Help me pick some springs

2008 YZ450

I weight 190-195 lbs w/o gear.

Riding type is Off-road/desert, Novice

Front travel from manual: 300

Front extended: 613

Front static: 581

Front rider: 527

Measured from top caliper bolt to lower triple clamp bolt.

Rear travel from manual: 310

Rear extended: 625.5

Rear static: 590.5

Rear rider: 514.5

To me the rear feels fine and the numbers are really close. I never really like the front. It seems like it's always too stiff in rocks or too uncontrolled in whoops. I can adjust clickers and be satisfied with one or the other, but not both. Since it needs fork seals (again) I want to at least get the front sprung correctly. RaceTech calculator recommends .487 to .505 depending on my 5lb weight fluctuation or adding a larger tank. I don't think my IMS3.1 is really adding that much, but I know it's there. Stock springs are supposed to be .47.

So, do I go for a 2% increase to .48 or a 6% increase to .50?

Racetech calculator is usually wrong in most cases.

Rear you want 105-6mm rider sag, 34mm static sag (+-2-3mm).

Your 35mm static is good .

111mm rider sag is a bit muich. Tighten your static sag to about 31mm and recheck your rider sag.

On the front your 86mm rider sag is a bit much. You want about 75mm .

Static sag is only 32mm. Not nearly enough. You need stiffer fork spring. Less preload. What is your current fork spring rate ?

I am heading out to double check the front static/preload as that number doesn't seem correct.

Springs are stock. .47 I believe.

Double checked static number and it was 571.5. So that is right at 14% like you say it should be.

I'm also getting between 527 and 533 for rider sag up front so I'm thinking only jump to .48. It seems like such a small difference, but maybe worth it.

Be sure to adjust your rear sag before changing fork springs. It will make a difference.

I would have thought you need lighter than .47. I ran .42 kg on my 525EXC KTM. .44 was too stiff and the bike wouldn't turn although it worked good on whoops. I weigh 180-185lbs. I am currently running .40kg on my WR150 Husqvarna. Stock was .42kg.

If close you might try a tad more preload on the fork spring and see how that affects your sags.

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