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Discussion Starter · #1 ·
Hey guys,

I got a new rear shock and set the sag on it to about ~30%, I went in to check what I was running at the front, I originally had it at 50psi, and measured only about 18mm sag. Sag was measured in attack position behind the saddle and chin above the stem off the saddle.

bike - ibis mojo hd
fork - 2012 fox kash 36 160 RLC
shock - 2012 monarch plus rc3

previously, I probably never really had sag set correctly, I just ran what I thought was safe so I don't buck off the front end with too low of a psi.

I put it at 25PSI, and measured about 32mm sag, my target would be ~30% (about 50mm).

What am I doing wrong here? What can I do to get the sag set up right for the fork? Thanks in advance, I appreciate it.
 

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Biking Like Crazy!
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How much do you weigh? If you are say around 150lbs then that psi isn't to far off.
And have you reduced the compression before setting sag?
Have you tried bouncing on the bike and then lean up against a wall and move the o-ring down to check sag?

EDIT: When was the last time you serviced the fork? It might need clean bath oil, and the fork is running a little gummy or sticky!
 

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Discussion Starter · #4 ·
I'm about 175 geared up, ya I bounced the suspension big time before zeroing out the o-rings, fork was just rebuilt from a talas to a float about ten rides ago, I haven't tried bringing compression to zero before sag, but I have a feeling it won't change much since I'm only at two clicks
 

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Hey guys,

I got a new rear shock and set the sag on it to about ~30%, I went in to check what I was running at the front, I originally had it at 50psi, and measured only about 18mm sag. Sag was measured in attack position behind the saddle and chin above the stem off the saddle.

bike - ibis mojo hd
fork - 2012 fox kash 36 160 RLC
shock - 2012 monarch plus rc3

previously, I probably never really had sag set correctly, I just ran what I thought was safe so I don't buck off the front end with too low of a psi.

I put it at 25PSI, and measured about 32mm sag, my target would be ~30% (about 50mm).

What am I doing wrong here? What can I do to get the sag set up right for the fork? Thanks in advance, I appreciate it.
First upgrade you should do is to the 2013 air spring assy. 2012 air spring I used to run about 50- 55 psi, with 2013 air spring I run about 70 psi.
I'm about 160 lbs. Don't know about sag , never use it. I set the pressure on the trail after multiple back to back test runs.
 

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Biking Like Crazy!
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darnelli, can you bottom out the fork when riding aggressively? Has the sag issue gotten worse since the re-build? Did you do the conversion yourself?
Sorry for the questions but need more info.
 

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Discussion Starter · #7 ·
when i was riding it around 45-50PSI i'd get maybe 75%-80% travel, issue has been about the same since the rebuild, i had trouble getting the sag to set on the TALAS too, nah the conversion was done by someone with experience (used to work at fox)
 

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Biking Like Crazy!
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Try letting all the air out and see if you can compress the fork to full travel.
You may have bleed more out when about 3/4 compressed. Also the Fit damper shouldn't be the problem.

I should add that when setting sag you should be in a normal riding position and not be behind your seat in attack mode.
Evenly weight both front and rear of the bike. Just a thought there also.
 

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I had the same issue as you before I rebuilt my fork recently. I noticed that there was way too much fluid in the air chamber (it somehow manages to keep up there from the lower bath. It should only have 5mm of fox float fluid. It seemed like a semi-common occurrence when I looked it up. Maybe depress all your air from the fork and take a 32mm wrench and open up the air chamber (from the top) and see how much oil is in there. If more than 5mm, this might be it.

Another thing you might try is inverting the fork/bike upside down and pressing the air valve to see if it squirts a little oil out with it. Just do a little. See if that changes anything. If so, check what I said before.
 

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Discussion Starter · #11 ·
thanks for the quick feedback, i've tried a few things this morning

• flipped the bikeupside down, let all the air out of the fork, a bit of oil came out
• flipped it rightside up, brought compression down to zero
• aired it up to 50psi, slipped off the spring compression ring on the SKF, slid a zip tie in on both sides and compressed the shock about 10 times
• filled it back up to about 37.5Ppsi, rode it around for a few mins, came back and bounced the suspension and got about 35mm sag

so it's improved a bit more than the number i was getting yesterday, still not at that 50mm sag setting
 

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Biking Like Crazy!
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thanks for the quick feedback, i've tried a few things this morning

• flipped the bikeupside down, let all the air out of the fork, a bit of oil came out
• flipped it rightside up, brought compression down to zero
• aired it up to 50psi, slipped off the spring compression ring on the SKF, slid a zip tie in on both sides and compressed the shock about 10 times
• filled it back up to about 37.5Ppsi, rode it around for a few mins, came back and bounced the suspension and got about 35mm sag

so it's improved a bit more than the number i was getting yesterday, still not at that 50mm sag setting
Sounds like your getting closer! While you had all the air out, did you see if the fork would compress an the way.
That would be a very good benchmark to know if anything was up with your fork.
 

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Sure it's not just the difference in a Float air spring vs a Talas air spring?. What year air spring did they use.If they've used the more linear 2013 air spring then you should be aiming for less sag as it's a more linear air spring. New seals as well so may need a bit of riding.

Have you ridden it? That's the proof, not the sag.
 

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Sure it's not just the difference in a Float air spring vs a Talas air spring?. What year air spring did they use.If they've used the more linear 2013 air spring then you should be aiming for less sag as it's a more linear air spring. New seals as well so may need a bit of riding.

Have you ridden it? That's the proof, not the sag.
Pretty sure the Talas air spring curve is going to be less linear than a Float's due to more seal drag and smaller air volumes, and the OP went from a Talas to a Float.
And yes he has ridden about 10 times already. I'm still waiting to here back if he gets full travel when all the air is let out and compresses the fork.
 

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Discussion Starter · #15 ·
yep with the air all the way out, fork compressed all the way down

i don't think it's a float talas thing, since i've had the same issue in both configurations, it was just built last year, not quite sure which air spring year it was, i could go find the P/N

but yea, i'll give it a ride tomorrow with it at like 40PSI (30ish mm sag), and see how it goes, I don't want it to wallow or pack down and get me into trouble
 

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Biking Like Crazy!
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yep with the air all the way out, fork compressed all the way down

i don't think it's a float talas thing, since i've had the same issue in both configurations, it was just built last year, not quite sure which air spring year it was, i could go find the P/N

but yea, i'll give it a ride tomorrow with it at like 40PSI (30ish mm sag), and see how it goes, I don't want it to wallow or pack down and get me into trouble
Yeah set the sag and ride it. If it does wallow, try upping the compression a bit.
If it does ride okay then I would have to maybe question the accuracy of the shock pump!
Remember to set the sag in regular riding position and not back over the seat. That would unweight the front to much.
 

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Discussion Starter · #17 ·
rode it out yesterday, at about 40 PSI, 2 clicks compression and 4 clicks rebound, felt pretty decent, didn't feel any dive or wallow really

the trail was just an XC type trail with roots and ruts and some rock garden sections

i used up almost all my travel in the shock and about 110-120mm of travel in the front (of 160)
 

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rode it out yesterday, at about 40 PSI, 2 clicks compression and 4 clicks rebound, felt pretty decent, didn't feel any dive or wallow really

the trail was just an XC type trail with roots and ruts and some rock garden sections

i used up almost all my travel in the shock and about 110-120mm of travel in the front (of 160)
If I were you, I'd increase the rear shock psi 10-15psi more and see that would make both front and rear use about the same amount of travel.
Seems like you might be a little light in the back and that would make the front end use less travel as your bike wouldn't be compressing parallel to the ground, if that makes sense.
 

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previously, I probably never really had sag set correctly, I just ran what I thought was safe so I don't buck off the front end with too low of a psi.
Well, this is what I do (with an exception). I start off with recommended psi/sag, and then adjust to what I like on the trail. I do not think I ever have the "recommended" sag, but close to it. I wouldn't worry too much that you do not get the "proper" sag, just go with what feels right. Try different air pressures with different rebounds and compressions. Oh, I have a 36 TALAS FIT that is tough to set up well (but I figured it out for me).

Only exception is the CC DB Air I am working with now. Found out sag was very important, as CC says.
 
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