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So humor me on a few sag questions, there's a reason I'm asking what I am.

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Do most of you agree that for specifically technical rocks and woods/trail riding sag should be a bit more than the standard mx amounts?

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I don't know, it seems to be widely accepted that you run more rear sag for enduro / trail riding. Personally I don't understand this.

1 - excess rear sag reduces weight on the front, this can actually make the front feel harsh as smaller motions may not have the force applied to overcome stiction / initial spring motion, transfering small bumps to the bars.

2 - excess rear sag increases take angle, which in turn aids high speed stability and reduces steering feel. Why would you want that for enduro?

 

Also, it seems to be widely believed that being 'further down the stroke' increases damping. I know progressive damping forks and shocks (KTM PDS?) exist. But on standard open cartridge forks this is not true, no additional ports are opened or closed when moving along the stroke, damping is dependent on speed, not position.

 

Also, soft is bad, (to me), the more I learn, the more I form my bike up. If you don't have enough damping (set your springs to Mx static and race rag) you can use your travel up quite quickly, now, when you have used half your travel as your low speed compression is overly soft, then you hit a square edged bump, there is the possibility that the amount of force required to initiate motion in the spring is not great enough (the same as now weight on forks), which can lead to an unnecessary harsh feeling.

 

As I understand things anyway...

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Oh, 96 bike with 07 ss forks, original shock.

But one things is you want more compliant susp for woods/trails than is needed for fast stuff.

Edited by Doggitter
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12 hours ago, moto_psycho said:

I don't know, it seems to be widely accepted that you run more rear sag for enduro / trail riding. Personally I don't understand this.

1 - excess rear sag reduces weight on the front, this can actually make the front feel harsh as smaller motions may not have the force applied to overcome stiction / initial spring motion, transfering small bumps to the bars.

2 - excess rear sag increases take angle, which in turn aids high speed stability and reduces steering feel. Why would you want that for enduro?

 

Also, it seems to be widely believed that being 'further down the stroke' increases damping. I know progressive damping forks and shocks (KTM PDS?) exist. But on standard open cartridge forks this is not true, no additional ports are opened or closed when moving along the stroke, damping is dependent on speed, not position.

 

Also, soft is bad, (to me), the more I learn, the more I form my bike up. If you don't have enough damping (set your springs to Mx static and race rag) you can use your travel up quite quickly, now, when you have used half your travel as your low speed compression is overly soft, then you hit a square edged bump, there is the possibility that the amount of force required to initiate motion in the spring is not great enough (the same as now weight on forks), which can lead to an unnecessary harsh feeling.

 

As I understand things anyway...

Your last paragraph is exactly what I am fighting now with my latest revalve. Forks a little too soft then too hard. Have not used the last 3in of travel in over two years. Hard to find the correct sag, balance F to R is difficult to find.

Edited by YHGEORGE

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There is no 'one' formula, just a variable baseline... Riding style, bike, speed, discipline, tire choice, suspension setup, etc all play parts... 

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43 minutes ago, YHGEORGE said:

Your last paragraph is exactly what I am fighting now with my latest revalve. Forks a little too soft then too hard. Have not used the last 3in of travel in over two years. Hard to find the correct sag, balance F to R is difficult to find.

It's the same with me. I know a lot of it is technique. I've got about an inch maybe an inch and a half unused travel, but I have my compression clickers 2 from fully closed. Going to convert the mid valve check plate to an actual mid valve, then soften the base valve a little and see what I get...

 

Apologies for the really obvious spelling mistakes, autocorrect!

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1 hour ago, Monk said:

There is no 'one' formula, just a variable baseline... Riding style, bike, speed, discipline, tire choice, suspension setup, etc all play parts... 

Boy, ain't that the truth!! 

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15 hours ago, Doggitter said:

Do most of you agree that for specifically technical rocks and woods/trail riding sag should be a bit more than the standard mx amounts?

I actually agree 100% for myself. I'm a slow rider in the nasty stuff and don't want to bounce around. I also soften the compression/rebound adjustments a few clicks when I know it's going to be a slow rocky trail riding day. 

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1 hour ago, ballisticexchris said:

I actually agree 100% for myself. I'm a slow rider in the nasty stuff and don't want to bounce around. I also soften the compression/rebound adjustments a few clicks when I know it's going to be a slow rocky trail riding day. 

I compare trials suspension to mine and it's like comparing a racecar to a rally car. One is stiff enough to benefit from fast, smooth tracks, the other soft enough to work with the rough stuff. My goal is to get more of the flex and movement so I can work the gnarly rocks, roots and ruts better. Not blast around smooth trails at flashy speeds.

 

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More preload = more stability for high speed but if you go too far she'll be harder to turn in and oversteer.

Less preload would prolly be better for slow speed rocks but can get a twitchy stink bug feel going on.

Edited by Casing-daily
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I ran across this yesterday and it's significant in that I can't get to 4" sag by backing the spring off before it's loose. The spring rate is 4.9 on this 96 250, I'm 185lbs. 

 

"All I can say is do it the old fashioned way. Measure the race sag at 100 mm. Then check the static sag and it should between 30-40mm. Some say 36 is the number to shoot for. If its higher than that then the spring is too stiff and if its lower its too soft."

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12 minutes ago, Doggitter said:

I ran across this yesterday and it's significant in that I can't get to 4" sag by backing the spring off before it's loose. The spring rate is 4.9 on this 96 250, I'm 185lbs. 

 

"All I can say is do it the old fashioned way. Measure the race sag at 100 mm. Then check the static sag and it should between 30-40mm. Some say 36 is the number to shoot for. If its higher than that then the spring is too stiff and if its lower its too soft."

Something not adding up here !!! 

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45 minutes ago, Casing-daily said:

More preload = more stability for high speed but if you go too far she'll be harder to turn in and oversteer.

Less preload would prolly be better for slow speed rocks but can get a twitchy stink bug feel going on.

That may be the most confusing post I have ever read. What end of the bike are you talking about? And finally, are you drinking?

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23 minutes ago, YHGEORGE said:

That may be the most confusing post I have ever read. What end of the bike are you talking about? And finally, are you drinking?

George, we're talking about sag aren't we? That's what the thread is about isn't it? Adjusting preload on shock spring is how you adjust sag is it not? I think people get confused about what more or less sag means, that's why I use the term "preload". What exactly do you need clarified? 

I worry about you sometimes George... I don't drink that's your gig.

Edited by Casing-daily

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I understand the preload-sag thing. What you are saying seems backwards to me. For instance less preload in the rear increases sag and does not produce a "stink bug" attitude. Just the opposite.  My understanding/experience is that a stink bug/twitchy attitude is a result of a too high rear which comes from too much preload, not less.

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1 hour ago, YHGEORGE said:

I understand the preload-sag thing. What you are saying seems backwards to me. For instance less preload in the rear increases sag and does not produce a "stink bug" attitude. Just the opposite.  My understanding/experience is that a stink bug/twitchy attitude is a result of a too high rear which comes from too much preload, not less.

More preload is tightening the spring down which lowers the rear. Less preload the spring is longer rear is raised. 

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16 minutes ago, Casing-daily said:

More preload is tightening the spring down which lowers the rear. Less preload the spring is longer rear is raised. 

Actually the opposite, the more you compress the spring / add preload, the more you raise the rear.

Proof is your free & race sag measurements which both diminish.

The higher the rear (more preload / less sag), with more weight on the front (also changes the geometry) it quickens steering but reduces straight line stability.

Edited by mlatour
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