Bent fork - Frame and headset damage?
#1
Thread Starter
Buddy
Joined: Aug 2007
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From: Toronto
Bikes: 80s Gardin. Green fixed-gear. POS mountain bike.
Bent fork - Frame and headset damage?
How can you tell if a frame and headset are damaged?
Big damage, dimples etc...are obvious. I have a steel bike and the steeling is a bit off, not easy to ride hands-free, and the fork seems slightly bent.
I hoping a replacement fork will fix the problem. How can you tell if there is a deeper problem with the frame and headset?
Thanks
Big damage, dimples etc...are obvious. I have a steel bike and the steeling is a bit off, not easy to ride hands-free, and the fork seems slightly bent.
I hoping a replacement fork will fix the problem. How can you tell if there is a deeper problem with the frame and headset?
Thanks
#2
The only real way to tell is to take it apart and have a frame builder put it on the jig and check it.
Other than that, you'll just have to see if you are happy with the way it rides no hands once you replace the fork.
Other than that, you'll just have to see if you are happy with the way it rides no hands once you replace the fork.
#3
Thread Starter
Buddy
Joined: Aug 2007
Posts: 684
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From: Toronto
Bikes: 80s Gardin. Green fixed-gear. POS mountain bike.
Thanks, that's what I'll do. It appears as though one side of the fork is bent back, I'm hoping it wasn't a strong collision. The bed isn't too obvious. I'm just hoping that it's possible that the fork is bend without it having affected the rest of the frame.
#4
Calamari Marionette Ph.D
Joined: Dec 2013
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From: Coeur d' Alene
Bikes: 3 Chinese Gas Pipe Nerdcycles and 2 Chicago Electroforged Boat Anchors
Look on the underside of the down tube. Look at it near where it meets the head tube. Look for wrinkles in the paint and indentations. Run your hand over it and feel for distortion in the tube.
#5
Old fart



Joined: Nov 2004
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From: Appleton WI
Bikes: Several, mostly not name brands.
The "string test" will tell you if the rear triangle is in alignment with the rest of the frame. A shop tool like the Park FT-4 can check for fork blade alignment.

And eye-balling the head tube against the seat tube may show if the head tube is out-of-axis with the seat tube.
When in doubt, take it to someone with an actual surface plate or alignment table to get it checked professionally.

And eye-balling the head tube against the seat tube may show if the head tube is out-of-axis with the seat tube.
When in doubt, take it to someone with an actual surface plate or alignment table to get it checked professionally.
#6
I had a bike a while ago that I could never quite get he headset in adjustment. It was like there was a sweet spot straight ahead, then it became tight when turning the bars.
Recently I've started wondering if that was a sign of hidden damage.
Recently I've started wondering if that was a sign of hidden damage.
#7
Senior Member
Joined: Apr 2009
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From: Boulder County, CO
Bikes: '92 22" Cannondale M2000, '92 Cannondale R1000 Tandem, another modern Canndondale tandem, Two Holy Grail '86 Cannondale ST800s 27" (68.5cm) Touring bike w/Superbe Pro components and Phil Wood hubs. A bunch of other 27" ST frames & bikes.
I took a bent fork to Mark Nobillette. He bent it back, checked it out, and charged a very reasonable fee. Peace of mind is priceless.
#8
Senior Member
Joined: Apr 2015
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From: Morris County, NJ
Bikes: 90's Bianchi Premio, Raleigh-framed fixed gear, Trek 3500, Centurion hybrid, Dunelt 3-spd, Trek 800
Could this have been due to "indexed" head tube bearings? I overhauled a head tube recently because the steering felt slightly notchy. Examining the races, I saw evenly spaced shiny spots. After cleaning and re-greasing, and replacing the ball bearings, everything seems fine. (I showed the races to an LBS mechanic who also thought they were salvageable.)
#9
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Joined: Aug 2005
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From: Pittsburgh, PA
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
Or it was evidence that the faces of the headtube weren't parallel. Facing the headtube might have eliminated the problem.
#10
Could this have been due to "indexed" head tube bearings? I overhauled a head tube recently because the steering felt slightly notchy. Examining the races, I saw evenly spaced shiny spots. After cleaning and re-greasing, and replacing the ball bearings, everything seems fine. (I showed the races to an LBS mechanic who also thought they were salvageable.)
The lower headset crown race on my Colnago is getting pretty badly washboarded, but it doesn't seem to affect the steering. I should probably either polish the crown race, or replace it. Maybe for the next rebuild.
#11
That may have been it too. Or, perhaps a combination of problems. I think one bike that had touchy steering had been powdercoated prior to my getting it.
#12
Thread Starter
Buddy
Joined: Aug 2007
Posts: 684
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From: Toronto
Bikes: 80s Gardin. Green fixed-gear. POS mountain bike.
I'm going to change the fork, replace bearings, and hope that it feels good. Taking it to a frame builder or another expert is a possibility since I really like the bike.
Anybody know if there is someone good with frames in Toronto? I haven't come across anything yet.
Anybody know if there is someone good with frames in Toronto? I haven't come across anything yet.








