suspension help

14 replies to this topic
  • precision28

Posted August 12, 2002 - 03:52 PM


I am new to motocross and need a starting point to help me with my suspension springs,compression, rebound the works I am 200lbs riding a 426 could I please get help on setting my bike up especially riders close to my weight with their settings

  • TAC

Posted August 12, 2002 - 05:23 PM


I put a 5.6 shock spring and .48 for springs in my bike. I have also found that tightening up rebound dampning has taking the hit out of the bike as well as made it so itdoesnt feel like it is trying to throw me of s bad but adjustments need to be made to your what you prefer. i have also had the valving changed.

  • DaveJ

Posted August 12, 2002 - 07:22 PM



Is there something you're not happy with?


  • Cobra314

Posted August 12, 2002 - 07:42 PM


  • barnum

Posted August 12, 2002 - 08:09 PM


Hi Dave,
I have alot of racing experience with the YZF model. I am in the 200 lb range also. I would say that you do need a little heavier springs.The 5.6 shock spring and the .48 fork springs would be very close to what you need. But more important is the internal valving that needs to be done. IT is very important to releve the harsh initial compresion dampening. For example Braking bumps ,pot holes, washboards. A good setting for your clickers is.
Shock comp @ 14
Shock reb @ 14
Fork comp @ 16
Fork reb @ 14
This is a good place to start for MX.
If you would like some help with your parts or revalving feel free to email me at
Thank Rob Barnum.

[ August 12, 2002: Message edited by: barnum ]

  • dmxracing

Posted August 12, 2002 - 10:07 PM


Hey Rob, do you work for a shop? Do you revalve? I need my suspension revalved and I need new springs. I am 6'2" and 220lbs.



  • precision28

Posted August 13, 2002 - 05:51 AM


the thing that I not happy with is my front forks are bottoming out I added 10 ml of oil this helped a little but it is still bottoming on occasion, on the rear it feels like if i don't land a jump perfect the bike bounces off the landing. I have been going to some races I have noticed that some riders are comming up a little short like my self but there suspension absorbs the miscue mine wants to throw me

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  • 98yz

Posted August 13, 2002 - 06:50 AM


precision28, I am 195 lbs and ride a 01 426. The stock springs can more than handle your weight depending on your riding ability. I am a B class rider. If you make it a habit of landing rear wheel first it will be hard to stop the forks from bottoming no matter who builds them or what is done with them. I just built the suspension on a WR 426 and set the suspension up to the YZ specs with a 5.4 rear spring (rather than the stock wr 5.0), and left the .46 fronts. The bike has a super plush ride and can handle over jumping almost anything without punishing the rider.

Most important first step is to make sure everything is set to a good starting point. Make sure sag is correct and start with clickers at a mid way setting and begin to adjust from there. If things are jacked up to start with it is hard to tell what you need to do to fix the problems. Also try your best to make sure you are in the right position on the bike.

[ August 13, 2002: Message edited by: 98yz ]

  • sirthumpalot

Posted August 13, 2002 - 07:15 AM


Try slowing down (turn in) your rebound, that should help with the bounce effect. I'm in the neighborhood of 5 or 6 clicks out in both the front and the back and I no longer bounce off of tabletops when I come up short. You can probably add more oil to the forks, the manual will give you the max oil height. You weigh a lot more than me so the settings might not work for you but it's as easy as turning the clicker so it's worth a try. The stock settings had me bouncing all over the place.

  • precision28

Posted August 13, 2002 - 07:40 AM


98YZ what is a good oil hieght to run ? I am currently 120ml
thanks steve

  • DaveJ

Posted August 13, 2002 - 08:35 AM



Thanks for the reply.

Of course it's good to know what your concerns are before you make any modifications regardless of how small or large.

And any good suspension shop should have a long chat with you on this matter before they take your forks in for work, and certainly before they take your money.

98YZ and Sirthump have some great input, (as always). And I agree that you may want to stick with the .46 springs.

Such a message from them and myself comes from experience. A stiffer spring will help, but the bike will then suffer dramatically in the corners since it won't dive like it should.

You're forks are just moving too quickly, both in and out (compression and rebound). To slow it down, start with adjustments to the clickers.

The best way to approach this is to turn all four screws all the way out. Then add rebound until you're bouncing back issues go away, without a loss in recovery. THEN add in compression until the bike gains stability. Keep in mind that you only adjust in the least amount you need.

If this fails, you may need to revalve. A process that is rather simple and actually very inexpensive. Probably less than $10 with the right tools.

As for adjusting oil height, as these guys have mentioned, is also a good idea. But as with stiffer springs, too much oil will not allow the bike to dive and turn. In other words, don't resolve a compression (valving) problem by adding more oil.

This mentality of knowing what is wrong and how to correct it is key to setting up your suspension. Understand the difference and effects between rebound, compression, springs, and oil height and when to adjust each for a particular problem.

The goal is find the find the right balance between all four attributes without any sacrifice in the ride. For example, more oil or a stiffer spring may fix a problem, but it introduces other complications.

Hope that makes sense and stay in touch with the board. Many of these guys really know their stuff.


  • John_Curea

Posted August 13, 2002 - 05:10 PM


precision 28

I agree with davej, the springs are correct for your weight.

How much time is on the forks? If anything over 30 to 40 hours, I would recommend a COMPLETE teardown and inspection. The midvalve compression face shim usually gets distorted (aka. "blown midvalve").

You will be suprised what a complete rebuild will do for your forks. I would recommend this action first since you said you were just starting out. Spend the money you save on good tires.

Click on the link below, it will take you to our mx-tech website, with detailed directions for a complete rebuild.

web page

  • precision28

Posted August 13, 2002 - 06:34 PM


thanks for the information. john where is mx tech located I noticed the logo said east coast

  • marion

Posted August 13, 2002 - 07:05 PM



Do some Precision riding time on your bike before you start requesting info that you don't understand.
Go to your local track and do some major suspension testing. Play with all your clickers, take notes, you'll be plesantly suprised.

It will be an all day affair, at the completion of the day, you'll know more than 99% of the riders out there.

Good Luck

PS Your bike probably dosen't need work.

  • 98yz

Posted August 15, 2002 - 05:37 AM


precision28, I run my oil level at 95mm. I typically set most of the YZ's that I build up at 95 to 100mm oil height. I use both Race Tech and Moto-Pro components (usually based on customer preference). The last bit of info in not really important except to say that even with different suspension components it seems to hold pretty much the same with the oil height to get very similar results.

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