It's actually quite simple: Sprindex springs have a spacer in the lower part that can be moved to 15 positions. This allows you to influence the active positions of the spring and thus adjust the spring stiffness. For example, the Sprindex spring can be set to a soft setting for trail riding - and if you're heading to the bike park, the spring can be set to bigger, harder hits in no time at all, preventing the rear triangle from bottoming out. The adjustment range is also practical if your body weight has changed or if you are traveling with a lot of luggage. Sprindex springs are available in three different lengths and four spring rates.

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