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Card-carrying wotmeister
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Hey, guys who hopefully know more than I do.

My 55 ATA has been giving me trouble for a while, but now it's become unridable.

Basically, instead of stanchion length being what would normally be appropriate for the fork, like 175mm, only about 125mm of stanchion protrudes above the seals. I've wound the travel up and down several times to no avail.

I run 100PSI in the bottom leg's chamber and no PSI in the chamber under the ATA knob. Could this be my problem? Is there any way I can fix this myself without sending it to Marzocchi?

Thanks for any help.
 

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The chamber under the ATA knob is your main air spring. The lower air valve controls bottom out. You need to add air to the ATA, Marz recommends running the PAR (lower air chamber) 30 psi higher than the main.
 

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I just ran into the same issue this weekend. Fully extended I only have 135 mm of stanchion. When I crank down the ATA it goes to 90 mm. I've removed all of the air from the PAR and ATA multiple times and tried to reinflate to no avail, still only 135 mm of stanchion exposed. Not too sure if it's not time for a trip to Marzocchi.
 

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Chilling out
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if, somehow, don't ask me how, you get either too much air OR oil in the negative spring chamber (*not* the PAR chamber, but the negative spring chamber) you could see loss of extension/travel issues.

*IF* that's it, the bad part is you have to pull the ATA catridge out of the fork to relieve the pressure. The good bit is that this isn't the damper side so we're not talking about a lot of oil here - should be just enough in that side to lubricate (for my 66 ATA it's like 50mls, can't imagine it's much different for the 55 but you should look it up before exploring).

luck.
 

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when you take off the ATA cart top cap/seal slide it all the way up and down the shaft if it binds in any spot then you have one that got overclamped in production (early 08 had some) and then air will get sucked in and the cart gets stuck down.

My first 08 888 ATA cart did this but my 07 AM SL1 has been great and my replacement 08 888 ATA cart has had no issues.
 

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Just called Marz and described the problem with loss of travel. They seem to think that the O rings in the ATA cart have failed and suggested sending it in. Since the fork is going to be torn apart, I inquired about replacing the ATA cart with an ETA cart and they said it can be done for $110, so that's where I'm going. When I bought the fork, the idea of adjustable travel sounded really appealing but in the real world, I never really rode the thing anywhere but 125 or 165. Thanks to those who provided feedback.
 

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It's covered under warranty. Just call and get an RA#. They told me it would be a two week turn around. Also, it doesn't sound like an ATA failure just the o rings. If I knew what I was doing I would do it my self but I am also having issues with the TST.
 

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Anyone got some details on how to fix this?

After numerous other issues (leaky seals, cartridge failure, auto-wind down, loose bushings - still unresolved :madmax: ), my 2008 55ATA has also just stuck down at about 125mm - even though the cartridge has already been replaced once under warranty by Marzocchi.

That cost me many dollars for freight from Australia and six weeks with no fork :madman:, so I'd like to fix it myself if possible.

Has anyone done the ATA cart o-ring replacement or is there a thread with some details?
 

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No, that's not phonetic
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A friend of mine has an 08 66 ATA that became stuck down on one of our rides. It had all the classic symptoms of air escaping from the positive to the negative chamber. In earlier Zokes the negative chamber was independently set via an air valve and you could have fixed the stuck down simply by releasing this air. Now with an automatically set neg chamber you need to disassemble, and if stuck down rear shocks are any indication, the trapped air could pose a pretty serious danger when the cart is disassembled.
 

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Temporary fix (I think)

I have managed to release the trapped air in the ATA cartridge and get my travel back for now. I did this by removing the cartridge, deflating the air from the main spring and using the trusty inner-tube wrench and a spanner, opened the cartridge. This released the trapped air and a little oil and allowed the cart to fully extend again.

tscheezy said:
the trapped air could pose a pretty serious danger when the cart is disassembled.
Fortunately it was just a hissing noise as I opened the cartridge and wasn't too violent.

The fork rode like normal on a quick test run, but I expect it will stick down again over time. If I understand the problem correctly, air is escaping from the positive to the negative chamber and I need to replace the o-ring on the main piston. When it inevitably happens again, I will have a crack at this and post the results.

Again, if anyone has any experience with this process I'd like to know what I'm up against.

Bye-bye now.
 

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Sounds like the same problems my 08 55 has as well with only a few rides on it . I will be getting my fork back from Marzochhi any day now and they told me they are replacing the O-rings with actual seals that will prevent this type of malfunction from happening again? Has anyone had this done without further complication? Either way I guess I will find out in the next few weeks.
 

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its just a set of updated o-rings (at least last time I checked) and some are different sizes. I never had this happen on my 07 and it happened on my 08 888 but it was because of a different reason (ovalized travel rod) but everything is working good now and has been for some time.

If they now use a lip or cup seal it is very recent change but I dont see how they could since it needs to trap air from both sides pos and neg and a lip seal on the piston could only block it one way. Unless it has two lips one facing each way.
 
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