The production Mount Vision 5.9 will have a slightly different paintjob and parts to the bike featured here but the frame, which is shared across the whole platform, and suspension fork are 2010 spec. Updated 3D forged and CNC-machined links are now curved for greater stiffness and to offer better access to the shock controls. Front-end stiffness is also boosted by an oversized head tube, which runs a Zero Stack headset. The head tube is shorter to allow a lower bar height when competing, although for trail use we ran it exclusively with all the spacers under the stem. The modular dropouts can be upgraded to a Maxle and all Mount Visions have line guides should you want to use a height adjustable seatpost. Our pre-production bike weighed 27.75lb but 5.9s off the assembly line should be 25lb.
The Marin is probably one of the stiffest 120mm bikes we’ve ridden — it is rock solid on the climbs and never put a foot wrong on hard banked turns or cross-rutting double track. It’s efficient pedalling in all three-chainrings and easily distances the ST4 riding tempo on fire roads or carving uphill hairpins like on White’s Level. Marin has tweaked the geometry since the last time we tested this bike — the head angle is a degree slacker at 68.8deg but it’s still slightly steeper than the Orange and this is noticeable when descending. The difference is actually more pronounced because the Marin has a shorter wheelbase, although we’ve been told production 5.9s will be 5mm longer. The 5.9 has a slightly higher bottom bracket than the ST4 so should feel less stable but we found the frame stiffness gives the bike a direct connection with the trail. Marin measures the geometry with a 2.1in Maxxis High Roller tyre fitted, which has a lower profile than the CrossMark. This equates to around 3mm but we do think Marin could go lower (and longer) without sacrificing pedal clearance.
The frame layout and swingarm design means the 5.9 has a higher centre of gravity than the Orange, and while it turns easily into corners, it’s less lively, requiring more effort to manoeuvre. We also found the 5.9 tended to sit up and ramp up at the end of its travel. Plus it never felt like we were getting the 120mm of wheel travel despite the O-ring being at the end of the shock. It turned out the bike should come with a Fox Float RP23 with 175psi in the boost valve, not 225psi; so no wonder it ramped up.
We’ve ridden a replacement with the lower BV pressure and it’s much better, but we can’t help thinking that Marin hasn’t realised the full potential of the Quad system — it could offset some of the pedalling and big-hit capability for a more even feel to the suspension.
Compared to the Orange ST4 the Marin 5.9 is the more efficient, stiffer, better made bike and it didn’t have any issues with chainsuck. The only thing is — the Marin 5.9 just isn’t as much fun as the Orange ST4. We can ride it blisteringly fast, but at the end of the day it lacks that bit of character to make us really want one.
Mbr rating: 8