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New fork springs different length.

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I got some heavier springs from racetech, and put them in my forks today along with new fork seals and bushings. 

 

The new springs I got from match the 17.9" length in the manual, the old ones I pulled out were about 18.5"

 

The manual says the minimum length is 17.7", but does not address anything on the long side. 

 

Is this an issue? I did not take apart the upper fork to the base valve and all that, will I need to go in there and change out spacers/washers for the different length springs? 

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Since you didn't mention the bike, I'll assume it's a yz250. The springs you got from RT(454mm) are correct for an '06+ yz250 and what you pulled out(470mm) are from a '10-'13 yz450. Would assume someone prior to you put in the wrong springs which means you were running an extra 16 mm of preload

 

I guess it's possible that the spring seat was cut 16mm to compensate, but I'm not 100% sure you can take that much off. (edit: you can't take that much off a stock spring seat)

Edited by homo erectus

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My mistake, I forgot to name the bike. This is on an 09 yz450.

 

The '09 450 also uses the 454mm spring like the 2-strokes so somebody must have put a set of the '10-'13 springs in it at some point.

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i have 11 450f spring on my 2006 yz250 is that problem ?

doenst work right?

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i have 11 450f spring on my 2006 yz250 is that problem ?

doenst work right?

 

No problem they should fit 

according to the KYB catalog the following Yamaha bikes

all share the same fork spring part numbers and are fully interchangeable :

 

2006-2015 YZ125

2006-2015 YZ250   (2T)

2006-2013 YZ250F (4T)

2006-2009 YZ450F

2012-2015 WR450F

also a few 2010-13 Husqvarna bikes as well

 

so no the 2011 YZ450F springs would not be compatible with the YZ250, see following posts

Edited by mlatour

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No problem they should fit, according to the KYB catalog the following Yamaha bikes

all share the same fork spring part numbers and are fully interchangeable :

 

2006-2015 YZ125

2006-2015 YZ250   (2T)

2006-2013 YZ250F (4T)

2006-2009 YZ450F

2012-2015 WR450F

also a few 2010-13 Husqvarna bikes as well

 

*also pending the donor 450 had the stock springs or aftermarket ones of the proper length: 454mm

 

This is not correct.

 

As stated in my original post to the OP, the 2010-2013 yz450 fork springs are 470mm. As your posted information states, the '06-'9 yz450 have 454mm springs, but jannef stated that he has 2011 yz450 springs in his 2006 yz250 so they are 16mm too long.

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Thanks for picking up on that homo erectus, I got the OP's '09 and jannef's '11 infos mixed up !

 

I'll edit my post ASAP.

 

So to jannef, indeed as homo erectus pointed out above, the 2011 450F springs are too long for your application.

Edited by mlatour

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This is not correct.

 

As stated in my original post to the OP, the 2010-2013 yz450 fork springs are 470mm. As your posted information states, the '06-'9 yz450 have 454mm springs, but jannef stated that he has 2011 yz450 springs in his 2006 yz250 so they are 16mm too long.

hmmm weird the spring was shorter in my 450 than my 250 :)

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As mentioned, just make sure they have the proper preload (4mm is great).  You may need to add spacers or something.  It could also be the springs you had in there had a bunch of un-necessary preload on them

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