2013 kx450f suspension

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11/11/2013 5:09 PM

I have a 13 kx450f I weigh about 265 what suspension should I buy for my bike ?


11/11/2013 6:06 PM

Race tech has a calculator on there website with spring rates, oil levels, ect.


11/11/2013 6:14 PM


It really depends on what you are looking for and your budget.

First and foremost, any suspension tuner will tell you first and foremost, get the proper springs in your bike. Since you have airforks, that's increase the pressure in the forks, and get a stiffer shock spring. You can calculate your shock spring rate via the Spring Rate Calculator on racetech.com to dial in exactly what you need. This will create the proper balance with your bike.

From there, the next step is oil. A fresh QUALITY oil will make a huge difference in suspension performance. Rebuilds are recommended every 20-30 hours (20 if it's still factory oil or a low quality oil). Oil moving through the suspension is what provides the action. The better oils will also reduce stiction (static friction) when the suspension moves, the smoother it moves the better consistency, traction, and feel you will get.

If you are looking for the most performance out of your suspension, you'll want to look into a full revalve with a reputable suspension tuner. This means going into your suspension and changing up your valve stack and many companies will either modify or replace your piston with an aftermarket one. Race Tech uses exclusively Gold Valves to create a better flow allowing for both a plush initial feel and great bottoming resistance. Valving is setup specifically for you, your bike, your skill level, and your type of riding. There is no better feeling in the world than properly setup, personalized suspension. You should notice a drastic increase in traction, the bike should be extremely predictable, and you'll feel much more "one with your bike".

A few things specific to the 13 KX450. The piston design in this bike has actually been brought back from about 10 years ago. Replacing the pistons is definitely encouraged on this model.

Also, with air forks, the heavier the rider, the more pressure you must run in the forks. We have found that increasing the pressure causes more pressure to be put on the seals and this causes additional stiction. For this, we recommend a revalve to put more emphasis on the valving to hold the front end up so less air pressure can be run to reduce the stiction. This will provide a better feel, more consistency, and more traction.

If you want to upgrade any of your suspension components, I would love for you to choose Race Tech. Through testing and tuning with top privateers like Derek Anderson and Cody Gilmore on this model, we've spent a ton of time developing and tuning, and all VITAL MX members are eligible for a 20% VITAL MX DISCOUNT.

If you have more questions or would like to quote an order, shoot me an email to chris@racetech.com.


Race Tech Director of Marketing
Proud supporters of VitalMX. Ask me about the VitalMX Discount!

11/11/2013 6:43 PM

^ now thats customer service


11/12/2013 7:52 AM

I personally recommend Race Tech. For me they were hands down better than Factory Connection, and as you can see, great customer service.


11/12/2013 7:31 PM


You weighing 265lbs is going to require you to run a higher air pressure then stock. When doing so, the PSF forks tend to become less compliant.

The best mod you could do to start is to get the next rate of stiffer balance springs (3.3N to be exact). These stiffer balance springs will help make your high air pressure more complaint and plush. Firmer valving will help the fork stay up, but that is not the primary variable to adjust. Air pressure is the primary input.

Everything else Chris stated above is true and correct. The Midvalve piston on that bike is not the best design and was updated for the 14 models. The new piston looks very similar to SDI Elite MV Piston that is featured on the RideJBI.com website.

I would recommend doing a shock spring at the same time also so the chassis balance is correct.

PSF Balance Springs
SDI Elite MV Piston


11/12/2013 8:44 PM
Edited Date/Time: 11/12/2013 8:45 PM

The mechanic for the Rocky Mountain MC supercross team lives about an hour away from me. I had him do all of my stuff. He did a killer job. The only thing is I can't remember if he used factory connection or race tech internals. I'm probably about your size also


11/12/2013 8:53 PM

Easy fix , put 2012 forks on it,lol.