[zeppman]

Hello,

Just did a lower leg service on my 2019 Fox 36 (fit4), and everything went smoothly until I went to re-pressurize the air chamber, and I noticed I have several millimeters less travel than before? Anyone know what's going on? It also feels a bit "dull" compared to before... My wife has the same fork/travel on her bike so it is easy to compare. I have not serviced my wife's fork yet.

Thank you.

 

[Shartist]

Did you equalize pressure in the positive and negative air chambers as you re-pressurized? Try depressurizing and pump it up again pausing in 25-50 psig intervals and cycle the shock a few times at each interval.

 

[zeppman]

Thanks for the reply, I did not at first... I know, stupid mistake I found after going back and watching some youtube videos.

I then released all air (which causes the stanchions to get sucked all the way into the lowers, is this normal?), and tried to adding air and equalizing every 5/10psi. This did not fix this issue.

 

[294037]

Did you install the lowers with the damper/spring fully extended? If it was compressed you can make a vacuum which sucks it down

 

[zeppman]

Thanks for the reply. They were compressed... I did that as it was easier to line up the lowers...

What do I need to do to fix this?

 

[RS VR6]

You can try burping the fork seal. Take a zip tie and stick it down in between the stanchion and seal. If you got air in there...you should hear a hiss.

 

[zeppman]

RS VR6, that won't hurt the kashima coating?

 

[Streetdoctor]

RS VR6, that won't hurt the kashima coating?

Not as long as you aren't using metal zip ties

 

[zeppman]

Not as long as you aren't using metal zip ties

Haha! Ok, thanks everyone. I'll give the ziptie a try tomorrow.

 

[RS VR6]

Use your fingernail to pull back the seal and stick the zip tie in. If there's air trapped down there it'll be released.

 

[zeppman]

So I tried the zip tie and I did hear a hiss. I did this at 10psi, and 52psi (my normal pressure) and again around 100psi. I then released all air, and brought it back to 52psi, doing the cycling/equalizing trick ever 10-15psi. It is still sitting at 120mm. It is a 140mm travel fork. My wife's identical fork is at 141mm.

Should I try pulling the lowers back off and re-assembling with both rods extended? Any other thoughts (that would be simpler)?

Thanks guys

 

[syl3]

if it got sucked down on depressurisation, you have a bit too much negtive pressure and your equalising dimple might have become clogged with slick honey.

depressurise again and force the fork to extend until you hear the piston reach the dimple, then its business as usual (pump up, equalise and so on)

 

[zeppman]

Thanks, I'll give that a try.

 

[Streetdoctor]

So I tried the zip tie and I did hear a hiss. I did this at 10psi, and 52psi (my normal pressure) and again around 100psi. I then released all air, and brought it back to 52psi, doing the cycling/equalizing trick ever 10-15psi. It is still sitting at 120psi. It is a 140mm travel fork. My wife's identical fork is at 141mm.

Should I try pulling the lowers back off and re-assembling with both rods extended? Any other thoughts (that would be simpler)?

Thanks guys

Are you an engineer? I wouldn't be worried about 1mm... It's a mountain bike fork. Go ride your bike!

 

[zeppman]

Are you an engineer? I wouldn't be worried about 1mm... It's a mountain bike fork. Go ride your bike!

Ha, I am! I have no problems with my wife's fork (141 vs 140mm), it's my fork that's lost 20mm.

 

[zeppman]

Really forcing the fork to full extension has seemed to work. Thank you all!