The first thing we noticed about the Marathon Race fork was the new 'Marathon' name, which marketeers obviously believe to be sexier than 'XC'.
We fitted the Marathon Race to a test bike (replacing a Fox 80X Terralogic unit - a pure race XC fork and a tough act to follow), and noticed something else: the weight. At a fraction over 1.5kg, with untrimmed steerer and remote switch, the Marathon Race isn't the lightest fork on the market but then Marzocchi have never played the diet game... On this occasion they have produced a tidy onepiece alloy crown/steerer assembly with chunky magnesium sliders. With progressively stronger disc brakes used on a good proportion of rigs, the reduction in fore/aft 'flutter' under braking is welcome, and we found the fork to be reassuringly stiff in all conditions.
Marzocchi use both positive and negative air chambers to balance the action of the fork, as well as a separate air chamber control for the firmness of the fork at the end of the compression stroke - aka Progressive Air Resistance. Increasing the PAR reduces the chance of bottoming but also slightly reduces overall travel. This is useful, just use it sparingly. You also get a rebound adjuster - we ran ours three clicks from full slow (this stops the fork from popping back too fast but doesn't pack it down for repeat hits). All these tuning elements are probably enough for most riders, but then Marzocchi have also thrown in TST (Terrain Selection Technology). The dial at the top of the right-hand leg allows you to tailor the fork's damping characteristics; from full lockout (which can be activated by an optional remote barmounted lockout switch), through All-Mountain (AM), to a pure Downhill (DH) setting. As a rule, most riders will probably find the setting they like best and leave it there (we did), with only occasional use of the lock-out facility.
Out on the trails, the initial weight concerns of the Marathon Race are soon forgotten: it's an excellent performer. We ran V-brakes but never suffered from brake rub (even with the pads adjusted close and rider in full ape climbing mode). The fork seems to get better with every mile too, and if general Marzocchi history is anything to go by, it'll still be still going smoothly in 1,000 miles' time.
With so many variables available, the fork does take a while to set up. Many racers will probably just pump it up hard and go, which is a shame... because a bit of tinkering will get a great deal more performance out of this 80mm fork. There's no getting away from the fact that this is a fiddly fork to tune, but if you're willing to put the effort in, you'll get a whole lot more than you bargained for.