Going to attempt a service on my Marzocchi Z3 forks at the weekend. does anyone have any recommendations for oil?

Rock Oil or Silkolene are fine. Just make sure the weight is the correct one from your service guide.

Putoline also good… As are some other brands not yet mentioned yet but I can't think right now.

Just make sure it's fully synthetic Motocross fork oil you're buying, not the cheaper stuff.

Oh, and for a Marzocchi fork, unless you're very light or very heavy, it'll be 7.5wt fork oil you need.

Silkolene comes in pretty colours, so I use it. Though I seem to remember a rumour that silkolene doesn't mix with Marzocchi seals- I strongly suspect it's cobblers but you never know.

Trouble is that fork oil viscosity actually varies wildly from manufacturer to manufacturer, so 2 different manufacturers' 5W doesn't neccesarily perform the same.

(oh, also note that if you need 7.5, and you can't find it, you can't make it with a 50/50 mix of 10W and 5W- the mix is different, though I can't recall what the correct ratio is)

Indeed…just to confuse matters!
http://www.peterverdonedesigns.com/lowspeed.htm

(oh, also note that if you need 7.5, and you can't find it, you can't make it with a 50/50 mix of 10W and 5W- the mix is different, though I can't recall what the correct ratio is)

Though i should add…in terns of the cSt of a fluid (which is what you should go by, not the WT) then a 50/50 mix of fluids will give a cSt halfway inbetween.

In fact here is a mix chart for silkolene rsf…
http://www.peterverdonedesigns.com/files/Silkolene%20Mix%20Chart.pdf

And here is where my oil come from…
http://www.sportsbikeshop.co.uk/motorcycle_parts/content_cat/810
Quite cheap considering free delivery for 3 pots.

Anywhere cheaper for silkolene?