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How to Set Spring Preload


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Preload on the rear spring is usually set indirectly, that is, by adjusting preload for a race sag of about 1/3 of the bike's total rear wheel travel, which is about 4 inches on most bikes. Some experts, however, recommend setting the preload directly on the spring, and advise a preload of 6mm, which, according to them, will give you about 4 inches of race sag. I'm not sure why this would be an advantage over the standard way, but I worked out a procedure for setting preload this way, and it did indeed result in a race sag of 4 inches on my TE-250...

- Put your bike on a stand

- Loosen both nut-rings on your rear spring

- Backoff the lock ring an inch or so

- Backoff the main ring until the spring relaxes to its full length

- The lower edge of the main ring should just barely touch the spring

- Get a small hose or piece of tubing 6 inches long

- Spray paint thru the tubing on the threads of the shock body

- Mark a pop-sickle stick with 1 or 2mm marks (your choice)

- Rotate the main ring clockwise (CW) to compress the spring (add preload)

- Stop every full rotation and check the preload with the popsickle stick

- Continue adding preload until you have moved the spring about 6mm


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