Stock Suspension for 210 pounder

26 replies to this topic
  • grayracer513

Posted February 13, 2009 - 01:58 PM


...its amazing how people ... tell people to waste their money on exhaust, when that is the least important thing.

Suspension is an incredibly important, and far too often overlooked area where most bikes can be improved, and since going fast is around 80% rider, it's going to have more impact on the end product than an exhaust system in most cases.

However, with the '08-9, the suspension starts out so good, and the OEM exhaust is so bad, that's not always true for everyone. If he weighed 220+, or <165, I'd say the spring replacement was clearly more important, but here, the pipe should at least be near the top of the list.

  • grayracer513

Posted February 13, 2009 - 02:14 PM


(the '09) has the same springs as an '08?

Yes, it does.

  • mc1hd

Posted February 13, 2009 - 04:11 PM


I believe his is an '09.

Correct it is an 09, and as far as the stock header and muffler are concerned I got tired of it pretty quickly. I'm in the process of installing a complete 06 header and muffler and will post the results. Suspension can be a lot like the oil war's we all read about don't even want to go there. No one thing works for everyone.

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  • 08YZ450Derek

Posted February 13, 2009 - 04:48 PM


Nor Cal you are right, the shorty muffler sucks. Personal pref. is always different, but its pretty eventful that you will not like the exhaust setup. As far as Setup or any questions about these bikes, Greyracer is extremely knowledgeable on these machines.

  • Chriswells85

Posted February 13, 2009 - 06:29 PM


Im a big guy (6'1 280) Ive rode my bike with the springs and shocks on it, i dont know if the guy before me changed them or not... Ive been told my suspension was pretty firm... Where do i look to get suspension for my weight, and do the front shocks need changed?

  • grayracer513

Posted February 14, 2009 - 08:30 AM


You can determine whether your rear spring is the right rate for you or not by adjusting the race, or rider sag, then comparing it with the free, or static sag.

Race sag is the amount the the rear suspension compresses under the weight of the rider. The rider should have as much of his weight as possible on or directly over the foot pegs for this measurement. First, with the bike on a stand and the rear wheel hanging free, measure from the rear axle to some repeatable reference point. Then, with the bike on the ground, and the rider on board as described, take another measurement at the same two points. The rear suspension should settle a total of about 100mm (3 15/16"), with 97 or so (3 13/16") being preferable.

Free sag is the amount the bike settles from full extension when sitting on the ground under its own weight. Once the race sag is set, get off the bike, lift the rear fender a little, and let the bike settle under its own weight. If the rate of the rear spring is correct, the free sag will be about 25mm, or 1".

Now you can check the spring rate. If the spring is too soft, you will have to preload it too much to get 100mm of race sag, and the result will be that you have too little free sag, or none at all. If it's too stiff, you'll have too unwind it too far, and end up with more than an inch of free sag as a result.

At your weight, I would suggest that you first approach this test backward. Check the free sag first and set it to 25mm, then measure the race sag. If the race sag is pretty close, you can go through and do the process the right way around and double check. If, on the other hand, you find the race sag is way too much, you need heavier springs. I suggest this because there is a minimum length the spring should be preloaded to in order to avoid it coil binding, or bottoming against itself at full compression, and it's important not to exceed that limit. I don't have that info handy, and it's hard to measure it with the shock on the bike anyway.

Springs are almost always replaced as a set when people do it, so if the rear is wrong, the fronts most likely are, too. Springs are the single most important element of adjusting suspension for weight variances, and even at 280#, the right springs will probably put the damping within the range of the adjustment clickers, so by all means, start with that. I have among my riding pals a father and son duo who are both big guys at around 240-265, and when I resprung their bikes for them, they couldn't believe the difference it made.

Springs are available through any suspension shop, Smart Performance, Eibach, Cannon Racecraft, MX-Tech, Race Tech, etc. For your weight, Race Tech calls for 0.52kg/mm front springs and a 6.3 kg/mm rear.

Setting Race Sag

Checking Spring Rates

  • Chriswells85

Posted February 14, 2009 - 02:38 PM


Thanks Grayracer, i think thats the most clear answer possible, you are the man :lol:

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