Introduction and spring rate question

6 replies to this topic
  • tdamore

Posted September 10, 2008 - 12:45 PM


Hi all, I just picked up a 2003 yz450f after being off the dirt for about a year after the birth of our first child. I have a question about spring rates and I am hoping someone can point me in the right direction.

My understanding is that the stock spring rates for the 03' are as follows:

.46kg/mm for the fork
52.0 N/mm for the rear shock

Approximately what weight rider are these ideal for? I am about 210-215 with gear and am assuming that these rates are probably for someone closer to 165-175.

Thanks in advance!

  • grayracer513

Posted September 10, 2008 - 01:12 PM


The stock rates are .46 and 5.3, and the bike was built for riders in the range of 180-200 (wearing gear). For your weight, you're better off at about .48/5.5

  • tdamore

Posted September 10, 2008 - 01:29 PM


Great, thanks! :thumbsup:

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  • grayracer513

Posted September 10, 2008 - 01:49 PM


You're welcome. Now, do something about that avatar. :thumbsup:


  • tdamore

Posted September 10, 2008 - 02:45 PM


You're welcome. Now, do something about that avatar. :thumbsup:


LOL - I forgot about that. I was on a 450x and then a 650r before the little one came.... I started on a 1980 yz80 waaaaay back when if that helps :-)

  • brianmx

Posted September 14, 2008 - 07:11 PM


what spring rate would work well for a rider that weighs 170lbs. I ride motocross beginner. thanks for info

  • grayracer513

Posted September 14, 2008 - 08:13 PM


If that's your weight in your street clothes, the stock springs are OK.

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