Unequal Pitch Shock Springs

2 replies to this topic
  • gerald28

Posted November 11, 2007 - 08:22 PM



The stock spring on my 06 YZ450 is the equal pitch spring. But they offer an unequal pitch spring that is softer at the beginning of the stroke and hardder at the end. I believe this is also called a variable rate spring.

My first reaction is this sounds like a good idea. Are these springs popular/better? Is it better for enduro riding than MX since it soft at the beginning?

San Antonio, TX

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • grayracer513

Posted November 11, 2007 - 09:20 PM


These springs work much differently in practice than a straight rate does, and they aren't for everyone

Imagine, in place of your single rate 10" spring, you have a spring with an 7" stiff section and a 3" soft section at one end. The stiff section is 100 inch pounds, and the soft section is 50. Many believe that the soft section will completely compress before the stiff section moves, but that's not correct. If you apply 100 pounds to the spring, the 50 pound section will compress 2 inches, true. But it sits on the 100 pound section, doesn't it? That means that the 100 pound section will compress an inch, too. That means that the effective rate of the spring is 33 inch pounds until the 50 pound section binds up, at which point it becomes a 100 pound spring. In dual rate springs like the example, this rate spike is sudden. In a progressively wound, or "unequal" rate spring, the spring rate ramps up more progressively as the tighter wound coils bind against each other.

As it is already, the linkage produces this effect with a straight rate spring, because the shock travels farther per inch of wheel axle travel in the last inch than in the first, so having the spring do it as well may not be what you're looking for.

Most people don't use them, but they do serve a purpose.

  • gerald28

Posted November 11, 2007 - 10:28 PM


Thanks for the great reply!

Related Content


BIGBORE FOR YZ450F 2006? by Taattie94

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 5 replies

Is it worth it? (Cam and High compression piston) by macgi77

Dirt Bike   Make / Model Specific   Honda   CRF 150/230 F/L
  • Hot  36 replies
WR Camshaft Swap Info - last post by jamesm113

WR Camshaft Swap Info

  • 0 replies

Wilson the Blue Privateer by jetfuel

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  50 replies

James Stewart back on a YZ450F by YamaLink

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.