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Panther split fork Problem

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This is crazy. So the fork legs and everything else were not bent?

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This is crazy. So the fork legs and everything else were not bent?

View attachment 2027519
Your correct in being skeptical. My guess is this is what was remaining from a "partial repair" after a major hit.

In all of my years as a dealer, then a Schwinn employee, then a dealer again, I have never seen a spring fork stem that was bent like that. Including the ones that a car backed over. Defects do in fact get past the factory inspectors, but it would not have passed a dealer's test ride. It had to have a "major pull". You could not bend that part without bending a good deal of the other spring fork parts.

John
 
It looks to me like forks are bent. I did collision work for 40 years. It looks like it was a side hit on right side at wheel. So when forks are pushed from right to left, it has the opposite affect at the top. Thus the big gap at the spring.
 
It looks to me like forks are bent. I did collision work for 40 years. It looks like it was a side hit on right side at wheel. So when forks are pushed from right to left, it has the opposite affect at the top. Thus the big gap at the spring.

I see where you're coming from, so let's assign some "car part names" to the bicycle parts and see if that changes anything.

The Spring Fork legs compare to a cars Suspension A-Frames.

If you had a car involved in an accident and bent the cars frame, even if you replaced the car's A-Frames with new straight parts, it would still be out of alignment, and likely the car would pull to one side.

In this case the Spring Fork Crown (the part that holds the pivot bolt) is/was bent. Even with good straight fork legs, it will never allow the bike to track correctly.

The straight fork legs will appear bent (example, "big gap at the spring") due to the out of alignment pivot point.

Hope that helps

John
 
Crazy is exactly what I would call it. You’d expect to see a bent steer tube before the crown but stranger things right 🙃

I'm not an Engineer, just an old guy that has observed crashed Bicycles/Motorcycles/Cars for most of my life. The subject of crash testing and alignment is very interesting. It's not just the speed and weight that causes something to bend, it's also the angle of the hit.

For example, let's look at a bicycle wheel. If the hit on the rim is low (like a curb), say at 4-5 o'clock, it will result in a rim dent (flat spot). If the tire was underinflated at the time of the hit, it could also result in a tire "bead cut" as the rim pinches the tire sidewall against the object that was hit. You will find thousands of examples of this on old wheels/rims.

But let's take the same bicycle, same weight with rider, the same vehicle speed, but move the point of impact higher up to say 3 o'clock. The result will be either a bent fork, or a bent frame head. The wheel and rim will be the strongest part, and the weakest part, the frame or fork will take the damage.

It really does not take much to bend a frame, or a fork, it's all about the angle of the hit and how dense was the object you hit. Better to hit 1000 pounds of feathers, than the same 1000 pounds of cement.

Conversely, it does not take much to straighten a bent frame or fork. It's all about finding a way to securely clamp the item (without further damage), a way to apply the straightening force exactly where you need the force, and lastly how to measure and check the alignment after your efforts. The ways you straighten a bent structure have not changed much since the day of Blacksmith's.

John
 
Force of impact at 3 o'clock (running into a wall)= bent fork tube at base right above the crown. Force of impact at 5 o'clock (running over a curb with a heavy rider and a low pressure tire)= bent wheel and possibly bent spring yoke assembly. In either scenario, the forged fork crown is the most robust component in the entire fork assembly and could come out unaffected. The kind of force and angle of impact necessary to twist the cast forged crown without bending the steer tube at the base is a car running over the bicycle lying down on the ground. Now the angle the force is applied could twist the crown and destroy the fork legs, truss rods, and the spring yoke. All those damaged parts, minus the twisted fork steer tube assembly(possibly overlooked), are easily replaceable which is what I think ol' Pops did to get little Johnny back on the paper route😁 Unfortunately, after this, he had to counter weight his paper load to compensate for the pull so he could finish the years worth of paper delivery and pay pops back for the cost of repair😆
 
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