Trouble adjusting preload

I have a '07 YZ250F, I weigh 225lbs. I am trying to adjust the rear spring so that I can get the desired sag. My goal is to get it to the sweet spot the manual says (90-100mm).

The problem that I am having is that the spring adjuster will not budge one way or the other. The locknut I got loose fairly easy with a bit of pounding. I tried using the hammer and screwdriver to try and loosen it, the same way I got the locknut loose, but no luck. I decided to come here for advice in case I am doing something wrong.

I watched a video where once you got the locknut loose, to grab the spring from the rear and turn it whichever way you need to. The manual doesn't say this, and it says to make the adjustments by turning the spring adjustment. I don't have the spanner wrench (or whatever its called).

So if anyone has experience with this, please let me know and how to proceed to get my spring adjusted to the correct setting.

Thanks in advance.

Wd40 overnight, extra long punch and a hammer. Its the only way i could get it sometimes.

Excellent, thanks for the reply and great tip.

Another question I have is that, do I loosen off the spring adjuster, just as I did the locknut? After doing so, will that allow me to turn the spring to a harder suspension setting (clockwise i believe)?

This might be a silly question. But when everything is set and ready to tighten the locknut and spring adjuster. Do I just use the punch and hammer to tighten everything up?

that is correct

So I think I know what I was doing wrong, why the spring wouldn't budge. After doing some research, it seems that the bike has to be on a stand so that all the pressure is taken off the spring. Doing so will make turning the spring to adjust alot more easier.

Am I correct in making this assumption?


So after a couple hours I finally have my measurements. I added quite a bit preload and still seems that I am well out of spec for my race sag. My numbers are as follows:

Race sag: 124mm

Static sag: 19mm

To reiterate, I am a 225lb rider, not including gear, with gear I would assume 240lbs? I need a 2nd opinion if I need to upgrade to a heaver shock. What I gather is that I am at my limit of static sag at 19mm, and even if I do adjust the race sag further to reach my 90-100mm (According to the manual). It will put my static sag way out, which means I need an upgrade.

Am I correct in my theory? And that I need a heavier spring for my weight?

Here is the springs that MX-Tech recommends for my weight. One other question I have is that from the 240 to 245 is a tad heaver spring. Would it be smart to get the 245 over the 240?∏=501

Just an update. I decided to go with a Race tech shock that is 5.8KG shock as they advised from using there calculator.

STD is 5.1 I think so that sounds closer , what about the fork springs ?

I am happy with the way my forks are performing atm. I had the seals replaced and added more oil in the forks for a stiffer ride. Upon going over big jumps, my landings were plush. Perhaps I will change them in the future, for right now, I like where they are at.

Is the 5.8 from race tech to hard, or are you saying that it's good? I hope it's good, as the order is put through already :thumbsup:. I know that based on me height and weight from mxtech, the 5.1 was rounded up to 5.4, and race tech suggested 5.8.

my chart says 0.45 springs front forks and 5.6 rear so the 5.8 does sound a litlte stiff....

Hrm, not sure if I should cancel the order and get a 5.6. Will it be that big of a difference with a 5.8?

i think the 5.8 is too stiff, even a 5.5 would be better IMO

I can't find a 5.5. So I am getting a 5.6 instead. Hope this works out to be better. I had a feeling the 5.8 was to much.

What is the difference between Race Tech shocks (5.8kg recommended) and MX Tech shocks (5.6kg recommended)? I am a bit confused as there calculators both give different spring suggestions. Will the .2kg make a big difference? I'm a bit paranoid, and just want the right shock to get my correct race sag and static sag.

If someone could help me understand a bit better, that would be great. Remember, my weight with all me gear would probably be 245-250. I also ordered the Race Tech shocks @ 5.6K and cancelled the previous that was 5.8KG.

none of them agree on all bikes for all weights , it's not a perfect system but IMO the 5.6 will give good sag numbers

Excellent, thank you very much for your time and helping me out. I really appreciate it.

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