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Marzo Z1 SL Doppio: inop after oil change

MikeD

Leader and Demogogue of the Ridemonkey Satinists
Oct 26, 2001
11,669
1,713
chez moi
So I decided that rigid singlespeed just wasn't working for my local rides and decided to slap the suspension fork back on my hardtail.

2006 Z1 SL with the Doppio cartridge. Bought used, never opened it up or maintained it. It has always behaved a little strangely and I never thought I had the pos/neg air pressure thing figured out. "Travel adjust" always required a massive amount of negative pressure and it was always just a little nebulous what was going on; mostly I used it for a few years on some fairly mild riding so it wasn't ever a problem, although the fork was also never a stellar performer.

Decided that an overhaul was needed since it sat for many years; got new Enduro seals and Golden Spectro, ground a 12mm socket down to fit the foot nut recesses, and took it apart. Cleaned slider interiors with some Simple Green and greased the bushings with pure teflon lube. New seals went in without trouble and I reassembled the chassis and fastened the cartridges back in. [Edit: One small weird note--the (rider's) right-side cartridge has a 26mm hex, but the manual calls for a 21mm socket for both legs. Wrong cart in there?]

Used a syringe to measure out the oil 30ml (rider's) right side, 180ml left side called for in the service manual. Pumped each cart several times and reassembled. Now it's basically inoperative and super-stiff once any air pressure at all is added. Without air it'll move in a very damped manner but obviously without any feel of spring resistance. Right side seems to be almost completely full of oil when the fork is in the compressed position with top caps off.

Did I reverse the respective legs' oil volumes? (Edit: Manual seems clear, but...does seem strange that the spring side has so much oil and the damping side so little...in fact now I'm kinda sure this is the problem) Did I do something wrong when reassembling the carts? Any ideas? Marzo CS never wrote back to me...

I was just thinking it was time for a new fork, but decent non-tapered 20mm axle singlecrowns aren't that easy to find!
 
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Adventurous

Starshine Bro
Mar 19, 2014
10,262
8,770
Crawlorado
You are right that you mixed things up. The spring side should have little to no oil in the cartridge itself, only a little bit in the legs to aid the stanctions sliding through the bushings. The damper on the other hand should be almost completely filled with oil in the fully compressed state.
 

MikeD

Leader and Demogogue of the Ridemonkey Satinists
Oct 26, 2001
11,669
1,713
chez moi
Well, I checked the manual...I assumed the quantities referred to the legs on the rider's left/right, but maybe they mean as viewed from the front. I will open it up and try switching.
 

MikeD

Leader and Demogogue of the Ridemonkey Satinists
Oct 26, 2001
11,669
1,713
chez moi
Buon giorno, signore Marzocchi. It has been too long.

Yyyyup. That was it. Thanks for the sanity check. This thing is smooth as glass now.


On the downside I now realize how stupid it would be to lay out a few thou on that new Kona Hanzo Ti I really wanted, you know, because this old bike is all incompatible with the newest standards and everything. (If I'm gonna drop big money I should probably get the latest carbon full-suss allendubromountaintraill wunderrad to go with my old's-cool hardtail.)
 

valve bouncer

Master Dildoist
Feb 11, 2002
7,843
114
Japan
Buon giorno, signore Marzocchi. It has been too long.

Yyyyup. That was it. Thanks for the sanity check. This thing is smooth as glass now.
Ha, fucken rookie! Although in fairness I spent an hour once wondering why the dust wipers weren't bedding properly after a Marzocchi rebuild before turning them the other way up.
 

MikeD

Leader and Demogogue of the Ridemonkey Satinists
Oct 26, 2001
11,669
1,713
chez moi
Hey, hey now. I have an excuse. The manual was backwards, not me!

Seriously, they use "left" and "right" without defining (far as I can see) whether that's rider's orientation, or looking at it from the front. I used rider's right/left, which seems correct but is apparently NOT the Italian way...