Words and photos by Lee Lau unless otherwise noted.

The result should be a light racing-oriented hardtail that can be ridden hard. Pictured here is D'arcy a Rocky engineer showing his confidence in the Vertex RSL on Kill Me Thrill Me, Whistler BC

Introduction

The new 2012 Rocky Mountain Vertex RSL hardtail frame weighs 997g (about 2.1 lbs) and is available 9.82 kg (21.6 lb) build in its top of the line configuration or as frame only. I really should stop right there as the weight is freakishly low for a bike that can be ridden off-road in any meaningful fashion and most people won't read further. But because I like to talk and because some people will be curious here are more details. Of note, RMB is only offering 29er hardtails as of the 2012 model year; 26" hardtail users will have to look elsewhere.

Carbon hardtails are nothing completely new but I would be remiss if I didn't point out some of the fanatical attention to detail Rocky put into designing this 2012 edition of their top of the line racer:
  • The weight is stunningly light but according to Rocky "we could have made it lighter"; incorporating a 142 x 12 rear end and internal cable routing added weight but added to stiffness, strength and aesthetics
  • Speaking of stiffness, the Vertex has massive down tubes, wide & flat top tube and a BB 92 bottom bracket.
  • Ride comfort was not ignored by providing minimalist thin seat stays to provide some rear end compliance
  • Some pretty fancy construction techniques (Smoothwall construction) was used to produce some unbelieveably thin and light carbon tubing.
  • Last but not least RMB's 29er geometry (they call it RTC 29) was targeted at "race geometry" that emphasized versatility in handling different terrain (although Rocky's literature seems to accent handling in technical terrain) namely; a short wheelbase and chain-stay length (ie a 29er that doesn't have the turning radius of a semi; shortened top tubes; 70.25 deg (yes Rocky is that picky - this is slack for a racing hardtail); less BB drop/slightly higher BB than previous Vertexes. Geometry charts are provided further on in the review so read on for more....
Video of the RM Vertex 29er in action




The 2012 Rocky Mountain Vertex RSL - available only in 29er



The Vertex uses a 142x12 rear end to maximize lateral stiffness



As well as the aesthetics of the clean frame (practically no bonding in this carbon frame - the only metal in the frame is a helicoil for the derailleur hanger and metal inserts for the water bottle mounts); the frame is so stiff there's no need for a seat stay bridge. This improves rear tire clearance to the point that you can put a 2.25" tire in the Vertex's rear end



A massive down tube and oversized wide top tube contributes to frame stiffness






Oversized BB92 bottom bracket and tapered headtube - again to add to stiffness



An extra wrapping of carbon around the BB shell and its bottom (not pictured) helps protect the frame



"SmoothWall" construction involves some proprietary (and hence confidential) processes that result in an incredibly thin and light carbon frame - as this cutaway shows. Apparently this process allows Rocky to have tremendous quality control not just over the carbon's exterior but also its interior as excess creases and detritus in the frame (eg resin, excess carbon) are minimized.






In terms of geometry, Rocky tried to match top tube length sizes (see above graph), and wheelbase and chain stay length vis-a-vis 29er and the 2011 26" RSL Vertex in the different frame sizes.





Geometry and specs for the 2012 Vertex RSL

MSRP and where to buy
ModelSizekglbUSDCAD
Vertex 990 RSL Frame18.5 (M)0.9972.19$1,899$1,899
Vertex 990 RSL18.5 (M)9.8221.60$5,549$5,649
Vertex 970 RSL18.5 (M)10.4122.90$3,849$3,999