27 July 2009

bikefix Exclusive Review: Rocky Mountain Altitude 90 RSL

For 2009, the Altitude is a brand new Rock Mountain model with some unique features that are new to the industry. It replaces the aging ETSX in their model lineup and like the ETSX, Rocky are classifying the Altitude as a marathon bike. They don’t mention it as a “trail” bike but, that’s just semantics- the slacker geometry (when compared to the ETSX) and the 5.5 inches of suspension travel front and back put it firmly in the trail riding class. This is good because Rocky didn’t have a bike that fit this important category- The ETSX had geometry that was too steep for tough trail riding, and the Slayer was too heavy and not efficient enough pedaling-wise. Rocky Mountain knows that this category is an important segment and decided to start with an altogether new design.

One unique feature is the suspension. Just looking at the suspension design makes you think that Rocky licensed the 4-bar FSR Specialized patent, but if you look closely, you can see that the pivot on the chainstay is actually a tad higher than the rear axle. According to Rocky, the Spez patent only applies to pivots below the rear axle, and furthermore, Rocky has owned this design for years. In fact, it is the same type of suspension design that was used in the ETSX; they just took away the elevated chainstay design by moving the pivots down to just above the height of the rear axle.

The Altitude 90 RSL is at the top of the 5-model Altitude range at close to $6,500.00, but those at cheaper price points all share the same suspension and geometry. The 90 RSL and the 70 RSL are the only carbon fiber models though, and although I haven’t ridden an aluminum model, I’d imagine the carbon makes a difference in the way the bike rides. I’m not going to spend a lot of time going over the kit. If you need specifics you can go to the Rocky Mountain website at www.bikes.com. Suffice it to say that Rocky went all-out on the 90’ RSLs spec with Mavic Crossmax SLR wheels, Formula R1 brakes, and a bunch of carbon fiber bits from Race Face. The one thing I will mention is the bad choice of tires that came on the bike: the Hutchinson Python UST 2.3. Sure, the python is a fast rolling tread, but the 2.3 UST is a fairly heavy tire by today’s standards. These tires don’t make the bike feel fast at all- a disappointment when spending this much money and having that sexy carbon fiber frame. I changed the tires to Schwalbe's Racing Ralph UST 2.25’s after one ride and that made all the difference, but have to mention that it was a poor choice to mount 850 gram tires to some of the lightest [true] UST wheels available. There are a number of 2.1 – 2.2 UST tires available now in the 680 – 780 gram range, and let’s face it: 2.3 Pythons are more like most companies' 2.2’s.

The other unique feature of the Altitude compared to other bikes available is the super-steep seat-tube geometry which Rocky call “straight up” geometry. At 76˚ it is 2˚-3˚ steeper than most bikes out there. The idea behind this is that on the uphills most of us scoot forward on the seat to aid in steering while keeping weight on the suspension so that traction doesn’t go out the window. The steeper geometry of the seat-tube moves the seat forward on the bike and essentially means you won’t have to “scoot” forward as early of as much. Meanwhile, on steep downhills, riders are trying to get their weight behind the seat so they don’t go flying over the bars. Again, since the Rocky geometry puts the saddle further forward, it is easier to get behind the saddle in the steeps. So that is the idea. When I read about this design I was intrigued, but I had concerns about how it would feel over flat(ish) ground at medium to high speeds. My worry was that cruising along at a good pace I would enter a technical section or hit a large bump, and being more forward on the bike than usual, it might launch me over the bars.

After riding this bike quite a bit, and even racing it in a particularly grueling race with lots of climbing and lots of descending I have decided that the Altitude rides very well. I think that Rocky Mountain have pretty much succeeded with their unique geometry. The bike climbs great and the forward seating is noticeable and effective, but not so much different that it feels weird. It works downhill too: it is easy to get behind the saddle and the 69˚ head angle keeps the steering from being too fast on the rough stuff. My fears about high speed flats and rollers were noticed but not realized. It is possible to get caught off guard with my weight too far forward but I have yet to have an accident from this and the more I ride the bike, the better I get, and the issue all but goes away.

Having ridden the Altitude, I can see why Rocky was reluctant to but the “trailbike” name on this frame: It encourages the rider to attack the hills and pedal hard. The frame is incredibly stiff and my 195lbs. can’t noticeably flex it. Too be fair to Rocky, this is an ideal marathon bike but it also doubles as a great trail bike. The descending is equally competent and very controlled. I have surprised myself with how well this bike does everything. That said, it’s not as plush as other trail bikes on the small and medium bumps. Not that it’s bad, just not as smooth, and I ride mine with 50% sag down to about 30% sag. It makes up for its lack of small-bump sensitivity with insane climbing efficiency though, and racer types that are thinking about full suspension, or more suspension travel, will do well to ride an Altitude before making up your mind on something else.

The carbon fiber frame is stiff as can be, and the cosmetic weave is good looking but the frame must have been designed for stiffness before weight, because this frame is not as light as some others offered out there (including some aluminum ones).I didn’t weigh it as a frame but with almost an identical build to my Maverick Durance it weighed in right at 25.9 lbs. which is just a bit heavier than what my Durance weighs. It is still light mind you, but for this money I’d expect a bit less weight- especially from a carbon frame. Being a big guy though, the stiffness is also very important to me, so in my eyes it’s probably a wash, but many riders are going to consider this an issue.

The biggest issue beside my rant about the Altitude's tires has been its pivot bolts: they keep coming loose. That's not a big deal if you are aware of it but still… Loctite has not even completely solved the problem. There are a number of people concerned about the looks of the bike- with the severe bend in the downtube occurring well forward of the bottom bracket. Looks are subjective though so I’ll leave that to the buyer. Some people have mentioned that this curve actually hinders riding and that you can impact the frame while riding. Internet photos show a stationary bike placed with a log in just the right place where the frame will hit before the chainrings, but this is just not a real world situation. I suppose it’s possible if you screw-up an attempt to ride over a big log, but other than that I can’t imagine how you would do this while moving forward.

This bike is a huge step forward for Rocky. It does everything well and leaves little to complain about. The rear shock is fairly linear (which I like) but the suspension design seems err towards riding efficiency over suppleness. I don’t plan on selling this bike soon, and on many trails it is definitely the fastest full-suspension bike in my stable.




Faceless Ghost said...

So, if you were heading out for five hours or more of epic singletrack, would you take your Rocky Mountain Altitude or your Giant Trance X? How about if you were competing in an ultra-endurance race?

The Bikeworks Crew said...

He would take out his Maverick Durance, of course.

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