.43kg to .45kg difference

I was just wondering just how much difference this fork spring change would make. I'm 205lbs (235-240 w gear), and ride a '06 WR250F on trails. The stock fork /shock springs are .43 and 5.1. The race-tech and mx-tech calculators both recommend a fork rate of .45 (which is between the available rates of .44 and .46), and a shock rate of 5.1 (same as stock). I was a bit surprised at the recs, since 35lbs of gear is a big weight difference. Last time I checked my sag settings, they were within range towards the soft side. My plan is to run the fork until it needs seals ect. then maybe throw in one or two shims to make up for the slightly soft springs and any set that occurs. Not sure how much difference there would be between one or two 2.3mm shims under the stock springs. Opinions/advice appreciated.

I typically have to go the opposite way (I weigh 135 w/o gear) when I re-spring a new bike. The last bike I purchased just about two months ago came stock with .45kg./mm fork springs and a 5.1kg./mm shock spring. I went with .42kg./mm fork springs and a 4.7kg./mm shock spring and could feel quite a bit of difference right away. I also kept lowering the stock 360ml. oil volume in the forks by 10ml. every ride until I reached a point that I could bottom the forks. You can increase the bottoming resistance of the last 4” of you fork travel by adding oil through the air bleed screw hole. Make sure you know how much oil volume you are starting with and also take note of the maximum oil volume your manual says you can run. The only problem that I have experienced by adding oil is that you will reach a point where you may start to feel some mid-stroke harshness. As far as the rate of .45 coming in between the available rates of .44 or .46, I would purchase the .46kg./mm. I’m know that everyone has their own personal preference on how their fork feel. I tend to like a little stiffer spring rate to help hold the front of the bike a little higher on the initial stroke. Again, that’s just my preference.

Hope this helps.

The .46 sounds like the ticket. Anyoneone know what fork springs will interchange with the '06 WR? What's a good source for takeoffs? Can the springs be changed easily with the forks on the bike?

The .46 sounds like the ticket. Anyoneone know what fork springs will interchange with the '06 WR? What's a good source for takeoffs? Can the springs be changed easily with the forks on the bike?
put .46 in one leg and a .44 in the other, that will give you a .45!

What was you free sag? After you set your rider sag,That will tell you what you need. Race-tech or one of the other suspension shops has a real good guide on setting the sag. It surprised me that on both my bike 250f and 426f I needed to go with lighter springs. AT 200 in gear.

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