Fork bending tool
03-15-14, 09:58 AM
#1
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Thread Starter
Fork bending tool
My Motobecane Grand Record, 1980ish edition was delivered yesterday. It was an ebay purchase at a darn good price. To my delight it was in very good condition. Some nicks and scratches, but for a 30+ yr old bike, not bad.
Big problem I noticed was the front brake pads were below the rim when the pads were adjusted to the top of their adjustment. Looked at the fork and I thought, hmmm... looks like someone was pulling wheelies and landing them hard.
Soooo..... made due with an improvised fork bending tool. It worked. Bike rides straight. Fork is still not the most graceful of bends but only I will notice.
Big problem I noticed was the front brake pads were below the rim when the pads were adjusted to the top of their adjustment. Looked at the fork and I thought, hmmm... looks like someone was pulling wheelies and landing them hard.
Soooo..... made due with an improvised fork bending tool. It worked. Bike rides straight. Fork is still not the most graceful of bends but only I will notice.
03-15-14, 10:02 AM
#2
Senior Member
And I thought it was a weight bench. I have passed up many of fork bending tools at the resale shops and never even knew. 
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My bikes: 1970`s Roberts - 1981 Miyata 912 - 1980`s Ocshner (Chrome) - 1987 Schwinn Circuit - 1987 Schwinn Prologue - 1992 Schwinn Crosspoint - 1999 Schwinn Circuit - 2014 Cannondale Super Six EVO
My bikes: 1970`s Roberts - 1981 Miyata 912 - 1980`s Ocshner (Chrome) - 1987 Schwinn Circuit - 1987 Schwinn Prologue - 1992 Schwinn Crosspoint - 1999 Schwinn Circuit - 2014 Cannondale Super Six EVO
03-15-14, 10:38 AM
#3
Senior Member
There is always the self proclaimed 'redneck' method if you don't have a weight bench/clothes holder available.
How to straighten a bent bicycle fork - YouTube
How to straighten a bent bicycle fork - YouTube
03-15-14, 12:31 PM
#4
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Most important thing when bending fork blades or stays is to have a reference point from which to measure the progress during bending.
The opposite-side fork blade or chainstay can provide such reference, as long as it is not being subjected to any loads during the straightening.
Blocks of wood can prevent the localized loading that might dent tubing or cause too much localization in the bend location.
You can sight across the side profile view of the fork to determine what is needed to make the fork blades parallel and with identical shape/bend profile.
The opposite-side fork blade or chainstay can provide such reference, as long as it is not being subjected to any loads during the straightening.
Blocks of wood can prevent the localized loading that might dent tubing or cause too much localization in the bend location.
You can sight across the side profile view of the fork to determine what is needed to make the fork blades parallel and with identical shape/bend profile.
03-15-14, 01:57 PM
#5
surly old man
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Curiously, "Fork Bending Tool" was my nickname in highschool
jim
jim
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Cross Check Nexus7, IRO Mark V, Trek 620 Nexus7, Karate Monkey half fat, IRO Model 19 fixed, Amp Research B3, Surly 1x1 half fat fixed, and more...
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SB forever
03-15-14, 02:06 PM
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Necessity is the mother..
Great stuff, Big Ring. Tell us more. How the fork blade was bent, and how you applied the pressure, etc.
Great stuff, Big Ring. Tell us more. How the fork blade was bent, and how you applied the pressure, etc.
03-15-14, 02:17 PM
#7
Still learning
Curbs and potholes are about as easy as it gets for fork bending. 
03-15-14, 03:59 PM
#8
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Thread Starter
The wheelbase before I worked my magic was 41". Now it is 40", which would be typical for this bike, I would think.
The "technique' was simple. I wrapped hockey tape around the fork to protect it. Inserted the fork into the holes in my weight bench and leaned into it a bit. Then eyeballed it. Then test fit the wheel to make sure everything was square and centered. The bike still has a slight pull to the left. But can be ridden no hands with a bit of butt english. Probably needs the forkends aligned.
03-15-14, 06:20 PM
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I had a rim unbender that doubled as a garage door.
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