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Lowering forks internally on a CR85?

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I have a 2004 CR85 that I'm looking to lower internally for road racing. I'm looking to lower them 3" (best measurement I could find through Internet surfing). Here is a link to the schematics. I need to do this myself, cant afford to send them off.

CR85fork.png

I'm thinking a spacer needs to go on #22 and the spring needs to be cut an equal amount, keeping spring rate in mind?

As of right now it has 20wt oil and a BBR heavy spring .44kg. So I imagine 3" would raise the rate a considerable amount. I'm using way to much travel now under heavy breaking so stiffer may not be so bad. I will need to also revalve so I can use thinner oil for better fork feel. I don't have the forks apart now, just getting everything in mind before I do.

Any and all help is highly encouraged. I cant find any threads on how to lower these forks, although I know it has been done more then once.

Thanks

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that sounds about right

if you can grasp what to do from looking at the diagram it should be no problem for you once its apart.

the spring rate is in proportion to the number of active coils so you will be able to work out the new rate before you cut them

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I'm using way to much travel now under heavy breaking so stiffer may not be so bad.

:busted:

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So my question is about spring rate. The springs in there now are .44 if i put a spacer in reducing the travel by 3" and compress the spring the 3" according to what I have read, the spring rate would be the same. My problem is I don't think my sag would be the same after compressing the spring that much.

So, I would need a different spring cut down to get the right spring rate and sag. Does anyone have the information I would need to determine the right spring to cut down? I would need the amount of active coils, outer diameter, wire thickness and total length of a stock CR85 spring, and or the stiffer optional spring to figure this out.

Please if I'm way off here please let me know.

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IMO shorter travel needs stiffer springs. so I would cut the springs 3".

if you want to know the new spring rate, tell us the length and active coils of your current spring...

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10% shorter active coils is 10% stiffer

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10% shorter active coils is 10% stiffer

This is what I'm going by, I'm just not sure if my BBR's are the same length as the stock and other springs available for the CR.

Ill pull mine and get a base line of what I have now and what they will be 3" shorter.

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