A Beginner’s Guide to 29er Mountain Bike Categories. By: Writer Bob

My riding buddy has a Specialized Enduro and watching him cruise over the rough stuff gave me bike envy all last spring. With Significant Other budgetary negotiations complete, it was time to shop for a 29er (check out 29erOnline’s article on this topic – it convinced me). I like to think I’m reasonably bike savvy, having been riding with various degrees of seriousness since my teens. However, when I started shopping, it was clear I was out of touch with all the options and terms related to what type of bike I wanted.

First off, there are all the marketing terms that manufacturers and reviewers use to categorize bikes – Cross Country, Trail, All Mountain, Downhill/Freeride.. If I were going to ride across the country, I’d probably rather use a road bike of some sort. What kind of trails does a trail bike excel at – if you’re riding XC, you’re still riding a trail aren’t you? All Mountain sounds good, then you can ride the parts the other categories leave out, but can you ride where it’s flat? As for Free Ride/ Downhill, I like going downhill as much as the next guy. However, those guys in the Red Bull YouTube videos – that’s not down a hill, it’s off a cliff! They don’t need health insurance, they need pre-paid health-care plans.

Humor aside, what I found is that there are lots of measurements and technical information but not much description of what those different categories, measurements, and angles translate to on the bike. Sure, they eat up bumps, never flex, pedal great, and have state of the art tubing, but which type will I like best for my weekend rides? Is 130mm of shock travel overkill for me? Does 10mm really make that much difference? Should I worry about how steep the head tube is? It’s easy to get lost in the minutiae and hype when trying to get a feel as to what will work best and, ultimately, be the most fun to ride. Getting some saddle time may not solve much since, frequently, a test ride means tooling around the parking lot. Worse, you may be thinking you will have to order sight unseen because your local bike store does not stock many 29ers.

To try and find some answers, I started looking at web sites for a variety of types of bikes – some larger manufacturers and some smaller. Most use the same 4 categories and provide suspension travel information in addition to describing why their particular suspension solution and geometry are the best. I knew I wanted something that would smooth out the bumps more than my old ride, so I focused first on the amount of travel. Here’s a summary of what I found related to suspension on 29ers.

Cross Country – hard-tails with 100mm up front up to 100mm suspension front and rear

Trail – Full suspension with 100mm to 140mm travel front and rear

All Mountain – Full suspension 140mm to 160mm travel front and rear.

Free Ride/ Downhill Race – Full suspension 160 + mm front and rear. There are really not many 29ers in this category other than the Lenz PBJ(Lenz Sports has really been one of the pioneers of long travel 29ers other notables Intense and BCD).

These travel ranges really refer to 26ers. Look at the lower range of the travel for 29ers in each category.

The funny thing is, most of the manufacturers do not really describe what they mean – you’re just supposed to know, or maybe figure it from the information on suspension travel they provide (get your conversion calculator ready though because they can’t agree on inches or metric). Specialized has some decent descriptions if you happen to mouse over the chooser option – go straight for a bike and you are on your own though. Turner has the most informative approach – a simple graphic showing a series of rolling hills that grow steeper. It starts with Cross Country and Ends with Downhill. Cool, now we’re getting somewhere.

Small hills  = Cross Country,

Bigger hills = Trail,

Mountains = All Mountain

Ski lifts and Red Bull guys = Downhill

Since I doubt most readers see themselves hurtling down a mountain in body armor, I’ll set Downhill aside for the most part. So, it seems like we can agree on a continuum starting with XC and continuing up steeper and steeper hills to All Mountain  But wait, what if your small hills are really bumpy and your mountains are pretty smooth? Where I ride it’s pretty flat, but the washboard of roots is what got me interested in full suspension and some of the climbs and descents on the World Cup XC series look pretty steep. With this in mind, this XC to All Mountain continuum also probably needs to take into account the roughness of the terrain and how it will be ridden.

I imagine most readers live and ride somewhere between XC and Trail as far as hills and XC and All mountain as far as roughness of the terrain. Maybe that’s why Rocky Mountain divides things up even more into XC Marathon, XC Racing, XC Performance and XC Recreational. Wow, I guess that’s why people talk about having a “stable” of bikes if you need one for each purpose! Might be useful to some extent, but sounds like mostly marketing shorthand for different parts specs to me.

RMB also varies the travel between 100-120mm depending on the Marathon or XC, still as of now only applying to 26” bikes. For instance the Altitude29 is “trail/all-mountain”  but only has 115mm rear travel, confused yet!

Instead of describing the terrain, let’s flip it around and say what the bike will do

XC – light bikes including hard tales and full suspension bikes up to around 4 inches front and rear. The suspension is aimed at improving traction and taking the edge off the terrain enough to increase speed. Most of the time, the shocks are valved so that they lose small bump sensitivity in favor of crisp pedaling that at least feels more efficient. Overall then, when it comes to bumps, XC bikes tend to sacrifice comfort for speed and the ability to climb better (because its easier to lug a light bike up a hill than a heavy one).

Trail – more suspension travel allows you to feel the bumps less, but that added travel leads to heavier bikes and may mean the pedalling feels less efficient. Feeling the bumps less also means a less racy, less precise feel, but more confidence on technical sections or drops and more comfort over the long haul. You start using the word “plush” with trail bikes. If you can only have one bike, these are the ones that are sturdy, comfortable, and tuned to tackle most types of terrain reasonably well.

All Mountain – Bumps, what bumps? Let me at the rough stuff, especially when it involves going down! However, all that travel (or plushness) means there is a price to pay when going up the hills in terms of weight and pedalling efficiency.

So, hopefully, we have a handle on our categories as they relate to suspension. Next, Geometry. You know, hypotenuse, angles, stuff most of us have not thought about since high school. All the manufacturers have some kind of snazzy picture of their frames with all kinds of measurements, lines and probably lots of words saying why their particular lines and angles are better. Taken together these figures make up a bike’s geometry.

Niner stands out for an entire page dedicated to the special geometry of each bike, but they all have a graph and or picture with all the angles and tube lengths/measurements. Each bike will feel and fit differently based on these measurements. The end goal though is something that will accomplish whatever handling and fit parameters the designers are after. In terms of this discussion, what does geometry have to do with where a bike falls on our continuum? Does the geometry matter in what type of bike someone will want?

No one part of the geometry decides how a bike handles. Short chain stays contribute to making a bike handle more quickly by shortening the wheelbase. Top tube length, stem placement, and seat tube angle all impact where the rider’s center of gravity falls. How the designer juggles all these variables ultimately determines how a bike rides and performs. That said, one of the biggest factors, especially with regard to this categorization exercise, is head tube angle. On paper, the difference between 65 degrees (Downhill territory) and 71 (XC numbers) seems like a “so what.” If you are arguing over half a degree you are a very educated rider. For the rest of us, as you peer over the precipice of a steep descent, a few degrees could mean you are going to separate from your bike in an ungraceful manner. More likely though, 2 or 3 degrees will change how the bike feels to you.

There are certainly other considerations in terms of geometry, but head angle is the most obvious in terms of where a bike falls on the classification from XC moving towards All Mountain.

Most folks speak in terms of how slack the head tube is. The more slack, the smaller the number of degrees, and the more like a chopper motorcycle the bike looks. It’s not about cruiser attitude though, it’s about handling the bumps at high speed while headed down the hill. I’m pretty sure it all has to do with physics, but my high school physics teacher was fired mid semester and the chemistry teacher filled in, so I’ll take it on faith that the slacker angles allow the front shock and steering to work better when the focus is on handling rough terrain and downhills. Conversely, steeper angles move the front wheel closer to the rest of the frame and work with the other parts of the frame’s geometry to prioritize climbing and nimble steering in flatter, smoother terrain.

So, if XC bikes are about sacrificing comfort for speed and performance, it logically follows that XC bikes will tend towards steep head tubes (70 plus degrees) for quick handling. Heading towards the opposite end of the spectrum moves you towards the progressively slacker angles (64.5 degrees on the Lenz PBJ) that favor comfort and handling that will inspire confidence when headed downhill.

So, we’ve figured out what some of the marketing terms mean and dissected what goes into each category. That said, how does all this information translate into the type of bike you want to ride? How you ride and what type of rider you see yourself as is probably as important as where. Watch some of the Downhill races and you’ll realized that you might ride some of that stuff, you’d just do it much, much slower – those guys never seem to brake!

Based on the experience of folks at 29eronline, here are some generalizations that might be helpful. Please note that we are fully aware that stereotyping can get you in trouble – a talented rider can take a XC hard-tale off a 10 foot drop and a fast rider on an All mountain bike could whip an average rider on a super light, efficient XC bike. In the end, what type of bike you enjoy the most will probably have more to do with what type of rider you see yourself as.

Try these on for size:

XC rider = If he’s not racing now, he is hoping to in the future. He times his laps and is geared towards fitness and speed. He’s not just out for a ride, he’s training.

Trail Rider = A trail rider just gets on his bike and rides. He rides so he can drink a beer or 5 and eat some wings while he talks about his favorite rides with his riding buddies. Fitness is not the ultimate priority but definitely a motivating factor. The only reason he times a ride is so he knows how many miles he can do and not be late for the beer (after-party) or other family obligations.

All Mountain = An All Mountain rider is different from a Trail Rider because he is more of a risk taker (or lacks common sense, depending on your perspective). An All-Mountain rider looks for the most technically challenging natural obstacles to ride. He looks for opportunities to get airborne and pumps every divot in the trail. You have to be fit to ride this style but fitness is not the objective. Skill and conquering the trail is what it is about.

Downhill = It’s all about speed and taking it to the edge.

Hopefully, if you are trying to figure out where you fall on the off road spectrum and lost in the marketing, measurements and numbers, this will help a bit.

Writer Bob grew up near where Fat Bob and his tester crew ride, but currently does not live anywhere near 29erOnline’s not-so-secret lair. Therefore, his contributions to 29erOnline will be of a somewhat more grammatical and philosophical nature.

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