Greetings to all klx!
Long ago I follow with interest all the issues discussed here, and I decided to contribute a few details on the suspension of the klx250 2009.
For 2009 we have clarified previous models that SAG is the same as the rest of the bikes off.road. But the 2009 is significantly shortened length of suspensions: 255mm front and 230mm rear.
This significantly alters the action of SAG that would become:
FRONT: 22/25% of 255mm = 56 (+ cross) / 63mm (+ Enduro). Free Play: 10/15mm.
REAR: 230mm 30/33% = 75 (+ cross) / (+ Enduro) 80mm.

We all know that the fork spring of 2009 are very soft klx250 (0'38kg / mm OEM) as his replacement is strongly recommended to meet the specifications of the SAG. I recommend contacting MOTO-PRO, which has a good service and options for our bike. From here I want again to thank John for his dedication and customer service as quickly and efficiently. For my weight these are the springs for a 80kg rider. (0'42kg / mm).



The improvement of the bike has been very good, it feels more stable and rigid, being more stable on sandy, muddy, and at high speed. Unfortunately I could not install the Valve Ultramax MOTO-PRO (below), yet the improvement has been dramatic. Circle usually very rocky terrain where it is necessary that the fork work quickly and stiffly. I was afraid that with the new springs harder to lose sensitivity and absorption capacity against these minor obstacles, but I set the compressor regulator to stop the soft fork (21clicks out) and have left the oil KAYABA 01 OEM (SAE4 '1 approx) with excellent results. I have never had problems with a strong rebound, the bike exceeds trialeras perfectly.
http://www.youtube.com/watch?v=MQp6VObRrU4

In the rear shock spring series is somewhat harder than the fork (5'5kg / mm OEM OEM preload 107'5mm) MOTO-PRO recommending a spring 5'6kg / mm for the 80kg. However, for those who weigh about 75-80kg rider weight can preload the spring to near the limit specified by the manufacturer (limit preload 123mm) and approach the ideal of SAG specified. Not the ideal (a law says that the suspension unless a spring preloaded best work) but can serve as a relief to ameliorate excessively soft cushioning.
For those who exceed 80kg in weight and not willing or able to put a spring 5'6kg / mm there is another little trick for improvement: links to klx2007: 117mm measured against the model 119'5mm 2009. In addition to increasing the height of the seat also has a second effect: the strength of shorter link lever is lower, so the OEM spring is harder and can save the situation. Links + short = more duerza spring. It is a simple law of the lever.

Finally I would like to state regulation in the shock compression and rebound once regulated SAG I personally works well.
Compression: 17 clicks OUT
Rebound: 12 clicks OUT
If our usual spot races are easy trails with great speed and little stone we can tighten the compression and rebound clicks.

 

Sharp hits on the front are way too abrupt with the stock valving. You'll really think you hit nirvana when you replace the crude system they have on there now....

I just went back and watched your video. Wow. Your helmet must be very loose, or, your front end is so bad, it's jarring the bejeezus out of you....which is exactly what the stock front valving provides: very poor hard hit absorption. It's just way too slow to react. You'll see why when you take it out to replace it.

 

Loose helmet and/or loose camera mounting for sure! Or rubber-neck. LOL

 

Not the neck that moves, not the bike, is the camera! jajaja
It is a very archaic system of fixation with a camera so cheap!







While it is true that the course had many stones that are not reflected in the video. See if the XR400 and CRF450 sometimes snag the slope and obstacles.
Here in an easier way.
http://www.youtube.com/watch?v=9QprO5UDTm4

 

jeff, John at Moto Pro where you got the springs, can tell you how bad the main fork damper piston is in not flowing enough oil to allow the shim stack to fully function and prevent harsh compression spikes. Regardless, the front springs and damper units are the major weak link in this bike for off road performance. The rear shock ain't so hot in stock form either, but the front is horrid. I used a Race Tech complete valve kit for my KLX fork, but I would speculate that John's Moto Pro valve kit probably works just as well.

 

Yes, I also read that the MOTO-PRO kit works best. Sure gives greater compression and rebound tenderness in the fork. The stock valve of the bike is too simple for you to perform well.
For the same reason I recommend to anyone without modification of the valves and install springs harder to regulate compression clicks towards softer.

 

I talked to John on Friday and he didn't say anything about it needing valving. I bought front and rear springs from him. He told me all it really needs is to be sprung properly.

 

You wouldn't be saying that if you've ridden a properly valved one. The stock valving in the front is horrid....if you ride on terrain with sharp bumps, that is.

 

Strange...I talked to John on two occasions and Rick at Cogent Dynamics who both independently stated the same thing about the main damper piston in the fork. Rick at Cogent ultimately purchased his own KLX250 and was able to get into the rebound stack and do some modding to it, but the main damper piston and compression stack are the real culprits.

Do the stock springs need to be replaced for the vast majority of riders?...yes. Will it stop the compression spike in the fork?...no. FD, I don't have any stock in Moto Pro, Race Tech, or other suspension companies.

 

I think we all agree:
-The bike with the hardest springs work better.
-If we get the maximum benefit that can deliver the fork so it is necessary to replace the valve. But it is an option, not required.