I am about 215 lbs.. the guy I bought the bike off of was shorter and maybe weighted about 170 if that. He was the 2nd person to own the bike and said the guy before him custom adjusted the shock but he did not know what was done. I think he put a light weight spring in. I dont have a real reason for thinking that other then nothing really looks custom for the rear shock. and the spring does not look like it is cut or anything. I was thinking of buying a little heavier duty spring to replace the one that is there..
I was wondering what thoughts you guys might have on that and possibly any ideas about which one would be the right one for my weight?

 

If you ride off road, I would be looking at respringing the fork too. Stock klx's are under sprung. I'm below your wt class and up'd the front spring and living with the stock shock spring.

 

The front seems to be ok.. The trails I was on where very rocky and rooted wood riding. The front handled fine but, the rear was eh.. I was reading and found this :
Or maybe the shock is fine and just need to get a more heavy duty spring. If I were to go with a heavy duty sprint which one?

Also, read a few other items that the shock should have 150psi in the tub next to the shock? I am knew to shock mods.. eng mods np, shock mods meh. I am assuming you can just attach a pressure measuring tool like one for your tire?

For a spring I was thinking something like this

 

I did the race tech springs and gold valve kits, directly through them.
They have a spring rate calculator on their web site.

Check the FAQs (link in my sig line) for more on suspension. It's fairly easy to check your rear spring sag settings to find out if you need a different spring.

Bruce's is good: kb1

 

Thanks great FAQ. I read through it and a lot of GREAT info. After reading the shock part, I think my sprint needs to be upgraded to the pleasantly plumb guy spring.

Here is a pic with me just sitting on it keep in mind I have a lot of layers on because it was like 28 degrees. You can how the back fender almost looks like it is just above the tire. I didn't bottom out at all

 

Cogent Dynamics is a great place for suspension upgrades
They can recommend springs and valving based on your weight and riding style
https://www.motocd.com/

There's lot's of KLX information in the web site I maintain
KLX250S Home Page

 

Cogent is an excellent suggestion.
At 225 lbs., I bought a Racetech spring based on their calculator. It works very well.
From your photo, it appears that something is wrong. Perhaps your sag is set incorrectly through the preload ring on the spring. I would also suggest having a shop check the nitrogen charge. The volume is too small to check it yourself as you will lose a good amount of pressure just checking.

 

Thanks. I agree something deff feels off with it. I was checking out the spring cal and looks like I need a 7 kg for a spring. I might wait to grab it until I reset the shock this week end.
@fzrcraig I'll start with setting bottom and top clicker to factory default and then moving it from there. Since we are around the same weight, what did you setup yours to?

Hopefully I will be able to bring the bike to a shop as well and have them check the nitrogen, maybe a seal in the shock is bad and nothing left in it.

 

When I installed the spring, I set both adjustments to the middle of their range. Since that time, I have backed off the compression two or three clicks and it seems to work well.
In terms of quality, the shock itself isn't too bad. It's just a matter of setting it up properly. Can you take a close-up photo of the shock, ideally with you on the bike?

 

@fzrcraig Sure can. I will try to take the pic tonight. If not then definitely tomorrow morning'ish.