Rear Spring Sag Only 3" which way to turn collar?

2005 WR450F

I just changed the springs front and rear (RaceTech). here is what I have.

Type of Riding: Desert / Enduro / Trail

Rider Weight: 215 lbs

Recommended Spring Rate: 5.64 kg/mm (use closest available)

Stock Shock Spring Rate (measured): 5.3 kg/mm (stock)

Available SRSP 6228 Series Springs are:

SRSP 622856 RT SHK SPR 63.4x60.6x270 5.6kg

The spring I installed in the rear is a 622856 (stamped on it) which is perfect for my weight according to RaceTech

I installed the shock with the collar screwed to about where the stock spring was. I measured race sag and came up with 3 1/8 inches - I am striving for 4 1/8 inches, which is about 105mm sag. I unscrewed (raised) the collar which made the spring slightly longer, well my race sag is STILL 3 1/8" . How is this possible?? What am I missing?? I did the sag test with me on the pegs, sitting on the seat and even sitting back farther to no avail.... Any thoughts? :cool:

Back it off in stages until there is very little preload. If that does not do it then you have too heavy of a spring. It is also important that you are fully geared up and full of fuel. Have you ridden the bike at all? If not, you need to ride it so the spring will take a set. Also, does the bike have any sag when you take it off the stand and set it on it's own weight. It should have about 3/4" and if it does not that is also an indicator of too much preload.

Ok, not sure how you're measuring your race sag but since the above post by maxtherat addresses the static sag.

You have to set static sag first, then race sag, race sag is a cumulation of static sag + sag of rider on bike so if you're at 3-1/8" did you add the static sag or not - you might be closer than you think.

It might be as simple as you didn't turn the collar counterclockwise enough.

To increase race sag, the spring has to decompress, so the rings have to be turned up allowing the spring to lengthen.


2005 WR450F

I.... Any thoughts? :cool:

i just put in the exact spring on my bike. as you know it needs to go counterclockwise or up the r spring thus lowering the seat. mine ended up at 3.5" but i just called it good.

im at 220.

Sorry it been awhile. I turned the collar up (counterclockwise) about 3/4 of an inch total in increments. Race sag did not change as I loosened it in increments between rides. I was fully geared and fueled. I have not checked static sag, I will do so this weekend. So, am I supposed to add the static sag to the race sag??? Thanks for the info!

Yes that's correct. First measure from two common points with the bike on a stand. Ex. top of axle bolt to edge of fender. Next take bike off the stand and remeasure from the same points. This should be around 3/4" lower or so. Next get on bike, feet on pegs, and have someone measure the same points again. So if the last measurment is 3 1/8" lower then you are at 3 7/8" and that's close enough. Just subtract your last measurment from the first and that is you total "race" sag.The spring will sag some after you ride it so you may need to increase preload. This is the key point: if you get your 4" of race sag, but then the bike does not sag at all under it's own weight then you have too light of a spring and you need to much preload to get the proper race sag. On the flip side: if you get proper race sag set and the bike sags over 1" or so under it's own weight then you have too heavy of a spring and you are not using enough pre load to get the proper sag. Sorry for the overly lengthly response. Hope it helps

Thanks Max, good explanation. I measured my static sag and it was about 2"!!! All because I was lengthening the spring, trying to get it to 4". I wasnt aware I needed to measure static sag and add it. Cool! Going to the dunes this weekend, so I will set it for 3/4" and eat a big dinner lol! Thanks everybody! -Dave

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