Bent steel fork?
#1
Thread Starter
Portland, OR, USA

Joined: Feb 2004
Posts: 1,626
Likes: 1
From: portland
Bikes: kona paddywagon, trek 2.1, lemond nevada city, gt zrx
Bent steel fork?
would you be able to tell if your fork was obviously bent. as it is, its not obvious in how the bike rides but i swear the top of the blades are back at a slightly steeper angle then they used to be. i was in a very stupid one person crash last week. sweeping thru a turn, i suffered a front tire sidewall blowout. the fork hit a tire and fork hit a barrier at a 90 degree angle but the only apparent damage (besides on me!) was the deflated tire and scraped up and turned left shifter. im not scared to ride it, its steel with a steel steerer but i just wonder if maybe the trail has been altered. how would you know? does it matter??
#2
would you be able to tell if your fork was obviously bent. as it is, its not obvious in how the bike rides but i swear the top of the blades are back at a slightly steeper angle then they used to be. i was in a very stupid one person crash last week. sweeping thru a turn, i suffered a front tire sidewall blowout. the fork hit a tire and fork hit a barrier at a 90 degree angle but the only apparent damage (besides on me!) was the deflated tire and scraped up and turned left shifter. im not scared to ride it, its steel with a steel steerer but i just wonder if maybe the trail has been altered. how would you know? does it matter??
Being in pdx there are lots of decent shops that could check this, my schedule is pretty tight right now but if you are around the se I could take a quick look at things.
You can send me a pm or email through the link on my website.
#3
Thread Starter
Portland, OR, USA

Joined: Feb 2004
Posts: 1,626
Likes: 1
From: portland
Bikes: kona paddywagon, trek 2.1, lemond nevada city, gt zrx
I think I am batting a thousand when it comes to picking out bent forks although slight bends may not show up in pictures.
Being in pdx there are lots of decent shops that could check this, my schedule is pretty tight right now but if you are around the se I could take a quick look at things.
You can send me a pm or email through the link on my website.
Being in pdx there are lots of decent shops that could check this, my schedule is pretty tight right now but if you are around the se I could take a quick look at things.
You can send me a pm or email through the link on my website.
#4
so any tips for eye-balling one? its a traditional raked road fork with a very shiny paint job. i took a bright light to see the reflection of the headtube centerline and fork centerline and they seemed to line up ok. maybe im hallucinating. however the toe overlap with the pedal seem more pronounced.
Take a picture from the side making sure you are square to the headtube and fork, also check the position of the front wheel to make sure it is lined up.
If you have time to swing by I work for coffee although I am not set up to make repairs here.
#5
Senior Member
Joined: Jul 2009
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Bikes: 1986 Alan Record Carbonio, 1985 Vitus Plus Carbone 7, 1984 Peugeot PSV, 1972 Line Seeker, 1986(est.) Medici Aerodynamic (Project), 1985(est.) Peugeot PY10FC
I always thry to see if the back sides of the fork legs are at least parallel to the steerer and/or head tube (when mounted on the frame).
#6
Thread Starter
Portland, OR, USA

Joined: Feb 2004
Posts: 1,626
Likes: 1
From: portland
Bikes: kona paddywagon, trek 2.1, lemond nevada city, gt zrx
that makes sense. so i took a picture of the post crash fork and used a straight edge to compare the angle of the steer tube and the back of the fork. id say the fork and tube are definitely parallel to the eye. maybe ill drop it into autocad and measure it that way.
Last edited by pdxtex; 08-26-13 at 02:27 PM.
#7
Senior Member


Joined: Apr 2009
Posts: 39,897
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From: New Rochelle, NY
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
It's very easy to spot a bent (curved blade) fork, and you only need one eye. Sight down along the like from the stem, past the head tube, and on to the blades, as if sighting a rifle. The upper part of the blades is always on that line, so if you see a change in alignement you know the fork is bent.
Straight blade forks can't ge gauged this way because they have the blades set at an angle to the axis so there's no reference.
Also a bent fork will often have a weird headset feel with it being tighter to one or both sides than straight on. You might also see a misalignment in the headset cups, either where the cups meet, or where they're pressed into the frame.
Some "bent forks" aren't bent at all, instead the impact bent the frame at the headstube. Look forripples or a buckle under the front of the down tube, or stretch marks in the paint at the top front of either the top or down tubes.
Experienced eyes, can often spot a bent frame or fork at a glance, because the front wheel is in the wrong place (too far back).
Straight blade forks can't ge gauged this way because they have the blades set at an angle to the axis so there's no reference.
Also a bent fork will often have a weird headset feel with it being tighter to one or both sides than straight on. You might also see a misalignment in the headset cups, either where the cups meet, or where they're pressed into the frame.
Some "bent forks" aren't bent at all, instead the impact bent the frame at the headstube. Look forripples or a buckle under the front of the down tube, or stretch marks in the paint at the top front of either the top or down tubes.
Experienced eyes, can often spot a bent frame or fork at a glance, because the front wheel is in the wrong place (too far back).
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Chain-L site
An ounce of diagnosis is worth a pound of cure.
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FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.





