Shimano’s WH-M785 XT 29er wheelset is reasonably stiff and reasonably priced at US$799/£468. The UST rims are a breeze to set up tubeless and, thanks to the use of cup and cone bearings, the hubs are very easy to service. Unfortunately, the WH-M785 also has some significant shortcomings that make it less appealing than many of its competitors.
The 29in version of the WH-M785 weighs 1,850g per pair (850g front, 1000g rear), which, while heavy, is 10g lighter than the previous model. The UST rim has an undrilled outer wall, so there’s no need to fuss with tubeless tape. This is accomplished by brazing threaded aluminum inserts onto the inner wall of the rims. According to a Shimano spokesperson, this arrangement allows the company to extrude thinner-walled rims.
Twenty four double-butted, straight-pull spokes connect each rim to the hub. Both hubs use tried and true cup and cone bearings, which makes bearing adjustments simple and – with a bit of preventive maintenance – should keep things spinning smoothly for many years.
Shimano’s Center Lock system is used to secure the rotors
The rear hub has a steel freehub with 36 points of engagement. The front hub takes a 15mm thru axle, yet the rear is only compatible with a 135mm quick-release; there is no option for a 142x12 rear axle.
On the trail, the WH-M785 wheels performed reasonably well. The weight was noticeable, as was stiffness. Tire squirm was an issue when running high volume (29x2.25in) tires, a result of the disappointingly narrow (19mm) inner rim width.
While the 26in version comes in Trail and Race versions, there's one 29er wheelset that splits the difference in terms of weight and features. In the process, the 29in WH-M785 makes significant compromises that limit its appeal.
The 19mm internal width is too narrow to adequately support high volume mountain bike tires at low pressures, and at 1,859g the wheelset is a bit portly for cross-country racing. Shedding weight or increasing the internal width of the rim by a few millimeters would have made it appealing to at least one group of riders.
The lack of 142x12 thru axle compatibility is disappointing
Last but not least, the lack of compatibility with 142x12 thru axles makes this set a no-go for many modern mountain bikes.
Offering Race and Trail versions in the 29in wheel size, along with making it compatible with 142x12 thru axles, would solve our issues with this well built but underperforming wheelset.