In a big jump to big wheels, Marin’s Rift Zone XC7 is the flagship of their two 29er, one 26er fast bike range. Fast rolling 29in wheels, supple suspension and attentive handling angles all make it a comfortable and friendly place to spend a day cruising, swooping, sweeping singletrack or open moors. High weight and low overall stiffness mean there are better choices for those who want to push the pace on the climbs and more technical trails, though.
Ride & handling: Fast and smooth, but weight is high and stiffness low
The easy, enthusiastic start to the XC7's short suspension stroke combines with the big wheels for a super-plush, momentum-nurturing ride over smaller bumps. The Fox dampers are as smooth and controlled as usual and a progressive end to the stroke means you’re never wallowing about deeper in the travel than you should be.
This all means you’ll rarely feel the need to leave the saddle, letting you keep putting the power down smoothly as long as you’ve got crank clearance. The relatively aggressive head angle designed to mimic smaller wheeled bike handling suits seated piloting too. There’s no worry about steering all over the shop on seated climbs and it turns the front wheel in quickly rather than needing some shoulder behind it or a counter steer swing to convince it.
The XC7's fast rolling, round carcass Continental tyres are quick rolling enough to offset some of the bike's 14.2kg (31.3lb) mass when accelerating. The long tyre contact patch and increased momentum of the bigger wheels also helps flatters the hard compound for significantly more dry/intermediate grip than you'd expect from the 26in version of the same tyre.
The chain-pull-reactive Quad Link 3.0 suspension gives useful grip or slip feedback through the soles of your feet, letting you tune your torque instinctively to the available adhesion. This all creates a very smooth and efficient cruiser for ironing out rough trails and reducing fatigue, but it’s not so convincing when you start to push the pace.
For a start, the high overall weight cuts into acceleration enthusiasm dramatically when compared to other similarly priced 100mm full-suspension 29ers we’ve ridden that are several pounds lighter. The offset lower linkage also means significant flex during the driveside crank push and a rhythmic rubber chain sensation when you’re trying to heave the bike up to speed.
While there’s plenty of traction feedback the stiffening of the suspension under power also makes it more prone to spit its drive dummy if you get forward over the bars on steep, loose sections. The progressive action of the rear shock means a fair old wallop when you come off bigger stuff too, although the bigger wheel format still adds extra cushioning compared to a 26in wheel.
The low spoke count wheels, quick-release axled fork and frame all add palpable pliability into the mix. This flex is comfy and potentially grip flattering when you’re casually cruising or letting the bike flow tai chi style. Start to get pushy in the corners though and you can really feel the twist between you and the trail.
Add the plasticky low tread tyres and line choice is definitely approximate rather than accurate, though the Marin will generally get to the other side somehow if you let it find its own way. It’s got a habit of bending the front wheel underneath you if you go for the brakes on sharper descents too, confirming that it’s a true cross-country bike, not a short-travel technical trail bike.
Frame & equipment: Good spec but chassis is flexy and outgunned on weight
Not only is the idea of a 29er full suspension bike new to Marin, but they've also switched to a new suspension system for 2012. This means there’s a lot to talk about with the frameset. The short tapered head tube keeps the front end low, while the curved down tube and sloping top tube share an extended weld seam.
The top tube kinks below the nose of the saddle to give reasonable standover clearance despite the big wheels, and a curved seat tube tucks the rear wheel and rear subframe in relatively tight. The short Quad Link 3.0 lower block linkage is offset significantly to the offside and the driveside chainstay is deeply bent for chain clearance. The new suspension system means room for a conventional bottle mount.
Slightly tortuous tube routing leaves adequate tyre room and all the linkage bearings come with a lifetime warranty (ie. replacement is free if they wear out). A claimed frame weight of 3kg (6.6lb) puts the XC7 on par with boutique 100mm 29er frames such as the Santa Cruz Tallboy, but it’s significantly heavier than 29er full-suspension frames from Giant and Scott.
While the cheaper (£1,799) XC6 29er sits on RockShox dampers the XC7 gets a basic Fox shock and fork with rebound adjust and lockout on both ends. The tapered steerer helps keep things tight up top, although the quick-release rather than 15mm screw-through axle tips are obvious in the ride.
The 28-spoke Black Flag Expert wheels are pretty flexy, but they’re tubeless compatible if you can persuade the porous Continental tyres to stay up with sealant alone. Their shallow tread and hard compound is obviously designed with long, fast summer rides in mind rather than traction testing technical skirmishes on wet season singletrack. Luckily, the Formula RX brakes let you nurse what traction you have got when things get damp and dicey.
The Shimano transmission is tough as nails and delivers a full 30-speed gear spread through smooth and weatherproof shifters. While 3x10 adds weight compared to 2x10 the 36-tooth large cassette and 24t inner ring let you winch up almost anything. Marin’s cockpit gear is well shaped and topped with a custom colour saddle for very tidy looks.
This article was originally published in What Mountain Bike magazine, available on Apple Newsstand and Zinio.
