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Old 03-15-14, 09:58 AM   #1
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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.

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Old 03-15-14, 10:02 AM   #2
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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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Old 03-15-14, 10:38 AM   #3
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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
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Old 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.
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Old 03-15-14, 01:57 PM   #5
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Curiously, "Fork Bending Tool" was my nickname in highschool

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Old 03-15-14, 02:06 PM   #6
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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.
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Old 03-15-14, 02:17 PM   #7
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Curbs and potholes are about as easy as it gets for fork bending.
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Old 03-15-14, 03:59 PM   #8
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Originally Posted by rootboy View Post
Necessity is the mother..

Great stuff, Big Ring. Tell us more. How the fork blade was bent, and how you applied the pressure, etc.
After discovering the brake pad problem and noting the huge curve of the fork I googled Moto grand record and came up with a picture of the bike i bought on ebay. I'm guessing this bike may have gone through a couple owners till it was put on ebay. Who knows. As you can see the fork has/had a whopping curve to it.

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.
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Old 03-15-14, 06:20 PM   #9
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I had a rim unbender that doubled as a garage door.
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