Shimano have produced a range of good value and well made wheelsets for a few years, but for 2013 this neat set of hoops has all the features of the higher end models, albeit with cheaper materials and finishes. Two wheelsets are available, the skinnier cross country orientated MT-66s and these MT-68, which are focused toward the trail/all mountain segment. [private]
Out of the box our first impressions are excellent, with nice decals and trendy white rims on black spokes. All Shimano wheels are hand-built, and you can really tell with perfectly true rims and even spoke tension. Value for money is high, as there is a (arguably best in the business) Shimano quick release skewers included, and the tubeless ready rims have tape and valve already installed. This is a major bonus, especially at this pricepoint as all you need are tubeless ready tyres and some latex sealant to convert to tubeless. The tyres were reasonably easy to fit; the rear sealed up using only a track pump although the front required a trip to borrow the local servo compressor to finally get seated. The rims are good quality, non-eyletted and come in a reasonable 21mm width, ensuring the large volume tyres fitted showed a good profile without threatening to roll off the rim, even at low pressures (for reference, 2.5” Schwalbe Hans Dampf on the front and 2.3” Nobby Nic out back).
The front wheel is 15mm bolt through only, whereas the rear has QR or 12mm options. Hubs are Shimano branded, with a non-flashy, but functional finish. The wheels use butted straight pull spokes, as this avoids the J bend point of weakness. The whole wheelset is user serviceable; a nice touch is the included spoke grabber is provided so you can true the wheel without the spoke rotating.
The bearings are of the loose ball and cup and cone variety, which from an engineering viewpoint are more efficient than cartridge, and shows the manufacturing muscle of Shimano, as the bearing races are more involved to fabricate (cartridge bearings are easily fitted to CNC’d hubs, which is why smaller companies use them) and are highly user serviceable. The bearings stayed tight over the course of the test period, but prior experience with Shimano hubs suggest that the cones will need adjustment in the future. Disc rotors are fitted via the centerlock mechanism, although adaptors are available should you wish to run 6-bolt. The matching SLX level discs are well made and worthwhile however it should be noted that the front 15mm axle requires a different, larger diameter lockring than the one provided to get over the bigger axle.
For the first ride on the wheels was at the playground that is the You-Yangs in VIC. This spot combines rocky technical downhills with fast, flowing singletrack, an environment that favours fast accelerating and tough wheels, and to which the MT-68’s were well suited. One of the design points of the rear freehub is its fast pick up, and the non-intrusive whizzy ratchet sound, which is different to previous years silent clutch mechanism. This rapid pick up was excellent when accelerating out of corners and also when climbing out of the saddle through technical sections. In spite of their 24 spoke build, no discernable flex was a detectable over the range of situations found on a good ride; through berms, off drops, under heavy braking, stomping on the pedals on technical climbs. The front wheel tracked superbly, with little or no hint of flex. Just to check, they were used on a shuttle day, and they remained true, and the spokes tight, even after two days of repeated downhill runs.
The performance of these wheels was an eye opener. The hoops they replaced were at least twice as expensive, with no discernable difference in performance. [/private]