Backwards shock??

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Nov 12, 2023
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I've been searching useing every possible combination of words I can think of with no luck.
I'm in the middle of a build and I want a shock that works when it is pulled apart not compressed. I know it's a thing because harley uses them on there softtail models as well as Buell. If it comes down to it I can make something I'm just not sure how to incorporate the dampening and such. Unless I just build a "cage" type thing around an existing shock.
So I guess I'm asking if anyone knows of a manufactured shock like this. Or am I going back to the drawing board?
 
First off, damping is controlled by fluid flow so in theory any shock with adjustable compression and rebound should be able to work backwards.
Second, don't the examples you mention all use compression springs ?
A compression spring on the outside of the shock body ?
Are there any examples of suspension design that use extension springs ?
Creative linkage designs make them work.

( There are a few examples of elastic cords used as suspension springs with no damping incuded )
 
It's kinda hard to get a good picture but these are under a harley softtail. I cannot tell if it is a compression or extension spring and that doesn't really concern me as much as the way the shock does its work by extending and not compressing
 

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Doing a quick 2023 Harley Softail parts page lookup shows a typical compression spring/shock setup.
Maybe a different year/model ?
 
I have no knowledge of a Pull Shock Absorber being used in bicycles. Pull-Rod shocks are not uncommon in F1 racing. It's a very different valve action than our usual Push shocks, the opposite actually.Image 5-25-24 at 1.02 AM.jpeg
 
If the shock does not support vehicle weight, then you might try a recumbent trike steering stabilizer. Also available for motorcycles.

 
I've been searching useing every possible combination of words I can think of with no luck.
I'm in the middle of a build and I want a shock that works when it is pulled apart not compressed. I know it's a thing because harley uses them on there softtail models as well as Buell. If it comes down to it I can make something I'm just not sure how to incorporate the dampening and such. Unless I just build a "cage" type thing around an existing shock.
So I guess I'm asking if anyone knows of a manufactured shock like this. Or am I going back to the drawing board?
Hi.

Search for "pull shock". They were most recently used on some Cannondale and Scott mountain bikes.


Avner.
 
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Do we assume when you say "shock" you mean dampener? 99% of air spring and coil spring 'shocks' only extend (push). If you are planning to use a separate spring, I believe most shock absorbers are 50/50 compression/extension and would function well as dampeners and are valved for the approximate weight of a bicycle + rider. You could use an air sprung shock with the air let out or remove the coil from a standard MTB shock. Either type are available on Aliexpress for about $100 new/shipped.
 
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In most cases, suspension dampeners have more extension (rebound) damping than compression damping because suspension compression is resisted by both the damper and the spring while suspension extension is resisted only by the damper.

Avner.
 
Hi.

Search for "pull shock". They were most recently used on some Cannondale and Scott mountain bikes.


Avner.
Yes this is what I'm talking about. Thank you for the correct term. As per the norm I may have made a design change mid build, I came across some airbags, already have a small maybe one liter air tank and a few small compressors laying around. This may be a horrible idea. But I think it would be pretty awesome to have an ebike/motorcycle be able to just drop down to the frame when parked. I got the rough layout of my batteries done.
 

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