KTM WP Shock Spring PDS 125 200 250 450 530 SX EXC SX-F

Original KTM WP progressive PDS shock spring.

PDS-2 = 75 - 97 / 250

Most of the modern KTM WP PDS systems are set-up with straight rate springs. A lot of riders and tuners prefer to fit older progressive springs to give the KTM a more Japanese feel. This is a great change if your previous bike was a Yamaha or Honda and are struggling to accept the feel of the KTM WP PDS shock.

This progressive spring is very well suited to riders who weigh more than the recommended 75 - 80kgs. It is also a cheap way to adjust the seat height of your Orange Mongrel by having more than the recommended race sag, for those who are vertically challenged but want to resist shock bottoming.

If you want to know if this spring is suitable for you let me know your weight in riding gear, the bike model and year.

I recently fitted a PDS-6 spring to my friend’s 250EXC-f. This guy is one of those people who doesn’t believe in changing the factory component to suit his needs. He is 90 kg and on the short side. He ran more than the recommended race sag using the standard spring (69 - 250) as he like the confidence of being able to get both feet to touch the ground on the trail. This previous set-up lead to extensive bottoming. With the PDS-6 spring now fitted we were able to maintain almost the same seat height but with an improvement in bottom resistance. This wasn’t the only thing he noticed. His rear tyre was two rides old but he immediately felt like it was new again as the rear wheel was better planted on the ground providing more traction. He also noticed the firmer shock spring allowed him to loft the front wheel up over obstacle with less effort. All in all, he regretted not listening to me earlier and although he was very happy with the suspension of the bike before the changes he can’t believe the positive improvement something so simple to do, has made. He is now very, very happy. Next on his list are the forks.

The springs are listed going firmer down the page. The WP PDS numbering system is a bit weird as KTM originally only had 5 PDS springs getting firmer from PDS-0 to PDS-4. The factory teams wanted intermediate progressive springs between these so WP added an additional 4 springs to the selection getting firmer from PDS-5 to PDS-8. The total collection (getting firmer down the page) is listed below for your reference:

PDS-0 = 65 - 83

PDS-5 = 66 - 86

PDS-1 = 70 - 90

PDS-6 = 71 - 91
PDS-2 = 75 - 97

PDS-7 = 76 - 95
PDS-3 = 80 - 103

PDS-8 = 81 - 99
PDS-4 = 85 - 111

The PDS number system confused some suspension tuners so later WP removed the reference to PDS altogether and only included the rates (e.g. 75 - 97 / 250). The number following the / is the spring length.

The above reference provides you with a tuning guide to determine if the spring I have might be suitable for you. Your current spring should have a number on it. You may just need to turn the spring around. Most savvy tuners will ensure this area of the spring isn’t rubbing on the airbox. If you can’t find it I would assume it is stock, then check the parts manual (or internet) to determine it’s rate. As a rough guide your bike should have 25 – 35mm of static sag and 105 – 115mm of static sag. Many articles on the web will help you find out how to measure these values if they mean nothing to you.

If your spring has just one number followed by the length (e.g. 69 / 250) this means it is a straight rate spring. This spring is softer than the PDS-5. From 2000 onwards the springs on the WP PDS shock have generally been getting softer. This is not to say the bikes have been getting softer. This is because WP has continued to develop the internals of the shock to be more progressive. They also have higher gas pressure. This has enabled KTM to reposition the shock in the frame altering the ratio, to improve performance.