YZ450F Rear static sag

What sag are you running for cross country?

I have standard rear spring and when the riding sag is set to 92 mm my static sag is 44 mm. I weigh 90 kg. The manual says 90-100 mm for riding sag but nothing for static sag. I believe it should be around 35 mm, so I should perhaps have a bit stiffer spring for my weight? These bikes are factory tuned for a rider weighing some 75-80 kg.

For trail- and sand riding, better too soft than stiff.

15 to 25mm static with 95 to 105mm of rider sag, if you have too much static sag you need a softer spring !

on the contrary, Gizabious, if my static sag is too high I need a stiffer spring, not softer. In order to get my riding sag correct, I need to compress the spring too much cause I'm too heavy for the spring. And a well-compressed spring drops the bike too much when dropping the bike off stand! All this tells me only that I need to lose weight.

I have standard rear spring and when the riding sag is set to 92 mm my static sag is 44 mm. I weigh 90 kg. The manual says 90-100 mm for riding sag but nothing for static sag. I believe it should be around 35 mm, so I should perhaps have a bit stiffer spring for my weight? These bikes are factory tuned for a rider weighing some 75-80 kg.

For trail- and sand riding, better too soft than stiff.

Ditto :thumbsup:

If you set rider sag first at around 100mm and you end up with more static sag than you want then i think you need to change to a softer spring, if you set desired rider sag and end up with to little static sag then a firmer spring is required. Quite a few people i know run a slightly firmer spring to get a little more static sag (25 - 35mm) and like the way the rear stops kicking up. check out suspension forum. Also to have 44mm of static sag with 92mm of rider sag on the stock spring weighing 90kgs is strange, i'd say one of you're measurements is way out. There are loads of other threads covering this do a search to learn how to set up your suspension

hello Gizabious,

checked my sags: static sag 44 mm, riding sag 92+44=136 mm! No wonder the bike was not in balance. Changed to 30 mm SS

and now the RS is 109 mm. But I still need a firmer spring so that the spring is not so compressed as it is now, even though the sags are now close. Thanks for your suspiciousness. :thumbsup:

My sag is set to 95mm Per Race Tech Specifications.

The sag measurements for each bike vary a little. With most full size bikes look for a race sag measurement between 95mm and 100mm, and the static sag measurement ending up at a point between 15mm and 25mm, with 20mm being perfect. If you get your race sag properly set but your static sag is less than 15mm, you will need a heavier spring to correct this measurement. The same goes if the static sag is greater than 25mm, except a lighter spring will be needed to correct the measurement.

The process of measuring sag is exactly the same on smaller bikes, but the numbers change. On 80cc-100cc bikes the race sag measurements that we are trying to get to are between 75mm and 80mm with between 15mm and 20mm of static sag. On 50cc-65cc minibikes the static measurements will stay the same as the 80cc division, but the race sag is between 60mm and 65mm.

Bonzai :thumbsup:

Take this for what it is worth

I had my suspension done by a guy out here, (Aftershocks) Phil has been doing this for along time. I mean a long time.

He told me to set the bike up only for free sag at 7/8 of an inch. the rest will be fine

Ok I said, what about race sag. he said and I quote (Well Paraphased at Best) :devil:

The suspension is set up for your weight, we calcualted all that when you brought the stuff in.

With the new spring, valving and set up you reguested, setting free sag is all you need to do.

Sure enough, I set free sag to 7/8 and sat on the bike and the race sage set right into just shy of 4" :thumbsup:

7/8's of an inch is How much in mm again?

22.8600

That's within the ball park.

Bonzai :thumbsup:

Mine was way out; static sag 47.6mm Rider sag at 76.2mm for a total sag of 123.8mm. I set mine a little softer at the first because I'm short and like to touch the ground somewhat, but recently been have problems bottoming out in normal trail riding and the front diving in woops. I stiffined the spring a little and has eliminated bottoming out but still have the problem of the front dropping in the woops. If I reset this will this help in the woops? I just reset the SS to 15/16"(23.8125mm)and RS to 3 1/8"(79.575mm) for a total Sag of 103.3875mm. I guess I'd need a stiffer spring to increase the static and reduce rider sag right. I'm going riding tomorrow to see if it helps.

Sorry for the post, this was the wrong forum found it all out in suspension forum and refrence given by Davidyz450 without spending a dime. That's what this forum is all about right? People ask those of knowledge to share. At least it's not a post about which bike is faster, or is that rocket science? BTW it did take care of my problem no need for a new spring after all. It did feel a little stiff and took care of that with about 4 clicks softer on the rebound. Thanks anyway for the help guys!

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