Santa Cruz Blur XC Carbon
From the moment we got the media release, we wanted to get our hands on the Santa Cruz Blur XC Carbon. What a pleasant surprise to see such a slick full carbon rig come from a mother that had previously birthed nothing but aluminum. When we finally got word that one was headed our way, we couldn't wait to put it through its paces.
By the time it arrived, we already had a number of lingering questions in the back of our minds. Does Santa Cruz really need to build a carbon bike? Did Santa Cruz create a carbon version of their already popular and proven XC bike for the look, or did they create a whole new beast?Would the carbon version have a substantial advantage, or are they simply jumping onto the bandwagon? Would the durability, strength and stiffness stay on par with what we have come to expect from Santa Cruz? After the Inaugural Day press release in January, Santa Cruz delivered right on schedule just a couple months later. Our questions were about to be answered.
The day we received the frame we were blown away. We cracked open a few beers and stayed late into the night to build it up. We quickly realized this was much more than a full carbon frame. Out of the box, shock included, our large weighed 4.49 lbs. It's by far one of the lightest frames in its class, weighing less than the good 'ole Turner Nitrous, which for several years set the bar in ultra light XC performance. It's a full pound lighter than the previous edition Blur XC. But as you will see, we think this bike really deserves an entirely new name; the differences are just that great compared to the aluminum version. Our complete build weighed in at 23.5 lbs -- this using our XT bits left over from our last build. With a little effort, one could easily drop a couple pounds by simply swapping to a lighter wheelset, tires and Shimano XTR or SRAM X.0. We'd go so far as to speculate that the bike could be built up under 20 pounds if one really wanted to split hairs. But for us, we like to strike the balance between being light and durable. Having a sub-20 pound bike doesn't do you much good if you're left trailside with a broken handlebar or the like.
The build began at the full carbon headtube. We applied a thin layer of the included Syntace haftpaste to ease installation of a Chris King headset. The paste initially acts like a lubricant to help slide the cups in, but then uses micro particles to increase friction between the aluminum cups and carbon headtube. It also claims to decrease annoying creaks and corrosion. We have been using the Tacx version for almost three years in our shop, so we can back up the claims. There are two water bottle mounts, one on top and bottom of the downtube. The Blur XC Carbon also offers two options for rear brake and derailleur cable routing. The first is to run the cables along the downtube, beside the water bottle cage, then leap over the front derailleur before making contact with the seatstays. The second option, which we found more functional and aesthetically pleasing, is to go beneath the toptube. There are mounts for front and rear derailleur cables under the toptube, but nothing for the brake line so we stuck our own adhesive version near the shock mount -- it did the job just fine. The rear brake caliper mounts to carbon eyelets with co-molded aluminum inserts for added strength and security. The only other aluminum parts of the frame are the threads of the bottom bracket, rear derailleur hanger, and co-molded inserts for the linkage. Once built, you see nothing but unidirectional carbon. It's important to point out the difference between unidirectional and weave carbon. Aesthetically, unidirectional does not have the initial glamour of a weave, but because the fibers run just one direction, it is molded precisely as the engineers intended throughout the frame. Weave carbon may look cooler, but it is often just a top layer on top of unidirectional to create sex appeal. In this case, Santa Cruz set out to make the lightest and best performing XC bike. With that in mind they didn't add any unnecessary material simply for looks.
After a handful of endurance training rides, we hammered the Blur XC Carbon during a 60 mile marathon XC race through the Arkansas hills. With thousands of feet of climbing and descending, endless miles of rock gardens, river crossings, and 15 or so miles of gravel roads, we have considered it a thorough test. We immediately noticed the seamless transition of the rear suspension from fully active to nearly locked out. This was most noticeable when we quickly stood up to power over a rise or when the rock sections suddenly turned into smooth dirt. We don't attribute the perfect ride quality to just the shock or frame, rather it's a full package system of the Rock Shox Monarch 3.3 and new generation VPP design. The sag-dependent VPP uses a patented link enabling the rider to ride in a suspended "pocket" with both positive and negative travel available, whether pedaling or not. Santa Cruz alleges the new design limits chain growth by some 15-20% over the prior iteration of VPP. While this we were not able to confirm or deny this figure during our test period, we can attest to the fact that we never experienced any chain-induced feedback. The suspension's transition from plush to firm when hammering our of the saddle was as fluid as we've experienced.
At just 200 grams, the Monarch is the right tool for the job, allowing the Blur XC Carbon to yield 105mm of smooth, bob-free travel. Santa Cruz has dropped the travel by 10mm over the previous Blur XC (aluminum) in an effort to make a more efficient XC and endurance race bike. The initial setup of the shock didn't seem quite right -- according to our shock pump we were running around 225 psi to get the proper 25% sag for a 155 lb. test pilot. Meanwhile, the shock max is 275psi, and a 155lb rider shouldn't be anywhere close to maxing it out. Despite this, we made a game-time decision to race the bike anyway, and frankly we couldn't imagine it riding any better. But, the next week we made a few phone calls and uncovered the problem. From the factory the small needle inside the Schrader valve was threaded too far in, therefore our shock pump was not depressing the needle to let air into the shock. So the 225 psi reading on the gauge was really just measuring the air in the hose of the shock. We used a simple valve core removal tool to loosen the internal pin a few turns, and the shock acted perfect from that point on. We will be checking this moving forward on all frames we ship out, so rest assured you will not have to hassle with this simple, but otherwise unknown adjustment.
After the shock repair, the suspension had just the slightest bit of movement while seated on smooth singletrack, but as soon as the terrain got rough the Monarch seamlessly went fully active. It responded perfectly time after time, in one fluid movement. Sometimes the best designs are those you don't notice under you, that was definitely the case here. The Monarch was designed with a "Floodgate" to create a more efficient heart of this full suspension design. There are three lever positions to choose from -- open-gate, mid-gate, and closed-gate. We found ourselves riding mid-gate the majority of the time, as it really was the best all-rounder. On very technical descents and flat rock gardens we rode with the floodgate open and easily stayed seated while the rear tire kept contact with the ground throughout the pedal stroke. The only time we felt the need to fully close the gate was on pavement and gravel road climbs. This setting locks out the shock about 90% while seated, and thanks to the VPP linkage it feels completely locked out as soon as we stood up. Between the VPP design and a properly tuned shock, we were able to keep our hands on the bars where they belong, rather than flipping the lever on the shock over and over. As these damper and suspension designs continue to improve, lockouts will become obsolete -- it's just not necessary to adjust that frequently.
It is important to note that we found the best position for singletrack climbing was the mid-gate, not closed-gate, as one might expect. We could physically feel the rear wheel being pushed into the ground, while it climbed much better than a hardtail on uneven terrain. To keep the rear linkage moving smoothly, Santa Cruz includes an industrial grade grease gun and Super Lube which easily injects into the standard size Zerk inserts in the bottom bracket linkage. Unlike the Micro Zerk’s found on a Turner, our standard size gun fit snuggly around the eyelet for a very clean and quick process. With servicing this easy, you could do a quick spray at the local car wash (although it is not recommended), without worry of permanently forcing the grease from your pivots. How often you reload the grease is a byproduct of your riding conditions: we predict every six months in dry terrain, or every three in particularly muddy or wet conditions. No need to be intimidated here -- it's about as straightforward as putting air in your tire and takes about as long.
Continuing with the finer details, Santa Cruz securely molded each brake and derailleur stop directly into the frame -- nary a rivet to be found. This creates a much cleaner look and actually feels more secure than traditional rivets. The front derailleur cable stop, located behind the seat tube is slightly angled to give more direct cable routing and minimize friction. As the seat tube joins the bottom bracket shell it flares out into an oversized box shape, providing extra stiffness where your power meets the pedals. For testing purposes we did everything we could to get lateral flex, but switchback after switchback cornered like a monorail. Santa Cruz claims this is one of the stiffest, most flex resistant frames, period. We couldn't agree more. The Blur XC Carbon also uses two integrated protectors on the driveside chain stay. The first is a recessed chain slap protector; it uses a thick rubber pad contoured to the shape of the tube but and sits flush into the frame for a very clean a subtle look. For extra protection, Santa Cruz also includes the traditional Velcro neoprene sleeve, similar to a Lizard Skin. The second piece of assurance is a thick plastic guard attached to the chainstay just behind the chainrings. Again, it is recessed and contoured to the shape of the frame, this time to prevent the chain from jamming between the crankset and frame in the event of chainsuck. We never experienced any chainsuck, but it is likely to strike, on any bike, if the conditions are muddy enough.
We experienced no issues with the frame's durability, but for the skeptics Santa Cruz holds to a two year warranty on the frame, while the bearings are guaranteed for life. We set our expectations very high on this one, and apparently so did Santa Cruz. The Santa Cruz Blur XC Carbon is truly one of the finest bikes we have ever thrown a foot over. Whether you're in for a two hour XC race or riding solo at 24 hours of Moab, you can be confident that the Santa Cruz Blur XC Carbon is the right tool for the job.