Help on Piuma shock oil

piumaken · Post by **piumaken** » Sat Jan 26, 2008 11:19 pm

I'm about to rebuild the stock Marzocchi shock on my 1990 Piuma racebike. I've been unable to find any service information by searching on-line. Can anyone tell me what weight of oil is recommended for this shock? If not, I will have to try different oil weights until I find one that works properly, and that's a lot of work! Thanks for any help.

piumaken · Post by **piumaken** » Sun Jan 27, 2008 7:10 am

I think I solved my own problem. I noticed that the only reference to Marzocchi shock oil I could find was for their bicycle shocks. It said Spectro 125/150 suspension oil was a good substitute. I have a couple pints of that, so I decided to go ahead and use it. I've put the shock back together, and it feels pretty good. The resistance seems about the same as before without the spring, with a good range of damping going from one extreme to the other on the adjusters. The plastic sealing ring on the shock piston was pretty loose in the body, so I put a very thin brass shim behind it, and that removed the extra clearance while still letting the piston move freely. I'll have it back on the bike soon, and then I'll find out if it works properly, but I think it will. The damping mechanism is pretty unsophisticated compared to a modern sport bike shock, but it should work well enough for the occasional singles race.

Orry · Post by **Orry** » Thu Feb 28, 2008 5:11 pm

Hi,
what is quite important too is the amount
of shock oil you filled in.
do you remember how many ml you used?