Marin’s single pivot swingarm bikes have dominated the UK suspension bike scene, winning countless tests and awards since their introduction in the mid 90s. The suspension system was simple, easy to ride, light, versatile and with a single lifetime warrantied pivot and masses of mud room, they fared far better in the British climate than most linkage bikes.

Complete bikes were great value for the high level performance you got but after several sell-out seasons sales hit saturation point. The bikes were still great and still gradually evolving but everyone who wanted one had got one, and were just upgrading parts rather than getting whole new bikes.

What Marin / Whyte needed was a totally new suspension system to give their loyal supporters a reason to buy another bike and regain the clamouring customers of the “Mount Vision gold rush”. Abandoning the simplicity of a swingarm and switching to linkages is a huge gamble and reversal of their previous marketing mantra. Has it paid off?

NB: Before we go any further we’ll explain that most of this test centres round the performance of the rear suspension as we reckon that is the main development you’ll want to know about. The rest of the Preston features we’ve dealt with before, and the other kit is all proven favourites so details will only be mentioned where relevant.

Test Logbook

We’ve been riding hand made prototypes of all sorts of suspension designs since ATB Sales launched the Whyte bike two years ago, but we first met the current 4-bar layout at the start of this year.

Since then we’ve dragged it round Welsh forests that have ground the transmission into skipping and jamming swarf infested nightmares, and hammered it round our local woods and our favourite Nidderdale long haul loop, which seems to be in a particularly rocky mood these days.

What

Preston’s “Plus 4″fork was the first hint of Marin’s designer Jon Whyte moving in a linkage direction. Since then we’ve seen all manner of bizarre suspension systems lurking in his Cotswold workshop but while all of them have been smooth riding innovations acceptable aesthetics haven’t always been a strong point – if you’ve seen the Ripley clones in ‘Alien Resurrection’ you’ll get the general idea.

Thankfully the production linkage set up is the epitomy of discretion and half the people who’ve seen it haven’t even realised it’s not just a swingarm. Shock position and front half of the mainframe are in fact completely unchanged on either the Whyte or Marin bikes.

Where it all starts to change is with the front rocker linkage, a very short H linkage formed from two halves bolted together. This joins the front tip of the swingarm to the downtube just ahead of the big chainring point, but lower than the old single pivot mount.

The second compact ‘H’ linkage sits on the seat tube about two inches higher than the big ring. There’s also a big concave section in the seat tube to give room for the linkage arc to achieve full travel.

Rear of that is a conventional looking monocoque swingarm complete with torque tube cross-brace and stepped lower brace section. At the far end are either the bobbin locking “big gripper” dropouts of the Whyte or conventional dropouts on the Marin. The really good news is that you get proper disc brake mounts rather than bolt on extras.

The result of all this linkage action is a virtual pivot point that moves from a forward position to one just ahead and above the bottom bracket axle. This changes the suspension characteristics from that of a very long swingarm with a high shock leverage (1:3.15) to a shorter lower leverage (1:2.65) swingarm. This gives the shock a much more fluid response at the start of the stroke than at the end, helping to control bottom out despite a very plush initial feel.

Meanwhile, from a full extension position the axle path moves backwards more dramatically than a single pivot swingarm. It then gets to the sag point and rapidly flattens out, ending up in a zero chain growth position at full travel. In practical terms that means the wheel will move backwards and upwards over smaller bumps, but rely on the shock ratio change to control big hits. Pedalling force will also drag the wheel down into any compressions and undulations for maximum traction while bigger hits won’t be noticeable through the pedals.

The million dollar question

Graphs, arithmetic and projections are all very well but how well does it actually work?

The first riding impression is the almost complete lack of terrain feedback or bob through the pedals. Even cranking pretty hard up hill the rear end just sits motionless yet it’ll track over even the smallest rocks and irregularities for massive climbing traction. As a result it clocked up a couple of first ascents on severely technical climbs we’ve been attempting for years and cleaned other benchmark scrambles in a contemptuously surefooted fashion.

Once things get bigger and lumpier the bike takes a while to get used to, purely because it is so independent of your pedalling action. You can’t jack it up steps with a hard push like a high pivot bike, and you can’t squat it down and pop the front up like a low pivot bike. Learn to trust it though, and it’ll ride through, up, down or over stuff that’ll normally stop you dead.

The lack of feedback effectively extends that plush, floated feel suspension “mid range” through most of the compression stroke, with only a sharp ramp up at the end letting you know you’re maxed out. It also means no spitting of rocks in the granny ring, no wallowing through compressions when you’re cranking hard in the big ring and very little of the exaggerated rise and fall sensations that swingarm bikes give through the crests and troughs of undulating trails.

Flying down the far side it doesn’t take long to adapt to the bikes ability to pedal straight through the lines everyone else is skirting round or flat land hefty drops onto loose landing areas with total impunity. Just make sure you use plenty of tyre pressure as you often won’t even be aware of the rocks that are writing off your innertubes.

The combination of suspension isolation with power assisted negative travel make for masses of cornering traction, and the linear axle path means much less dive and disturbance under braking, letting you slide and power out of corners with no pick up lag. Short, broad linkages also keep tracking very tight through off camber or loose rock situations.

The only possible trouble we can see is that both linkages are very exposed to wheel spray, mud and all the other bearing-eating evils. Obviously time will tell, but the fact that all 8 bearings are the same lifetime warrantied units used on the swingarm bikes bodes very well.

Weight watchers will also be pleased to here that as the linkages support the swingarm in two places they can use thinner gauge aluminium which means the frame weight actually drops by 75g. the two support positions means it still gains stiffness though.

Up front the Whyte Plus 4s are unchanged except for the addition of a small rubber boot around the spherical bearing. For a full discussion of their plusses and minuses read this. In short it still tackles head on impacts with incredible fluidity compared to telescopic systems, and once you’re used to the steering geometry it tracks and turns with unsurpassed accuracy and traction. The downside is a tall ride position that not everyone likes and severe diving under braking or sudden body movements which make it a handful in slow speed technical situations or stand up climbs.

The happy news is that if you aren’t a fan of the Whyte forks then the Marin FRS bikes will use an identical quad rear end. We have to say though that the combination of the front and rear linkage systems gives a genuinely astonishing floated ride at high speeds, and it can be thrown into the dodgiest cornering situations at suicidal speeds and still come out upright and totally on track.

Rest of the bike

Our test bike was based around the existing Whyte XT bike spec, with Hope Mini upgrade. We junked the laughable innertube style Continental Twister tyre in favour of the latest Nokian rubber and the foam grips are already disntegrating, but the mix of SDG, Easton and Whyte own brand gear elsewhere is spot on. Complete bike weight (with pedals and a proper rear tyre) 27.7lbs.

Should I buy it?

With Santa Cruz bringing out the functionally similar VPP Blur, Klein with their monolink Palamino and Specialized with their Epic it’s way too early to come out with a definitive answer on this one. There some definite statements to be made though.What we can say is that the Marin will probably be by far the best value. Prices are predicted to be £100 more than current FRS models, which puts the complete 2003 East Peak bike level with a bare Blur frameset. Only the Epic is likely to compete.

More important for Marin and Whyte is that the Quad definitely pays them back handsomely for the risks they’ve taken. Don’t be put off by the very underplayed initial sensation as it’s more what the bike doesn’t do than what it does that makes it so impressive.

The brilliantly neat and unobtrusive design still keeps plenty of mud clearance, but it also irons out all the bugs inherent in the existing swingarm set up. Pedal feedback is all but gone except in the initial stages where it serves to add incredible climbing traction even with the comedy Continental tyres our bike arrived with. Middle ring fluidity is as good as ever but the stand out is that performance extends into big ring and granny ring as well as from sag point to bottom out. Add extremely accurate tracking and minimum brake jack for cornering poise and you have a whole new XC benchmark.

We’d still recommend the extra two inches of travel from Marin’s TARA swingarm bikes for bigger hitters, but the Quad will be loved by everyone from racers to epic multi day riders.

With uninterrupted power delivery, masive all round traction and succulent independent suspension in all gears, there’s no doubting that this missing link has bridged the gap from XC evolution to revolution.Now we just have to wait and see if the other manufacturers deliver on their promises.