Thursday, January 16, 2014

Sarto Tenax 650b Complete Bike Review at - Part II

Part II - The Builds

Hoops n' hubs - Chary and I were slated to test the two Tenax frames in production for us in Italy and we knew this would soon turn into a clandestine competition of gram shaving. We were in agreeance that we'd both go with our faithful standby, Stan's Notubes ZTR Crest 650b rims and DT Swiss 240s hubs (15mm front and 12x142mm axle rear). I knew he'd have something up his sleeve to try and beat me in this upcoming full fledged war of weight savings, therefore I snuck an order through for some DT Swiss Aerolite spokes. Hey, call it a mulligan due to my disadvantaged goofy large sized frame!

Without question we planned to outfit these capable Italian racing steeds with Formula's R1 Racing Brakes and their ThirtyThree 27.5 100mm travel forks, Chary and I were left scratching our heads with the drivetrain choices. Simplicity and a quiet drivetrain were at the forefront of my mind, meanwhile my colleague wanted to try something new, new and very light in weight.

I have long missed those days of riding my ol' silent singlespeed downhill accompanied only by the sound of the dirt being compressed beneath my tires and the chatter of my own teeth. Additionally, being that I was in love with the classic lines of the Sarto, I didn't want to complicate the build with extra cables and gears. Sram's XX1 1x11 setup with their roller bearing clutch Horizon rear derailleur was my choice, although I thought I might mix it up a little. The 10-42 X-Dome cassette is no doubt innovative and a machining masterpiece, but I much prefer the thought of turning over a larger front chainring to maintain higher speeds / wattage rather than shifting into higher (smaller) gears down the cassette. Sure, call me a cross-chainer.. I'm guilty! Knowing that I'd be stuck pushing some hard gears up some steep grades due to the lack of a 42t cassette, I opted for Rotor's QX-1 chainring and the largest 11-speed cassette I could acquire from SRAM, the WiFLi 11-32t. The macho man within me figured I could handle a 36t QX1 chainring, however the realist inside of me (and not to mention my tempermental knee) figured I might end up needing Rotor's 34t QX1 gear. Regardless, I'd build it with the 36t for initial bragging rights and also to ensure the initial chain cut would provide for enough chain slack.

Chary, always striving to be different and knowing he'd need to rely on a truly light weight double chainring setup (due his fondness of the granny gear), selected the German manufacturer Acros with their A-GE hydraulic shifting group. Acros' A-GE system provides for a fantastic friction-free shifting experience that allows for an uber consistent and maintenance free shifting experience. Without the need for heavy steel return springs, shift cables, and steel wound cable housings, Acros is able to achieve a sub 500 gram total weight. Outfitting his Tenax frame with a Rotor 3D+ mountain crankset and matching Q-Rings required alittle fabrication and an adittional 10grams of weight for the Acros A-GE front derailleur to cooperate. Regardless of that, setup was accomplished without a hitch.

With the help of New Ultimate cockpits and Fizik saddles, we were ready to hit the scales...before weighing down these bodacious bikes with dirt and dust.

Wilier Triestina Zero.7 Shimano Dura Ace 9070 Di2 Comina Aero MCC Complete Bike

More details on the Wilier Triesitna Zero.7 frameset.

Sunday, January 5, 2014

Sarto Tenax 650b Complete Bike Review at

Part I - Love at First Sight

Love at first sight - that's precisely what Sarto did for me with their Ampezzo, now called the Tenax for 2014. Even before learning that Sarto united 100mm of full suspension travel with a pair of 650b wheels, I was first drawn to this bike because of its revitalizing classic horst-link design. These days you find mountain bike manufacturers having to resort to odd tube junctions and pivots to accommodate the suspension design they decided to utilize (i.e. DW-link, Virtual Pivot Point, single pivot, four-bar / horst link, etc.). Sarto's aim with this full suspension world cup design was to simply allow the rider to excel everywhere - to be able to attack the descents without falter all while being able to climb untethered. Oh, and don't forget about this bike's roots - Sarto is designed and hand made in Italy, therefore the Tenax must weigh little and be attractive at the same time. With their performance and good looks requirements laid out before them, Sarto had but only one suspension design in mind to get the job done.

Through the years I was always captivated by Dave Turner's first generation of frames using Horst Leitner's improved four-bar design mated to a seat tube based rocker pivot. While appearing quite simple and not too eye catching alongside other designs at the time, the 'Horst Link' came down to being a simple yet very effective design. It allowed for unhindered independent rear suspension functionality that combated unwanted suspension compression during braking (brake jack) and pedaling force (pedal bob). Critics of the four-bar / Horst link design have always accused it of not reducing pedal bob enough. Through the years suspension manufacturers have been able to perfect the Horst link design by producing shocks that can counteract the power-sapping suspension tendency without impeding full suspension travel when needed. However, here in the U.S. the Horst link design has always been plagued by patent law and politics due to one of the largest bike manufacturers acquiring several of Leitner's patents in the late 90's. Fortunately, patents have expirations and we shall now have access to some previously intangible European gemstones.

I always thought the perfect mountain bike formula has always been inevitable as it was just a matter of time for the convergence of three special ingredients. First, Sarto, a bike company known for hand tailoring some of the best quality bike frames out of Italy and now with their new full suspension cross country mountain bike mission. Second, we have the most proven rear suspension mountain bike suspension design now liberated from one-brand penitentiary. The third ingredient, icing on top to complete one very sweet cake, the utilization of the 27.5" or 650b wheel dimension. Hallelujah! Time to order a couple of frames and start brainstorming some builds.


More details on the Sarto Tenix 650b frameset.