This cant be right...

Today I decided to tackle the suspension, specifically the rear sag on my DR-Z400S that I've had for about a year. Prior to today, the only thing I've ever done with the suspension is "click hard, click soft... neat". After reading how to set the sag, it seemed easy enough and everyone always says the suspension makes the biggest improvement in a bike. Long story short, I had my rear shock loosened all the way up, and I only had about 50mm race sag, but I had 100mm static sag at that point. From what I read, that would indicate a spring that is way too hard for me. I am 99% certain that it is the factory rear spring, which is best suited for a 185lb rider. I am 175-180lbs. Unless I am doing something extrordinarly wrong, this makes no sense to me. I'll list the steps I performed and please let me know if I made a wrong turn.

1. Reset all adjusters to factory settings (eg: 11 clicks out)

2. Set static sag to 25mm as measured from the center of the rear axle to a point above it on the fender.

3. Measure laden/race sag. (fender to axle distance, empty bike held for balance) - (fender to axle distance with me in gear standing on pegs while roomate measures distance)

4 Adjust rear shock preload to compensate for lack or excessive race sag.

Before I started messing with the shock, it was all the way down, full preload. I continued to release preload until I was all the way out. At that point, I had 100mm of static, but only 50 mm race sag. The bike was at one point lowered, but has been upright since I have owned it. THe rear spring is yellow if that helps in any way.

I don't think the suspension has ever been serviced either, but this seems (to me) to be a spring issue. So the service part would be somewhat irrelevant.

You're going about the measurements backwards.

1. Place the bike on a stand so that the rear wheel is off the ground

2. Take a measure ment between two points, such as: A. Center of rear axle, to B. Seat or rear fender bolt - whichever is easily accessible and close to vertical from the rear axle. Record this measurement

3. Take the bike off the stand. Sit (or stand) on the footpegs while someone holds the bike to help you balance and have another person measure from the same points as in step 2. Subtract this measurement from the one you obtained in step 2. This is your "rider sag"

4. Get off the bike and with it's wheels still on the ground, measure from A to B again. Subtract this number from the number obtained in step 2. This is your "free sag".

5. Compare the results to the recommendations in your owners manual. This will tell you if the standard springs are correct for your weight or not.

Got it?

Sweet, fixed! Thank you much.


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