isn't CrMo, MnMo, or something air-hardened, and its really not aluminum.

I do understand the greater risk of injury in case of failure of this tube.
Road Fan is offline  
Old 11-12-09, 06:45 PM
  #4  
Senior Member
 
Join Date: Jul 2009
Location: Alberta,Canada.
Posts: 800
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by Road Fan
Even with a 2 degree bend, and no large kink at the bend? Surprised rather soft steel is so fragile - this isn't CrMo, MnMo, or something air-hardened, and its really not aluminum.

I do understand the greater risk of injury in case of failure of this tube.
Sent PM
ddez is offline  
Old 11-12-09, 10:32 PM
  #5  
Senior Member
Thread Starter
 
Road Fan's Avatar
 
Join Date: Apr 2005
Location: Ann Arbor, MI
Posts: 16,874

Bikes: 1980 Masi, 1984 Mondonico, 1984 Trek 610, 1980 Woodrup Giro, 2005 Mondonico Futura Leggera ELOS, 1967 PX10E, 1971 Peugeot UO-8

Mentioned: 49 Post(s)
Tagged: 0 Thread(s)
Quoted: 1856 Post(s)
Liked 664 Times in 506 Posts
While I appreciate volunteering opinions, I thought I was explicitly looking for those with experience in repairing frames.

I can theorize better than most. That isn't what I needed.

Thanks anyway.
Road Fan is offline  
Old 11-13-09, 01:31 AM
  #6  
Elitest Murray Owner
 
Mos6502's Avatar
 
Join Date: Apr 2006
Posts: 2,657

Bikes: 1972 Columbia Tourist Expert III, Columbia Roadster

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 3 Times in 2 Posts
Go ahead straighten it.
Mos6502 is offline  
Old 11-14-09, 01:08 PM
  #7  
Randomhead
 
Join Date: Aug 2008
Location: Happy Valley, Pennsylvania
Posts: 24,396
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 3,696 Times in 2,517 Posts
If my powers of deduction are up to snuff, he had a bike shop bend it and they ovalized the threads.

Originally Posted by unterhausen
I can't imagine that ending well.
Just because we post on BF doesn't mean we don't know what we are talking about.
unterhausen is offline  
Old 11-14-09, 09:13 PM
  #8  
Senior Member
Thread Starter
 
Road Fan's Avatar
 
Join Date: Apr 2005
Location: Ann Arbor, MI
Posts: 16,874

Bikes: 1980 Masi, 1984 Mondonico, 1984 Trek 610, 1980 Woodrup Giro, 2005 Mondonico Futura Leggera ELOS, 1967 PX10E, 1971 Peugeot UO-8

Mentioned: 49 Post(s)
Tagged: 0 Thread(s)
Quoted: 1856 Post(s)
Liked 664 Times in 506 Posts
Good work; I saw you there. Yes, they ovalized the end of the thread area, and I managed to squeeze it back round, at least round enough to insert the right stem and thread the headset parts on. I used a 14 inch channel-lock and a pair of wood buffers. It took about 15 squeezes, in several different directions. No added thread damage.

Plan is to assemble the fork to the frame, finish reassembling the bike, and do some smooth-road test rides, just a few hours. That will be enough to tell me if I like the bike and geometry, which is the main point of this whole project. If I do like the geometry, I'll get a replacement.

Update 1: The headset install feels pretty darn good! It adjusted correctly and spins freely 360 degrees.

Last edited by Road Fan; 11-16-09 at 05:25 PM.
Road Fan is offline  

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



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

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.