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So I think I've read every thread with the keyword FORK in it and can't find what I'm looking for

Same ol same ol, I need to stiffen the forks on my 520 EXC but ran out of money buying all the track/pit stuff and bike :thumbup:

So, I need to stiffen my front forks on the cheap

I heard you can use metal washers or a piece of PVC pipe in the bottom of the fork tubes and heavier oil to accomplish this.

So I'm asking for direction on how big of a spacer am I making?

I'm sure there are plenty of people against this, go ahead - let me have it :eek:
 

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I'm wondering the same, as I would like stiffer suspension on the front of my ancient little XT250, and there's no way I'm spending money on the suspension of a bike as old as mine, I just prefer stiffer suspension over soft
 

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im wondering the same with my 02 crf450r.. wanna lower the front by trimming the spring and then add thicker oil.. need some know how info first though..
 

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You need to shorten the spring to make it stiffer, then make longer PVC spacers to maintain the spring preload (amount spring is compressed with bike on stand), usually 10mm to 13mm. Adding more preload with longer spacers or washers will NOT stiffen the spring rate, only keep it higher in the travel, and usually, harder to turn. How much you shorten the spring is something you will have to research, maybe Race Tech ??? Good Luck, WD
 

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im wondering the same with my 02 crf450r.. wanna lower the front by trimming the spring and then add thicker oil.. need some know how info first though..
To shorten travel you will need to go deep into the guts of the cartridge assy machining and adding spacers.....not just shorten the springs.
 

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Exactly...........and if not properly tempered they spring will break.

You need to shorten the spring to make it stiffer, then make longer PVC spacers to maintain the spring preload (amount spring is compressed with bike on stand), usually 10mm to 13mm. Adding more preload with longer spacers or washers will NOT stiffen the spring rate, only keep it higher in the travel, and usually, harder to turn. How much you shorten the spring is something you will have to research, maybe Race Tech ??? Good Luck, WD
 

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what about to cut say,, 4 inches from the spring,, then just add that 4 inches back with the pvc spacer to keep that extra play from opening up.. sounds simple. and you keep he same spring rate... (same tention):)
 

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To shorten travel you will need to go deep into the guts of the cartridge assy machining and adding spacers.....not just shorten the springs.
Shortening the forks and shock is easy, you can use a space in the shock and add a couple of topout springs in the forks to the cartridge fork. you can just do that by itself as you will be adding the same internal preload as you shorten ie. if you shorten the forks by 1" you just added 1" of internal preload causing the forks to ride too high in the stroke as mentioned above.

Shorter fork springs and a topout spring with SX style valving works well
 

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True but the drilling and cutting required to disassemble the cartridge assy can easily be way over the typical back yard mechanics capabilities.

Shortening the forks and shock is easy, you can use a space in the shock and add a couple of topout springs in the forks to the cartridge fork. you can just do that by itself as you will be adding the same internal preload as you shorten ie. if you shorten the forks by 1" you just added 1" of internal preload causing the forks to ride too high in the stroke as mentioned above.

Shorter fork springs and a topout spring with SX style valving works well
 

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what about to cut say,, 4 inches from the spring,, then just add that 4 inches back with the pvc spacer to keep that extra play from opening up.. sounds simple. and you keep he same spring rate... (same tention):)
If you cut that much out the spring will be a ton heavier. Removing coils is what makes it stiffer. Each coil absorbs an equal amount of the movement...less coils have to absorb more making it stiffer.
 

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If you cut that much out the spring will be a ton heavier.




what are you talking about?? make it heavier? like make the spring stiffer?.. I understand what you are saying but cutting the spring down some is not going to make it (physically) heavier..
 

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you shouldnt need to go anywhere near a drill or cutter with the twin chamber forks to pull the cart apart, but yeah I know what you mean
 
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