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"the sag rule"

demo 9

Turbo Monkey
Jan 31, 2007
5,911
45
north jersey
do you really benefit from having 1/3 of your travel as sag? 3 inches feels stupidly soft on my demo 9 and it bottoms everywhere and feels too soft to do anything and makes the bike dead. (cant wheelie or just rock garden sections) Am i supposed to have a really progressive shock? i prefer 1-1.5 inches but thats just me, i also come from a dirt jump backround.

feel free to talk, i know it bothered me and most of MY friends dont use this rule but the majority of the bikes i see use it.
 

Dogboy

Turbo Monkey
Apr 12, 2004
3,135
273
Chapel Hill, NC
30+% works well on most dh bikes. It kind of depends on what bike you are riding, but I can't think of a single modern dh bike that doesn't use at least 30% sag.
 

Inclag

Turbo Monkey
Sep 9, 2001
2,376
98
MA
Hmmm, I ran ~40% sag on a Demo 7 and bottomed probably all of 5 times last season.

I suspect either a) you are running more sag than you think or b) your shock is fugged.
 

DirtyMike

Turbo Fluffer
Aug 8, 2005
14,371
945
My own world inside my head
30-40% works excellent for DH, that is if you have teh right spring for your weight to begin with.

As far as a demo9, about 2.5 inches should be perfect, if your bottoming and your set at 3 inches, you probably have to soft of a spring.
 

demo 9

Turbo Monkey
Jan 31, 2007
5,911
45
north jersey
demo 9 and a yeti 303 yeti has almost 2 and the demo is 1 1.5
i tryed them both with less and bottomed alot. mostly 3 foots to flat but IT WAS AVOIADABLE if u "super absorbed "it


how do u know what works well?
 

demo 9

Turbo Monkey
Jan 31, 2007
5,911
45
north jersey
demo 9 and a yeti 303 yeti has almost 2 and the demo is 1 1.5
i tryed them both with less and bottomed alot. mostly 3 foots to flat but IT WAS AVOIADABLE if u "super absorbed "it


how do u know what works well?
also i tryed a TON of springs with 50 pound intervals. im keepin mine where its at but i was wondering what u guys did
 

demo 9

Turbo Monkey
Jan 31, 2007
5,911
45
north jersey
ok on the yeti a 400 by 3.0 with 75 PSI bottom on all the way on

on the demo 9 had a 500 by 3.0 on a **** swinger that had 50 PSI under minimum but i had to to make it ride ok, now i got a roco not sure yet
 

ZHendo

Turbo Monkey
Oct 29, 2006
1,619
97
PNW
if you're bottoming with only 15%-ish of sag, you need to loosen up and get a little smoother or get a new shock. if you aren't running the shock within its recommended pressure settings then you can't expect it to work for you.
 
personally, i like to have around 2 inches of sag for racing and less for FR or anything else... i have 9" of travel and use all of it quick on 5' drops to ~35 degree trannies... thats really only because i have a 350# spring on a rotec and weigh 185 geared...(with this spring i get almost 4" of sag with 3 turns preload and actually dont like it for bottoming issues... but it does give me a good idea of what sag i would like to have)
 

allsk8sno

Turbo Monkey
Jun 6, 2002
1,158
33
Bellingham, WA
mtbr has a better spring calc but you have to know something about your suspension, i run my bike with 20% sag but am a freerider with jumping roots...
 

djamgils

Monkey
Aug 31, 2007
349
0
Holland
everybody can bottom with drops to flat.

It probably also has to do with the fact that you run your swinger on 25psi. Chances are big that you will have cavitation, inconcistent damping and as a result bottoming out.
 

jvnixon

Turbo Monkey
May 14, 2006
2,325
0
SickLines.com
It also sounds like you might be running too little bottom out. I'd suggest calling FOX/Yeti and asking for shock setup tips as the 303 I rode was money and was setup by Mike @ FOX.

Granted I rode the bike on a real trail and not off curbs/steps to flat, but I never felt it really bottom out or blow through its travel and it tracked great on real terrain.

75psi in your bottom out seems like almost too little and perhaps shouldn't be ran full open either especially if you've got the right spring and are bottoming out that easy.
 

William42

fork ways
Jul 31, 2007
3,747
398
yeah dud3 seriously, my shockz alwayz bottom 0ut when I jump of my roof, I don't get it, I must need like 14" of travel!

fwiw, i'm about as smooth as sandpaper and I don't bottom out very often, even when i do something stupid like a 3 foot drop to flat. packing up under multiple hits? sometimes, but bottoming out? not really, and I'm not running an absurd amount of BOR on my tst.

maybe chill with the roof drops and focus on riding smoother? lift your legs a little and pull the rear end up over rocks from time to time

not trying to pick a bone man, but it seems like every week you're starting a thread about how you don't like your shock, it sounds like you've done the recommended settings, which makes me think focusing on riding style might be of the essence, and you could always try sending it out to push or somebody and tell them your problem and let THEM tune the shock for you.

just some food for thought.
 

demo 9

Turbo Monkey
Jan 31, 2007
5,911
45
north jersey
i dont mind my susupension now i like it, i was just wondering how many poeple ran more or less, my stuff is stayin the way it is.
 

William42

fork ways
Jul 31, 2007
3,747
398
ah, sorry i came off as a little harsh too, I didn't get any sleep last night and was pissed as a rat to boot. But after a day of shredding, everythings amazing!

and, in all fairness, I run relatively stiff for meastro (about 28% sag), but thats more because my shock packs up really badly otherwise. If I switched to a lighter oil, i'd probably have no troubles with the rebound, but I don't have the time for it.
 

stinky6

Monkey
Dec 24, 2004
517
0
Monroe
If 30% sag on a 9 inch bike is too much maybe you should be on a shorter travel bike; something with about 7", a 9" travel bike isn't for everyone. I'm in that situation; I have a 9" travel bike and it feels great, but I think I could get away with 7" bike if it was designed right. And I do run about 30% sag, but the bike isn't as quick as I would like. If you come from a dirt jump, skate park, or BMX background chances are DH bikes are just going to feel slow for your riding style. Those kind of bikes are just some much easier to move around.
 

Matchew

Monkey
May 26, 2006
511
0
NH / Mass (ugh)
I would try bumping up your shock pressure a bit; I weigh around 160 with gear and on my 303 I usually run about 90 PSI in in the boost valve with bottom out set set 3/4 of a turn from full open and ~35% sag on a 450# pound spring. I don't bottom out too often and I consider myself pretty smooth however, as previously stated, usually a bike that is set up for racing can easily be bottomed if you arent smooth to some extent.
 

Avy Rider

Monkey
Feb 26, 2003
287
0
Muskoka,Canada
I was easily blowing through the travel on my Fineline (Canfield F-1 inspired) bike until I spoke with Craig at Avalanche about properly setting my rear Avalanche shock with the High/Low speed compression adjuster.

Originally I thought that having the low speed compression settings soft and the high speed compression cranked up would make my bike ride right. I couldn't have been more wrong.
Turns out that dialing in more low speed compression and easing back on the high speed compression made the bike much smoother over small bumps and suck up bigger drops better.

Most bigger drops are not really activating your high speed valving as you are absorbing the initial impact with your arms and legs. Since you are now using mainly the low speed compression of the shock you will notice it can take these drops without blowing through as much travel if you run MORE LSC. Your bike will also feel more responsive and not so "wallowy."

If you're able to back off of the high speed compression without having it also decrease your LSC then the rear end can now quickly absorb true high speed bumps at full out speeds. As long as your rebound is set nice and fast the bike won't pack up on multiple hits either.

Just sound set up tips I got from a man who knows his ****.Worked for me and will likely hold true for most DH set ups. Of course not every frame has the same characteristics during the travel of the rear swing arm so try tweaking these settings.

1/3 of total travel in sag is optimal in most cases but not set in stone.
 
the funny thing is that for the few days i have had my Rotec and its been undersprung by about 100-150#'s, i have learned alot about flowing the bike into landings regardless of how smooth the takeoff was... the thing bottoms pretty quick and while i wouldnt mind it because i really cant feel it(Lawwill), i do because the tire slams the seatpost clamp and is kinda loud and bucks me a little...
but since i have told myself to make the most of having it and work my way around this problem until i get my new spring, i have worked more smoothness into my riding and it feels great and i can tell i'm improving somewhere beacuse my bike doesnt yell at me when i land harsh or overshoot...
while a reasonable amount of this has been because i push my front down when i know its coming, there have been many situations where absorbing the majority of the hit with the front is just out of the question... most of those have been loud, but i have taken into account what i did on the ones where i landed it smoothly for what it was...

anyways, if you and your bike can handle it, practicing this seems to be a good idea for helping your smoothness... but as i said, be sure your bike can handle it! or just go small with more sag...

but i still say personally i want to run about 30%+ sag for DH and around 20-25% for FR... the FR setup will probably be what i run everywhere but strictly DH and the setup will just be contingent on the compression cranks on my shock.
 

demo 9

Turbo Monkey
Jan 31, 2007
5,911
45
north jersey
im pretty smooth although i sound like a total newb right now i know. i like the way it rides with 3 inch sag. (both bikes) but it makes me slower because it seems like it slows down using soo much travel, and i cant gap certain rocks that easily because it takes me a good 10 feet to get the bike to "settle" so i can hop stuff, however with an inch and a half i am way faster, lil more bumpy, but i can gap whatever i need to and it seems faster-go figure. i guess im not a super softy kinda guy.

*but i am waiting for a 303 compatable CCBD*
 

Spunger

Git yer dumb questions here
Feb 19, 2003
2,258
0
805
Without sag your suspension is pretty useless. You have to have sag for everything to work correctly. I thought this was all funky too but try it, use that 25-30% sag rule.

I like forks that ride higher in the travel, but the rear has to have X amount of sag to settle into the bumps and ruts. I always thought something was wrong with my 5th element.........but it was all in the setup. Once set up right it rides like a dream.

The fact you can't make it "pop" is more of an issue with the rebound settings and such. If you crank it up you can get that pop you're looking for. For racing though you don't want that pop, you want it more glued to the ground.

Also noticed you have a 303........not exactly the "hucking" type of frame. If you pick one of the more huck friendly frame/shocks you might get what this frame is missing. Though it shouldn't be missing much! :)