how much sag ?

[rigger]

How much sag are you running on an average?

I have a lightly modded 04' 400EX. Suspension is stock. I am an aggresive trail rider.

Currently running about 3.5" - 4" of sag in the rear. I am about 165 lbs with out gear.

Just looking for some set up ideas and what you guys are running on yours so I can compare.

Thanks.

[TripleR400]

i would also like to know my description is the same as well...

This is from GTT:
Measuring Race Sag:

1. Race sag is the amount the quad settles from fully extended with the rider on board. First, put the quad up on a stand, measure the distance from the axle (vertically) to some point on the sub frame (make a mark if you need to).

2. Take the quad off the stand, put the rider on board standing on the pegs, have the rider hold onto something for balance, bounce up and down a little to stabilize the rear end. Now again measure the distance from the axle to the point on the sub frame where you took the measurement in #1.

3. Now deduct the measurement from #2 from the measurement in #1. This is your Race Sag.

4. To adjust Race Sag tighten or loosen the adjusting collars. If you have too much race sag, you need more preload, too little race sag you need less preload.

I have heard from full extension to when you sit on it it should be about 30% of the total travel. But there are variations in this so 30% is a guess. I would like to know what others have aswell for their 400ex. I am wanting to try setting up the sag to the right amount for hopefully a better ride.

[bradley300]

according to GTT, the 30% is a good number for a bike, but a quad does better with about 50%

[racernorris]

to add to your question: if a stock shock has 9" of travel, and a long travel shock set up has 10.5", would 30% or 50% work on both?
i go by tire size, 22" front and 20" rear, with you on the quad, in the front 8.5" from the bottom of the frame to the floor (measure in front of the motor), and 8" in the rear (measure from the bottom of the frame under the foot peg to the floor).
with that said, you may not be able to get these numbers with stock shocks.
for mx with 20" front and 18" rear, 7.5" in the front and 7" rear. hope i didn't confuss the issue.

norris
quinn motorsports

alright couldnt you do it like this?

Take the total travel of the shock and multiply by whatever percent to get the amount it should go down from where it sits to when you sit on it? Or is that incorrect?

EX: 400ex rear: (30% 9.1" x .3 = 2.73"),(50% 9.1" x .5 or 9.1/2 = 4.55") Would that work or no? I thin you would have to pull the rear up then let it down and sit on it to get a correct reading. Mine sags without me on it like i have upward motion on the rear if i grab the bar before the wheels will come off the ground.

[cmpearce]

if you are running stock shocks then 20% front and 30% rear

[rigger]

Now I grew up on bikes and set up on them for me is easy.

I am learning about atv set up, or at least trying to.

Now what follows is just me thinking out loud......
50% of the travel for race sag in the rear seems like a lot to me, but again I come from bikes too. 30% does not seem like it would be enough to do anything at all in rough terrain. IF you have almost no sag, then when you run over lets say a hole or come down the back side of a big whoop face, or log crossing, your rear end would not be able to drop into it allowing the tires to maintain traction which means forward momentum and control are lost and allowing you to lets say keep the front light for the next trail whatever is comming.
With 50% sag, it does not leave you with much travel left to absorb a hit. But, I am thinking if you are not on a track then 50% may be better in the woods. I do very little jumping, it is almost all agressive trail riding on rough, whooped out trails.

Now end to the thinking out loud....
I am currently running about 3.5-4" of sag at the moment. I need to remeasure to make sure. It does not handle the big whoops to bad, not like the bikes I used to ride but a lot better than what I expected out of a stock atv. I feel like if I can find that seet spot in the set up for my stock suspension, I should be able to hit that stuff pretty durn hard and keep on trucking. I still feel like the ride is a little harsh in the rear, and that is with compresion being backed out about 2/3 of it's range. ( I need to double check that too ) If I put a little more sag in the rear, softening that spring, it should affect that compression setting too. Also If I am thinking right, a softer spring setting should slow down the rebound effect because it is not pushing that shock back out so hard. In the whoops, to slow on the rebound means it will pack up, to fast and she will buck your a** right off. What I used to do for bikes was set it up fast at first, make it buck. Then slow it down a turn at a time until the bucking went away and rode it right there. That allowed me to get the most out of the bike charging hard in the whoops.

Guess what it boils down to is there is no magic number other than just go try some stuff. One of the places I ride has some good whoop sections connected by rough trail. I just need to go hit that spot over and over trying different set ups.

One last thing, does running more or less sag in the rear affect steering on an atv like it does on a bike. It makes dramatic changes in the way a bikes front feels both in steering traction.

Thanks for the thoughts guys. I am just trying to get the most out of my stock stuff because it will be a while before I really do any real suspension mods. Me, finding a second ride right now is my priority so my wife can ride with me again.

[400exrider707]

Good luck trying to get the stock stuff to do anything for you...:ermm:

[rigger]

Well I got to play with my shocks for just a bit today.
Set the sag at about 45% of the travel. Add a little mud and I know it will be at 50%. Took some measurements from the bottom of the frame to the ground too. I still sit a little higher than the 8 and 8-1/2'' measurements mentioned above, but was able to get the 1/2'' difference from front to back. I assume it is the frame angle you are trying to obtain more than the ride height.

Took it down the street where I can get to a very short little run through the woods. Really not very rough at all but it did feel a little different. The rear end seemed to settle down a little better and it felt like it turned a little better. It also pulled the front end off the ground better, 1st-4th, no problem.

This is now running the front shocks in the third position from full soft. Over all, it felt pretty good. But I won't really know until I get to take it for a real ride.

Race sag is another overlooked aspect--it's basically preload. If you have a single-spring rear shock setup, 30 percent of the total travel should be used in sag. Sag is the difference between an unloaded suspension and that with you sitting on your quad. The measurement should be taken at the rear axle. For an ATVwith 9 inches of rear-wheel travel, the sag should be 3 inches. You would also want about 10 percent free or static sag. That is the difference between your quad's normal rest position and that with no load at all--you can lift up on the grab bar and extend the suspension or put the machine on a stand to get this measurement. On an ATV with 9 inches of travel, it is just less than an inch. If you are too heavy for the spring rate, you will have to crank in so much preload to get the 3 inches of race sag that you'll end up without any free sag: The only solution is a stiffer spring. Conversely, if you are too light and unable to get the 30 percent race sag with 10 percent static sag, a lighter spring is needed.



So if I read this right from the normal position you should be able to lift up just over an inch before your tires lift off or till you feel the suspension go no farther up. And when you sit on it it should go down 3". And this is all for a 400EX basically because the example is 9" of travel 400ex is 9.1".

[TRXRacer1]

Originally posted by racernorris
to add to your question: if a stock shock has 9" of travel, and a long travel shock set up has 10.5", would 30% or 50% work on both?
i go by tire size, 22" front and 20" rear, with you on the quad, in the front 8.5" from the bottom of the frame to the floor (measure in front of the motor), and 8" in the rear (measure from the bottom of the frame under the foot peg to the floor).
with that said, you may not be able to get these numbers with stock shocks.
for mx with 20" front and 18" rear, 7.5" in the front and 7" rear. hope i didn't confuss the issue.

norris
quinn motorsports Do not set sag this way. Each quad has different geometry and setting sag by measuring off the frame like this will yield inconsistent results.

bradley300 is right, 30% is still too stiff for this bike. I've been at 50% for a couple years now and love it! If everyone set the 400ex rear at 50% there would be a lot less revalving going on.

[rigger]

So many different thoughts on the same subject. Only way to know is go out and try different set ups. Most bikes that I have had with the exception of my last 04' KX250, I was always able to adjust the suspension to where it worked pretty well and I did not feel the need to spend money on it to be worked over.

I might have time to go ride this weekend and if I do, I will be hitting some rough and whooped out trails. It will be a good test for my new suspension settings.

All I can do is try it. I will let you know how it goes.

[racernorris]

i haven't tried to set the sag on a stock shock since my first 250r in 1988, since then all the shocks that i have set up have been re-valves or after market shocks. the re-valves i build for the rear are dual rate and its easy to set the sag on this set up. the none rebuild able shocks on several production quads are not something i deal with every day, but the rebuild able shocks are.
90% of my customers are racers, gncc, gnc, wpsa, and local mx.
but some of my customers are trail riders looking for a better ride.

comparing a motorcycle to a quad? a quad weights twice as much as a cycle and has some what less travel. if you look at how much the stock motorcycle suspension has progressed in the past 20 years. com pair the 86-89 250r wheel travel to the 2008 450r, not much has changed except for the quads gained weight.

i don't mean to say that you can't adjust stock shocks to ride better. there wouldn't be some many companies building shocks if the manufacturers redesigned the qauds every year like they do the bikes. enough said!

norris
quinn motor sports:macho

[bradley300]

to the guys comparing with the bikes-

remember tire sizes are way taller on a bike, so they dont need near as much sag to get thru the same hole, compounded by the fact that they have more travel (which is more sag w/ a smaller % of travel)

[rigger]

I was not trying to really compare bikes and atv's. Thats really not something that you could compare fairly. They are just way to different. I was just saying that with some time and playing around with it, I was just about always able to adjust out my bikes for the way that I ride.

I grew up on bikes. With the atv's, this is a learning curve for me. I will play with it untill I get it to where I am happy with it or, I will get it the best I can and when I have the money to get good stuff for it, I will.

Until then, I just want what I have to work the best that it can.

I did not get to go ride my 400EX this past weekend because I had to go get my new, (used), rideable project Banshee to add to the garage.

I just checked the sag on the rear measuring where the back bar goes. From it sagging itself and me pulling up from that point it was about 1.5" and when I sat on it, it was around 2". So I assume I need to loosen it a bit to make it sag a little bit more. Although with gear on i'm heavier.

[bradley300]

i would say so. remember with stock shocks you might not be able to get it to sag as much as you need depending on your weight (you dont mention aftermarket shocks in your sig). if you cant,. just get it as close as you can. with your 400ex set your rear sag, then measure the ride height at the footpegs. then measure at the rear a-arm mount for your front ride hieght, it needs to be between .25 and .5 inche higher than the rear

[trail11591]

wat about a trx 450?? how would u measure that and how much difference should it be??
thanks

Alright I set up my suspension in the rear today. Tomorrow or something I will post pictures on what and where to measure and what to do. I got mine to be pretty perfect 1st try setting it. The rear when you measure rear a-arm mount and foot pegs the difference is almost exactly .5", I got the rear to have almost the perfect numbers for the up and down travel.

[Fenix169motox]

ok guys i think i know what you're talking about for the rear sag, but how much should the front sag? I have stock 450r shocks on my 400ex so they;re adjustable and all that sweet jazz.
In our Honda specific class we were told honda recommends 1 inch of static sag and 4 inches of riders sag, but thats only the rear..

[bradley300]

dont worry aout sag on the front. once you get the sag set on the rear, the rear ride height will also be set, so take the rear ride height, add .25 - .5 inches for the front ride hieght ( .75 if your on a yamaha)

[bradley300]

Originally posted by FoxHondaRider
Alright I set up my suspension in the rear today. Tomorrow or something I will post pictures on what and where to measure and what to do. I got mine to be pretty perfect 1st try setting it. The rear when you measure rear a-arm mount and foot pegs the difference is almost exactly .5", I got the rear to have almost the perfect numbers for the up and down travel.

as for where to measure, i go from the axle to a grab bar bolt

[Fenix169motox]

Originally posted by bradley300
dont worry aout sag on the front. once you get the sag set on the rear, the rear ride height will also be set, so take the rear ride height, add .25 - .5 inches for the front ride hieght ( .75 if your on a yamaha)

well wont if i have practically no sag up front when my front tires wont drop down at all if i come across a hole and all that? there's got to be at least a little, right?

[TRXRacer1]

Originally posted by Fenix169motox
well wont if i have practically no sag up front when my front tires wont drop down at all if i come across a hole and all that? there's got to be at least a little, right? He's saying set the front sag in proportion to the rear. The only problem is that with all the different tire height combos you can have the front won't always be .25-.5 inches higher then the rear when properly dialed in.

the .25 - .5 front to rear difference, is that while sitting on it or the machine sagging itself? Mine has just about .5" without me sitting on it and my rear is almost perfect on how much it sags. Unfortunatly the stock front shocks are only preload adjustable so setting the sag doesnt work too good. My shocks need to have more preload on the front so I bottom out less. When I got the 400ex the front was on the 1st setting which is super soft and I would bottom out a lot. I moved it to the 3rd position where I am now, and I feel myself bottoming out too much now. I only weigh around 155LBS or so with gear on. Its just the fact that I am constantly trying to go bigger because I know my quad more. 450r front shocks is my plan...

[Fenix169motox]

ok so are you talking about .5 or .25 inches or percent?

I hacve 21 inch front tires and 18 in the rear, with 450r front shocks,

so what would my static and riders sag be????


<-----lost

[bradley300]

Originally posted by Fenix169motox
well wont if i have practically no sag up front when my front tires wont drop down at all if i come across a hole and all that? there's got to be at least a little, right?

correct sag is a natural product of correct ride height and vise versa, assuming the shocks are also correct. the rear shock is very important since it takes twice the bumps as the front. so, in order to make sure you have the rear shock perfect you measure sag because tire sizes vary, you dont measure the ride height, the sag is more important. so once the rear shock is right, you can adjust the front ride height accordingly and it will have the right sag.

basicly, if the rear sag is right, the rear ride height is right, if the rear ride height is right, adding .25-.5 inches for the front ride height and it will be right, if the front ride height is right, the front sag will be right

[bradley300]

Originally posted by FoxHondaRider
the .25 - .5 front to rear difference, is that while sitting on it or the machine sagging itself? Mine has just about .5" without me sitting on it and my rear is almost perfect on how much it sags. Unfortunatly the stock front shocks are only preload adjustable so setting the sag doesnt work too good. My shocks need to have more preload on the front so I bottom out less. When I got the 400ex the front was on the 1st setting which is super soft and I would bottom out a lot. I moved it to the 3rd position where I am now, and I feel myself bottoming out too much now. I only weigh around 155LBS or so with gear on. Its just the fact that I am constantly trying to go bigger because I know my quad more. 450r front shocks is my plan...

dont make any adjustments without you on the bike. when is the last time you rode it while you werent on it? all adjustments need to be with rider because that is the most important thing is how it i set up while you are riding

[bradley300]

Originally posted by Fenix169motox
ok so are you talking about .5 or .25 inches or percent?

I hacve 21 inch front tires and 18 in the rear, with 450r front shocks,

so what would my static and riders sag be????


<-----lost

1. inches.

2. dont worry about your static sag. just worry about your rider sag, nothing else will be right until the rider sag is correct.

[bradley300]

Originally posted by TRXRacer1
with all the different tire height combos you can have the front won't always be .25-.5 inches higher then the rear when properly dialed in.

if the shock builder knows the exact tire sizes then you can have a perfect front end. the problem is as you said there is variance in tire sizes, even within a brand.

lets say you tell your shock builder the EXACT tire sizes, they can set up a perfect front end for you

now lets says all he ask if what do you race. you say MX, so the builder assumes 18 inch rears and 19 inch fronts. if he's right there will not be a significant issue since the tires sizes only vary a half inch of so (it is enuff to really mess with the rear, which is why you dial the rear sag not the ride height. to make sure he shock is perfect, not the frame)

the issue comes in with someonle like Fenix169motox (sorry to pick on you, i just know what your tires sizes are). he is running an oddball size front tire. if he wa not asked what size front tires he has, his supsension will never be as good as it should. once he sets his rear sag/ride height and moves to the front he will hve to really take out preload form the front shocks to get his front ride height correct because the tires are so tall. he can get his ride height correct with the big tires, but its now a compromise, perfect ride height vs. correct sag. correct sag and his front end sits way too high ( little weight bias towards the front end, wont turn as well as it should) or his ride height is correct and has too much sag and bottoms easy.

this is why you want a shock builder that asks a ton of questions and why tire sizes mean way more than most people think

[bradley300]

as for why do you want the front higher than the rear.

1. more weight bias to the rear tires that provide grip.

2. you are adding rake (tilt back) to the a-arms so the suspension doesnt hit on object straight on. this keeps the suspension smooth

ever wonder why a yamaha never seems to turn as well as a honda? hondas have more rake built into the frame so they dont need as much more ride height in the front than the rear. this keeps the weight better distrubuted which is why they generally turn and brake better than a yamaha. conversely, the yamaha only has about 7 derees of rake (vs. about 14 for a honda) so it needs that extra ride height to glance off bumps instead of hitting them so harshly, the down side is the generally dont turn or brake as well as a honda because of the more rearward weight bias needed to get the front end to work its best

there are other resons like spindle/frame design, but we wont get into that

[Fenix169motox]

ok? and they've gotta be 20's up front then but i understand what you're getting at, but all im wondering is the numbers, i have stock 450r shocks, and the stock 400ex rear schock, how much sag for the rear and how much sag for the front?

30% of the shocks travel? or its length, cuz thats adjustable.. and how many inches of sag up front? 1/2" ?

Thats what im lost on now..

I havent rode it much at all with the 450r shocks, and they feel stiff as can be, its why im curious about sag and all that.

i vaguely (sp??) know whats going on i just need the numbers..

[Fenix169motox]

hey i have a 1.25 ext swing arm too should the rear sag be the same still?

[bradley300]

Originally posted by Fenix169motox
ok? and they've gotta be 20's up front then but i understand what you're getting at, but all im wondering is the numbers, i have stock 450r shocks, and the stock 400ex rear schock, how much sag for the rear and how much sag for the front?

30% of the shocks travel? or its length, cuz thats adjustable.. and how many inches of sag up front? 1/2" ?

Thats what im lost on now..

I havent rode it much at all with the 450r shocks, and they feel stiff as can be, its why im curious about sag and all that.

i vaguely (sp??) know whats going on i just need the numbers..

the rear sag will be different because you have added to the length of the swingarm, you have added travel. the percentage is the same tho (50%) i would bet with a +1.25 swinger you are around 11 inches of wheel travel in the back, 50% of that should be rider sag, so about 5.5 inches

your front shocks wont be right regardless of what you do because they are too long for a 400ex. you can either play with them to get them as good as you can, or you can have them cut down and revalved so they work right (plenty of shock builders do this). the principles i explained with having too big tires applies with too long shocks also. i'm honestly not sure what the sag % in the front should be, becasue ive always worked with a matching set of shocks. i would bet if the rear sag is 5.5 inches, the front would be right at 5, since you are raising the quad a half inch higher in the front.

just set your rear sag to 5.25-5.5 inches measure then rear ride height, add .25 inches for the front ride height and go from there, it should be a good starting point. since the 450r shocks are longer, they will probably have too much sag if you have the ride height correct, but at least you will have a starting point. raise the ride height from there maybe .25 inches at a time until you can feel the best of both worlds (if you can even make them short enuff with the adjustability you have in the preload to begin with)

[Fenix169motox]

ok sweet, thanks!

So rear is 5.5" roughly..
And front is 5.25" of sag?


Measureing ride rear ride height from the the rear of the frame, and the front ride height from the up bend where the a arms bolt up?

and i'm planning on gettng my shocks rebuilt for a set of +2 a arms and all that when i find a set.. which is harder to do than understand all these percentages lol

Originally posted by bradley300
dont make any adjustments without you on the bike. when is the last time you rode it while you werent on it? all adjustments need to be with rider because that is the most important thing is how it i set up while you are riding

I made the adjustments for sag while I was on it but the thing where its supposed to be .25" to .5" difference between the front and rear I didnt measure with me on it. The rear is almost perfect andwhen i measured I got .5" difference without me on the quad. I have 21" fronts and 20" rears.

[bradley300]

Originally posted by Fenix169motox
ok sweet, thanks!

So rear is 5.5" roughly..
And front is 5.25" of sag?


Measureing ride rear ride height from the the rear of the frame, and the front ride height from the up bend where the a arms bolt up?

and i'm planning on gettng my shocks rebuilt for a set of +2 a arms and all that when i find a set.. which is harder to do than understand all these percentages lol

measure the rear ride height under the foot peg, then measure 22inches foward of that (it happend to be the rear a-arms mount on my yfz) and measure the ront ride height there

for the front, that is just an estimate since i've never done front sag. but, knowing the rear sag, and knowing that the front needs to be .25 to .5 inches higher, that geustimate makes sense.

and for new shocks, send those stock 450r shocks out for a rebild, save you some money and they will be better than an off the shelf shock like elka

[bradley300]

Originally posted by FoxHondaRider
I made the adjustments for sag while I was on it but the thing where its supposed to be .25" to .5" difference between the front and rear I didnt measure with me on it. The rear is almost perfect andwhen i measured I got .5" difference without me on the quad. I have 21" fronts and 20" rears.

i would check the front with you on it just to make sure, and i would double check the rear also