Giant XtC NRS line - To Travel or Not to Travel
Eric Layland Thursday, November 16, 2000
During the finals of our regional race series I was heading out on the third and final lap sitting in the lower half of the pack content to just spin through the last 6 mile loop. On my way up the initial climb, Doug our local Giant rep, cruised up beside me on an XTC NRS DS/1. We talked about the mutual pain we were feeling, our bikes and how they were handling the technical course. I was on my usual race rig, a Ti hardtail with lots of carbon fiber and XTR. I was more than a little surprised at the ease by which the Doug's XTC NRS was climbing. A quick gaze at the suspension and I realized there was zero suspension bob.
Mr. Giant is a solid rider but a confirmed roadie. I'm the mountain biker (XC and DH thank you very much)! But on the technical descents Mr. Giant would pull away each time. We hung together on the flats and were equal on the climbs. Then Mr. Giant took off on the final switchback laden decent to the finish and left me eating dust. HEY, a roadie can't do that to a mountain biker!
Hmmm... a full suspension ride that climbs like a hardtail, nimbly tackles tight singletrack and scorches downhills - with NO shock lock-out to mess with! Very interesting indeed. At the end of the race we talked more and Mr. Giant suggested I give the XTC a spin sometime. Always eager to check out another bike I happily obliged. But first, what is this "NRS" system all about?
The Problem...
Bike suspension cannot ignore rider induced forces. Most suspension gets set close to the frequency of the shock movements. The result is "resonance" which is a large movement initiated by little input. On a bike this is bad, or this is "bob" which is bad. Essentially the suspension design exaggerates your pedal strokes resulting in bob and robbing your energy. So Giant partnered with Renault Sports Formula One Racing - sorta like calling Batman. A good move on Giant's part based on Renault's tradition on the F1 race circuit.
A Giant Solution...
Goal: Isolate input of the rider's force from the terrain's input. Bump hits suspension and it's absorbed, you pedal and the suspension is extended. The secret to the NRS is two-fold. The four bar linkage geometry marries an extending suspension and a no-sag system. Like a see-saw, the linkage arms are arranged such that on one side the wheel pushes up to compress the spring; on the other side the rider pushes down trying to extend the spring.
The proper setting of the rear suspension is with no sag. Doing so allows the suspension to resist the rider's force yet absorb hits. The end result is bob-free climbing and hit absorbing suspension when you need it. A "Giant" atta boy to Renault!
On The Dirt
The following week an initial test ride would include a 1500 foot ascent up a 3-mile fire road climb followed by a blazing fast, rocky, root infested descent in wet conditions. Another 10 miles of Northwest singletrack was thrown in for good measure to give a solid overall test of the bike. With my DirtWorld team buddy Sparkling Lady in tow we took off up the fire road. Immediately the lack of suspension bob was noticed. Be it climbing in the saddle or hammering out full bore we were impressed. No bob means energy is transferred straight to the wheels and that makes you faster.
Whoopee! The technical descent was wicked fun. A high speed roller coaster section is easily railed. Wet roots which littered the trail are swallowed up by the NRS (No Resonance System) suspension allowing the assault to continue with no holding back. Two-foot drops are taken at speed allowing full use of the 3.75" of Rock Shox Dual Air SID rear. Once I got comfortable with the slightly different riding position, the bike induced "perma-grin" on my face.
Two things were immediately noticed. The particular bike tested had slight modifications (a different stem & a riser bar) which altered the feel a bit. Stock out of the box, the NRS offers classic XC race geometry. This isn't a common occurrence on bikes with 3.75" of rear suspension. Second the Rock Shox SID XC flexes significantly under the powerful stopping force of the Hayes hydraulic disc brakes. This takes some getting use to and honestly, it can't be good for the fork long-term.
Bottom line on the ride, the XTC NRS DS/1 is a stiff and snappy climber yet nimble on the singletrack. The rear suspension is active and responsive to small stutter bumps. Bigger hits that might throw you off your line if on a hardtail are easily swallowed up.
2000 NRS Component Package Highlights
Frame - Supersized Alcalyte SL CU92 & NRS suspension
Fork - Rock Shox SID XC, 80mm
Rear Shock - Rock Shox SID XC, 3.75" travel
Headset - Crane Creek ZS integrated, Ahead 1-1/8"
Cranks/Stem/Post - Race Face Prodigy
Drive Train - Shimano LX/XT mix
Brakes/Levers - Hayes hydraulic disc
Rims - Mavic X223, 32H>
Pedals - Time ATAC Alium clipless
Handlebar - Titec HellBent
Stem - Titec Lil Al, Forged alloy
What's In Store for 2001?
The design engineers at Giant were aware they had something good, but from feedback they knew improvements could be made. Most significantly in the 2001 design is a change in the angle of the rocker arm. The 2000 frame had a rising rate linkage as a result of the rocker arm being higher at the front of the linkage. For 2001 NRS has a falling rate linkage which stems from a linkage more parallel to the ground. The design modification will allow for a more plush ride because it will initiate sooner. Giant tells us that even though the rear will activate sooner, it will still continue to be an efficient climber.
A less significant change for 2001 is the way the rear shock is mounted. Instead of two wrap-around mounts on the seat tube, there is what Giant calls a "saddle mount." This design runs along the entire length of the shock on the seat tube and acts to spread the stresses over a larger area. Also worth noting is that the Air, NRS 1 & NRS 2 will have the new Mavic UST Tubeless 24H rims. The Air will also be Gucci-ed out with XTR & Hugi hubs.
For 2001 the new XTC NRS-Air will be the Cadillac of the line at $3,000. The NRS 1 will list for $2,000.00, the NRS 2 will set you back $1,500 and the NRS 3 will be comfortably priced at $1,100. The 2000 DS/1had an MSRP of $1850 while the DS/2 went for $1300. The XTC NRS line comes in 3 frame sizes; small (16.5"), medium (18.5") & large (20.5").
Who needs the XTC NRS line?
Someone looking for a race worthy XC ride and who's inclined to have fun on the ride up and the ride down.
Who should look elsewhere?
Retro minded riders who believe simpler is better.
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