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Got Any DH Questions? Ask Them Here
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flag ajax-ripper
Posted: Oct 30, 2014 at 15:11 Quote
At that point you still have more air volume trapped in the negative at a higher pressure. Re-inflating the shock may decrease the amount of stuck down but won't fix the problem... You may be able to un assemble the shock and re-assemble with the existing seals and fix the problem but it is likely to fail again.
flag Nobble
Posted: Oct 30, 2014 at 15:17 Quote
No, if you inflate the positive chamber to the same pressure as the negative chamber the shock should fully extend. Then the negative chamber should equalize and it will stay up.

A shock gets stuck down when air "burps" past the seal into the negative chamber.

I had the same effect happen on my boxxer air spring once when I was rebuilding it and let air out of the positive chamber with it compressed. The negative spring pulled it down.
flag ajax-ripper
Posted: Oct 30, 2014 at 15:23 Quote
Nobble wrote:
No, if you inflate the positive chamber to the same pressure as the negative chamber the shock should fully extend. Then the negative chamber should equalize and it will stay up.

A shock gets stuck down when air "burps" past the seal into the negative chamber.

I had the same effect happen on my boxxer air spring once when I was rebuilding it and let air out of the positive
Not the "negative coil spring"(Counter measure) but the negative spring created behind the plunger in the can. when air gets in here there is no where for it to exit. Pumping it up will allow for full extension at a very high PSI and it will not ride correctly. I've done many air sleeve services for stuck down shocks (given only one vivid). adding air will not fix the problem.

EDIT: Actually Try what noble said, i think you may be able to empty all of the air out if you remove pressure, cycle the shock, remove air, cycle, ETC. Forgot how the negative spring on these worked for a second.
flag Arnoodles
Posted: Oct 30, 2014 at 15:30 Quote
ajax-ripper wrote:
Nobble wrote:
No, if you inflate the positive chamber to the same pressure as the negative chamber the shock should fully extend. Then the negative chamber should equalize and it will stay up.

A shock gets stuck down when air "burps" past the seal into the negative chamber.

I had the same effect happen on my boxxer air spring once when I was rebuilding it and let air out of the positive
Not the "negative coil spring"(Counter measure) but the negative spring created behind the plunger in the can. when air gets in here there is no where for it to exit. Pumping it up will allow for full extension at a very high PSI and it will not ride correctly. I've done many air sleeve services for stuck down shocks (given only one vivid). adding air will not fix the problem.

EDIT: Actually Try what noble said, i think you may be able to empty all of the air out if you remove pressure, cycle the shock, remove air, cycle, ETC. Forgot how the negative spring on these worked for a second.
Pretty clear he's talking about the air negative spring, not coil. I've had the same with my rp23 when I was adding spacers. Equalizing the spring with a shock pump should fix it, but the seals might still be fudged.

EDIT: I should try reading the edits. Razz
flag Nobble
Posted: Oct 30, 2014 at 15:32 Quote
Remembered the negative spring now? lol

There's usually a detent in the air can that allows the pressure on both sides of the piston to equalize at full extension. Get it to that point and it should "reset" but the seals are probably fingered.
flag ajax-ripper
Posted: Oct 30, 2014 at 15:35 Quote
Nobble wrote:
Remembered the negative spring now? lol

There's usually a detent in the air can that allows the pressure on both sides of the piston to equalize at full extension. Get it to that point and it should "reset" but the seals are probably fingered.
I was thinking of the fox RP23 which had no detent nor a real negative spring... Serious brain farts occur sometimes Razz
flag Nobble
Posted: Oct 30, 2014 at 15:40 Quote
ajax-ripper wrote:
Nobble wrote:
Remembered the negative spring now? lol

There's usually a detent in the air can that allows the pressure on both sides of the piston to equalize at full extension. Get it to that point and it should "reset" but the seals are probably fingered.
I was thinking of the fox RP23 which had no detent nor a real negative spring... Serious brain farts occur sometimes Razz
RP23 does have a detent. I've put them on them.
flag ajax-ripper
Posted: Oct 30, 2014 at 15:42 Quote
Nobble wrote:
ajax-ripper wrote:
Nobble wrote:
Remembered the negative spring now? lol

There's usually a detent in the air can that allows the pressure on both sides of the piston to equalize at full extension. Get it to that point and it should "reset" but the seals are probably fingered.
I was thinking of the fox RP23 which had no detent nor a real negative spring... Serious brain farts occur sometimes Razz
RP23 does have a detent. I've put them on them.
You sure? I have one appart on my bench at home I'll need to take a look at it.
flag Nobble
Posted: Oct 30, 2014 at 15:46 Quote
Unless it was a really recent update...
flag ajax-ripper
Posted: Oct 30, 2014 at 15:50 Quote
Nobble wrote:
Unless it was a really recent update...
The early ones where prone to stuck down situations I believe these had no detent, I will check when I get home.
flag its-sam
Posted: Oct 30, 2014 at 15:51 Quote
knightridersix04 wrote:
rAtty-c wrote:
^ Marzocchi customer service is legit.

I just wish I could track down replacement parts for pre 2009 forks easier -_-
Marzo does a deal where you can trade in your older fork for 35% off a new one.

Linky??
flag Arnoodles
Posted: Oct 30, 2014 at 16:01 Quote
ajax-ripper wrote:
Nobble wrote:
Unless it was a really recent update...
The early ones where prone to stuck down situations I believe these had no detent, I will check when I get home.
The ones we were making 6 months ago had a detent...

Also the one on their site has it barely in the picture on the left side of the air can.
flag ajax-ripper
Posted: Oct 30, 2014 at 16:03 Quote
Arnoodles wrote:
ajax-ripper wrote:
Nobble wrote:
Unless it was a really recent update...
The early ones where prone to stuck down situations I believe these had no detent, I will check when I get home.
The ones we were making 6 months ago had a detent...

Also the one on their site has it barely in the picture on the left side of the air can.
The ones I'm thinking of where early model years (2004?) Irregardless there no point dragging this out much longer.
flag Arnoodles
Posted: Oct 30, 2014 at 16:07 Quote
ajax-ripper wrote:
Arnoodles wrote:
ajax-ripper wrote:

The early ones where prone to stuck down situations I believe these had no detent, I will check when I get home.
The ones we were making 6 months ago had a detent...

Also the one on their site has it barely in the picture on the left side of the air can.
The ones I'm thinking of where early model years (2004?) Irregardless there no point dragging this out much longer.
Aha. But yeah... To more interesting matters and beyond!
flag knightridersix04
Posted: Oct 30, 2014 at 16:19 Quote
its-sam wrote:
knightridersix04 wrote:
rAtty-c wrote:
^ Marzocchi customer service is legit.

I just wish I could track down replacement parts for pre 2009 forks easier -_-
Marzo does a deal where you can trade in your older fork for 35% off a new one.

Linky??
Go talk to your local dealer, they should be able to help you "cash in"

 


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