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FOX TALAS fork % sag question

1K views 13 replies 4 participants last post by  SingleTrackHound 
#1 ·
To those who own TALAS:
when you guys set up the sag via air pressure in the main chamber based on the your rider weight, let say 20% to 25% at 5" travel (1" to 1.25"), does the TALAS system maintain the same 20% to 25% sag at 4" travel (meaning 20-25% of 4" travel therefore proper sag would be 0.8-1.0") as well? Or does it still maintain 1-1.25" sag from 5" travel at 4" travel? If that is the case, the sag becomes more like 25-31% at 4" travel mode, right? So if I want 20-25% sag at a 4" travel, I need to add more air pressure to main chamber?

If I understand the TALAS system correctly, it should maintain the same % in sag relative to traveling setting not the same inches of sag at 90mm or 130mm. Am I correct? Appreciate the technical insight to those who understands what I am after.

STH
 
#3 · (Edited)
I think so too!

Steve from JH said:
I haven't actually measured it accurately but it appears to keep the same percentage--i.e. if you lowered it from 5" to 4", sag would go from 1.25" to 1".
I was hoping that is how TALAS works so that I don't have to change the sag depending on where the travel is set to. So TALAS auto changes the sag to 20 to 25% where ever travel is set to but spring rate remains the same? Therefore fork will bottom out easier at lower travel setting unless prssure to main chamber is increased but will change the sag % value, right?

STH
 
#4 ·
SingleTrackHound said:
To those who own TALAS:
when you guys set up the sag via air pressure in the main chamber based on the your rider weight, let say 20% to 25% at 5" travel (1" to 1.25"), does the TALAS system maintain the same 20% to 25% sag at 4" travel (meaning 20-25% of 4" travel therefore proper sag would be 0.8-1.0") as well? Or does it still maintain 1-1.25" sag from 5" travel at 4" travel? If that is the case, the sag becomes more like 25-31% at 4" travel mode, right? So if I want 20-25% sag at a 4" travel, I need to add more air pressure to main chamber?

If I understand the TALAS system correctly, it should maintain the same % in sag relative to traveling setting not the same inches of sag at 90mm or 130mm. Am I correct? Appreciate the technical insight to those who understands what I am after.

STH
I never paid too much attention to the sag of the fork, I mostly went by feel, but I can say that however the spring rate adjusts, the fork "feels" the same at any setting. There is no need to change the pressure. This was on an '04. The TALAS system works very well.

Kapusta
 
#5 ·
SingleTrackHound said:
So TALAS auto changes the sag to 20 to 25% where ever travel is set to but spring rate remains the same? Therefore fork will bottom out easier at lower travel setting unless prssure to main chamber is increased but will change the sag % value, right?

STH
No, the spring rate increases as the fork is lowered. As you lower the fork, you are decreasing the size of the air chamber at full extention. A smaller air volume gives a more progressive spring rate.

Kapusta
 
#6 ·
I actually checked it today and it does keep the sag percentage just about exactly the same. This means that the spring rate increases, as Kapusta said. If the spring rate stayed the same, the sag would stay the same linear amount but that would be a larger percentage of the shortened travel. And since the spring rate increases, it takes about the same force to bottom it whatever the travel setting.
 
#7 ·
Then...

Steve from JH said:
I actually checked it today and it does keep the sag percentage just about exactly the same. This means that the spring rate increases, as Kapusta said. If the spring rate stayed the same, the sag would stay the same linear amount but that would be a larger percentage of the shortened travel. And since the spring rate increases, it takes about the same force to bottom it whatever the travel setting.
If spring rate does change with the travel setting, I wonder why Fox advertise their TALAS product as "...when you adjust travel, spring rate does not change, it feels same regardless of the travel...". Anyway, that is what's confusing me about this sag thingy. If spring rate did not change, fork would bottom out so easily at the lowest travel setting if you happened to set your sag at 5" mode or somewhere in the middle. Anyrate, I am with on this. Spring rate must change automaitcally if the % sag stays the same no matter where ever the travel setting is...reglardless what FOX says.

STH
 
#8 ·
My misread...

My mistake, latest Fox web site does say that the spring rate does appropriately change with each travel setting. Good because now I don't have to worry about carrying air pump when I ride and don't have to detrmine what travel setting I want to set the sag on.

Can't wait to mount 05 Talas I just bought for my bike.

STH
 
#9 ·
SingleTrackHound said:
My mistake, latest Fox web site does say that the spring rate does appropriately change with each travel setting. Good because now I don't have to worry about carrying air pump when I ride and don't have to detrmine what travel setting I want to set the sag on.

Can't wait to mount 05 Talas I just bought for my bike.

STH
You didn't make a mistake. The old Fox manual or advertising did say that the spring rate stayed the same and the fork felt the same. That's actually a contradiction and it was their mistake.
 
#10 ·
:confused: I've never owned a TALAS so I can't comment on the actual characteristics of the fork. I've only had a F100X and a Float but TALAS is supposed to mean: Travel Adjustable Linear Air Spring. So if the spring rate is not the same at any travel setting, I would be very interested to know.

Ronnie.
 
#12 · (Edited)
Ronnie said:
:confused: I've never owned a TALAS so I can't comment on the actual characteristics of the fork. I've only had a F100X and a Float but TALAS is supposed to mean: Travel Adjustable Linear Air Spring. So if the spring rate is not the same at any travel setting, I would be very interested to know.

Ronnie.
For any given travel setting, the spring rate stays close to linear as the fork travels in that setting. Move it to a shorter setting and the rate starts off and remains higher, but still close to linear.

Think of the Vanilla forks. If you have three travel settings, you're supposed to use three different springs, getting stiffer as the fork gets shorter. The TALAS is just trying to duplicate that effect but with a change in three mm increments and on the trail adjustability.
 
#13 ·
So am I...

Ronnie said:
:confused: I've never owned a TALAS so I can't comment on the actual characteristics of the fork. I've only had a F100X and a Float but TALAS is supposed to mean: Travel Adjustable Linear Air Spring. So if the spring rate is not the same at any travel setting, I would be very interested to know.

Ronnie.
So am I. I also own a Fox Float 100 RLC for almost three years and still do. I just bought a 2005 TALAS R becaue I liked how Float RLC rides. I bought TALAS R because I never used the lock out (all it does is raises the front ride height and stiff...not my preference) and compression adj could not be felt at all. So I bought TALAS R model and tried to save some $ but take advantage of travel adj on the fly. When I was thingking purchasing the TALAS, I was concerned about bottoming the fork too easily at low travel mode if I was to set the sag/spring rate at higher travel mode. Now that I have just suffered a bike injury and can't ride for another month or two, I won't be able to find out with an experiment to see if my concern was true. That's why I started this thread.

I guess I had this question beause I remember reading somwhere that TALAS does not change the spring rate but now new Fox web site seemed to have retracted that statement and does say that it does change spring rate appropriately with each adj on the travel knob. So this is what I think and based on the replies from other members I think it assures me that it is: Yes, springs rate does change appropriately (higher or less) when you turn the travel adj knob via some "magic" internal in the shock; I don't need to know what that magic internal is. However once the spring rate is changed, it does stay constant at that rate through out the stroke of the fork as long as you leave the travel adj at that newly adjusted travel setting. That way it would take same amount of force to bottom the fork no matter where the travel adj is set to. I am happy with my own explination until someone convinces me otherwise. Until then, I can concentrate on getting well so I can go ride soon and do less thingking.

STH
 
#14 ·
You are correct!

Steve from JH said:
For any given travel setting, the spring rate stays close to linear as the fork travels in that setting. Move it to a shorter setting and the rate starts off and remains higher, but still close to linear.

Think of the Vanilla forks. If you have three travel settings, you're supposed to use three different springs, getting stiffer as the fork gets shorter. The TALAS is just trying to duplicate that effect but with a change in three mm increments and on the trail adjustability.
Dido that!
 
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