Motion Pro Shock Spanner Punch - Tool Time

A civilized tool for a crude procedure.

Motion Pro Shock Spanner Punch - Tool Time

Motion Pro Shock Spanner Punch - Tool Time

As sophisticated as modern motorcycles have become, some of them, dirtbikes in particular, have one design element that in my opinion is rather crude: the method of adjusting shock-spring preload. I’m referring to the very common type of shock that uses two large threaded rings—one that’s turned to adjust the preload and another one that serves as a “jam nut” to lock the adjuster ring in place.

When some of the components around the shock have been removed or the shock is off the bike, the rings are easy to turn with a curved spanner that hooks into notches spaced all around the rings’ circumference. But when the shock is on the bike and all the surrounding hardware still in place, the area around the rings is too crowded on most bikes to allow the spanner sufficient movement. The only alternative, aside from removing much of the obstructing hardware, is to adjust the preload with a hammer and a long pin punch. You insert the punch into one of the lock ring’s notches and whack it repeatedly with a hammer first to loosen that ring, then to turn the adjuster ring to the desired preload, and finally to jam the lock ring back against the adjuster ring.

But since this is how such adjustments often must be made, the folks at Motion Pro ([

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I only had to use this tool once to appreciate how much easier and more pleasant it made the task of adjusting preload. Being able to hold a plastic handle with your entire hand instead of grasping a small-diameter steel punch with your fingers is a much more natural act, and the tool’s length makes it easy to access even the most deeply buried adjuster rings without having your hand jammed against bodywork or frame tubes. The brass tip tends not to slip off the notches as easily as does a steel punch; and once the tip gets slightly beat-up, a quick dressing with a file or a grinding wheel returns it to like-new condition.

Yeah, it’s still a crude procedure, but this tool makes it feel a lot more civilized.