KTM Shock Springrates

In this column, number 13, I am going to address proper shock spring rates for KTM’S with PDS shock systems.  In my column # 5  I detailed how springs work, how they are rated, and how to measure race sag and static sag. (You can access my back columns at www.brucessuspension.com.)

As a quick review: the 1998 to 2002  KTM’s  should be set up with 97 to 105 mm race sag and 30 to 35mm static sag.  The 2003 and 2004 KTM’s  should be set up with 115 to 120 mm race sag and 40 to 45 mm static sag.  The 2005 and 2006 KTM’s  should be set up with 110 to 115 mm race sag and 35 to 40 mm static sag. 

The following chart shows recommended spring weights based on rider weight (as wearing casual attire, not race gear.) 

*** This chart is NOT for 2008, or 2007 SX  Models, and should only be used for 2007 non SX bikes, and older. ***

These rates provide a good starting point for most riders.  Some riders may want to deviate from these suggested rates to accommodate individual rider styles or terrain. If you race or ride mostly in sand, you probably should go to the next stiffer spring (i.e. from an 8.4 to 8.6).  Conversely, if you ride a lot of rocks, you may prefer the next step softer (i.e. from an 8.4 to 8.2).  “Out of the crate” KTM’s had very poor stock spring rates:  the 1999 to 2003 models were fitted with a 7.1 to 9.0 progressive spring, which did not work well for ANYONE.  The 2004 models got a little closer to being correct with an 8.8 spring, which was good for a 200 pound rider on a 2 stroke and a 180 pound rider on a 4 stroke.  The 2005 and 2006 models were fitted with a 7.6 spring on the 2 stroke which was good for a 140 pound rider.

If you fit the rear shock with the spring of proper weight, you will feel a big improvement in performance of the back end of your KTM.

Until next time, here’s to smooth riding. 

SHOK DOC (Bruce Triplett)