A Basic Guide To The Purchase of A Mountain Bike

Conor Watkins' Ozark Mountain Experience
Articles 37&38 Combined

Basic Guide To The Purchase of A Mountain Bike

Picture of the Adam Britt Mountain Bike Race held on the Kaintuck Trail near Newburg, MO.
This picture shows competitive riders on their mountain bikes.

Although there are various types of bikes on the market today, the mountain bike is by far my favorite. I do not like the ride of a road bike as well am rough on my bikes, so I require a bike that will withstand the rigors of hard off road use. The mountain bike, in a simple description, consists of a rugged heavy-duty frame, knobby tires for traction in off road use, gears to provide comfortable pedaling at various speeds/inclines, and upright handlebars. Options to consider when selecting and purchasing a mountain bike are discussed here.

Mountain biking can be an excellent way to exercise and/or release stress while seeing in the outdoors. The mountain bike is almost a necessity when riding the roads around Rolla. The thin tires of a road bike go flat easily when ridden over potholes and other rough spots so common to both gravel and paved roads in the Ozarks.

Before going mountain biking, one either needs to rent or own such a bike. If new to the sport of mountain biking, it may be a good idea to rent different brands/models in order to experience different bikes. Although renting is expensive, it is a better alternative than buying a bike that doesn’t fit the rider well. A decent beginner mountain bike will sell for $250-$350. Higher end models can sell for many thousands of dollars.

Although models sold at discount stores as “mountain bikes” are generally cheaper than models bought at specialty bike store, the serious rider should avoid them. Their quality is much less than that of a real mountain bike. Some of these “off road” bikes are not really meant for all terrain use. When reading the fine print on the tubing or the manual, it sometimes will say “Meant For On-Road Use Only” or something similar even when marketed as a mountain bike. These bikes are generally made of lower quality components and materials, which makes for a less pleasurable riding experience, even if the bike is only to be used on paved roads. Cheaper, heavier, and weaker steal is used in the frames. More of this heavier steel is used in order to attain a necessary strength, making the bike extremely heavy. Moving parts, such as derailleurs, are not designed as well or machined to as exact specifications as those on regular bikes. This can lead to problems with shifting gears, mechanical noises, and other problems when riding. Some of these bikes are so cheaply made that they only last about one year if the use is lucky. It seems like a better idea to spend a little bit more to buy a bike that is more enjoyable to ride and will last for many years.

A rear derailleur is shown here.
Quality derailleurs and other mechanical parts are essential
to a quality riding experience and the absence of noises during
use.

When looking to buy a mountain bike, these are several factors that any buyer should consider. One of the most advertised features of a bike is the material used to make the frame. Options include carbon steel, Cro-Mo alloy steel, aluminum, titanium, and carbon fiber. Carbon steel is the least expensive type of material but it is very heavy and will rust. Riding such a bike is not fun as they are heavy and generally cheap bikes of a poor overall make. Cro-Mo steel is an alloy of steel with chrome and molybdenum, which makes it lightweight and strong. Although it is generally found on today’s low-end bikes, it is not necessarily a bad choice. Cro-Mo steel will rust but forms a self-arresting patina (coating) and will take many years to rust through. It is also very durable and will take the abuse of hard riding without fatiguing. Aluminum is becoming more common as it becomes a less expensive option. It is lighter than Cro-Mo steel and doesn’t rust. One downfall to aluminum frames is that they are generally stiffer than steel and don’t absorb bumps as well, but suspension can take care of this. Aluminum is also more subject to metal fatigue but this is not much of a concern as it takes years to fatigue a frame and most carry a lifetime warranty. There are various different types of aluminum alloys used in bike frames but those are not discussed here. A general rule of thumbs is the lighter the alloy, the more expensive the bike. Lightweight titanium alloys and even carbon fiber are also used to make the frames of some bikes, but these are very expensive, and thus rare. Professional riders such as Lance Armstrong ride bikes made of these materials as do serious enthusiasts. They will not be discussed here, as those looking to buy such bikes should not need to read this simple article.

The size of the frame is also important depending on the size of the rider. Frames are generally measured based on the height of the tube below the seat post. Since the frame is essentially a right triangle, the length of this tube affects the length of the other tubes. Make sure to be fitted correctly to the right size bike when testing a bike. A rider with longer legs and arms will want a larger sized frame. As with clothing and shoe sizes, frame measurements and geometries do vary from manufacturer to manufacturer, so make sure to test ride any bike considered for purchase. Bike manufacturers are following in the footsteps of clothing and shoe manufacturers by offering men's and women's models. Women's models tend to be slightly lighter and more ergonomically friendly to the female rider.

Today’s mountain bikes offer different suspension packages. Some bikes come with no suspension, but these are becoming rarer. Most seem to offer front suspension and some offer full (both front and rear) suspension. Front suspension is definitely worth having and standard on most bikes. Full suspension can offer greater comfort and control when riding on rough terrain. Bikes with only front suspension are called hard tails. Front suspension is built into the front fork while full suspension is partially built into the bike frame itself. Although full suspension is more expensive, it is still affordable to most riders who really want the option. As with other components, suspension systems vary in quality, performance, and cost.

Bikes with only front suspension are called hard tails.

Some bikes offer both front and rear (full) suspension. The rear shock is usually
built into the frame while the front shock is built into the fork.

Picture showing a rear shock on a full suspension bike.

Front shocks are usually built into the front fork.

It is also important to pay attention to the components on a bike such as the wheels, derailleurs, braking system, seat, tires, and others. Wheels come in steel and various types of aluminum alloys. Insist on getting aluminum as it is lighter. Although there are derailleurs made by many manufacturers, Shimano is by far the most common. Shimano makes derailleurs of various grades, ranging from dirt-cheap to top of the line. The front and rear gear cogs, known as the chain rings and the cassette, respectively, also vary in the type of material and design used. The number of speeds a bike has is dependent upon the number of gear cogs in the front and back drive train components. Bikes made today generally range from 21 to 27 speeds. Although some want the most speeds available, a good low gear and high gear are most important. A very low gear provides the torque needed to climb a steep hill while a good high gear provides speed on smooth flat roads. Seats also vary in style and are one of the most important parts of a bike as far as comfort is concerned. It seems that the most lightweight performance oriented seats are often the least comfortable. A good seat is necessary for an enjoyable ride. If wanting to upgrade a certain component, some bike stores will allow its changing for an increased purchase cost. Bikes are much like computers in that most parts can always be replaced with better components in the future.

Tire choice is important depending on the intended use for the bike. A bike intended for off road use should have knobby tires to provide traction in mud, leaves, etc., while a bike ridden around town should use smoother tires for an easier ride. Smooth or slick tires provide much less vibration and rolling resistance but are not suitable for off road uses. There are hybrid tires that provide aspects of both street and off road tires that are intended for a mixture of both uses. These generally have a smooth center ridge with tread around the side. Although such tires are not as good for a certain specific use, they often provide a good compromise and are a good choice for the less serious rider and those wanting to save the costs and time have having to switch between multiple tires. Tubeless tires are also available for use in mountain bikes. These are more expensive and generally require special wheels but they offer some advantages over conventional tires. Tubeless tires can be run at lower tire pressures than conventional tires without getting pinch flats. Lower pressure makes for a smoother ride and offers better traction on rough terrain.

There are a variety of tires to choose from on a mountain bike. Knobby tires
(pictured on the left) provide for excellent off road traction while slicks (right)
provide a smooth ride with little rolling resistance. The tires pictured between
between the two extremes are of the hybrid variety.

Braking systems also vary from bike to bike. The cheaper discount store models tend to use cantilever style brakes which are not always the most effective. Entry level bike shop models tend to use linear pull v-type brakes. These tend to work very well for most riders. Those willing to upgrade and pay a couple hundred dollars more can opt for disc brakes. Disc brakes offer longer pad life, longer rim life, and greater stopping ability, especially in mud and water. These brakes somewhat resemble the disc brakes found on cars and motorcycles. Unlike traditional bike brakes, disc brakes do not rub against the rims to provide stopping power.

Rear disc brakes are shown here. Unlike traditional brakes, these
do not rub against the rims, offering longer rim life.

During rough use, parts can break, so be prepared while riding. The most common problem experienced during off road riding is a flat tire. Rocks, thorns, and glass can puncture through the tire to the inner tube and cause a flat. Flat tires can also be caused by low tire pressure. When hitting a bump with low tire pressure, the tire compresses against the rim, pinching the inner tube in between. These flats are called pinch flats or “snakebite” flats due to the appearance of four holes in the inner tube, resembling a snakebite. They are best prevented by keeping tire pressure at 55-65 psi. It is a good idea to either carry a patch kit and/or a spare inner tube along with a small hand pump while riding. When fixing a flat tire, be sure to check and see if the object that punctured the tire is still present and remove it if it isn't gone. Tire liners such as Mr. Tuffy can be inserted into the tire, adding a barrier against punctures. Although they add weight, they may be a good idea if riding on rocky terrain, areas with thorns, or where there is lots of broken glass. Self-sealing inner tubes, which are supposed to be self-repairing, are also sold. Other parts can also break or be rattled loose while riding so it is a good idea to carry a small set of tools. Bike stores will be glad to sell small bags, tools, tire pumps, and other accessories designed to be carried on a bike.

Another accessory needed for safety is a helmet. A properly fitted helmet is a necessity on rough and potentially dangerous rides. Since a helmet is essentially made of Styrofoam covered with hard plastic shell, they generally only withstand one crash. After any mishap, always inspect a helmet and replace if any damage is found.

In order to perform well and last, a mountain bike needs cleaning and maintenance. After each ride, the chain and other drive train components should be cleaned and lubed. Teflon and wax based dry lubes are more expensive but tend to attract less dirt, making care easier. They are well worth the extra cost. Motor oil, WD-40, etc. should not be used as it attracts dirt extremely well. Tune-ups should be performed as needed. Thorough cleanings and adjustments should be done at least once a year or more depending on use.

Before buying a mountain bike from a dealer, test ride all bikes being considered, even if by simply taking the bike around the block. Make sure that the seat and other parts are adjusted properly in order to give the bike a fair test. Check out warranty periods from both the dealer and the manufacturer. Look for at least a year warranty on all parts and a lifetime warranty on the frame. Insist upon getting at least one free tune-up since new bike components will always need adjustments after an initial break in period.

One important thing to note when purchasing a bike is durability. A more expensive bike doesn’t always mean the parts will be longest lasting. Some very expensive bikes use ultra light materials that tend to actually wear out faster than their cheaper alternatives. These are often best only for racing or other professional uses. Although theft is not a large concern at UMR, expensive bikes are recognizable to the trained eye and are more likely to be stolen. One might not want to buy the most expensive bike to simply ride around campus. For one thing, a person doesn’t need a titanium frame to just ride around town and others might not be so careful with your bike as they force their Huffy into slot next to your bike on the rack. It is definitely a good idea to consider the intended use of a mountain bike before buying a very expensive model. With consideration for the rider and the intended use, a mountain bike can be a very useful, enjoyable, and long-lasting purchase, without having an excessive cost.

Both mountain bikes and their riders should be able to withstand the rigors of
hard outdoor use. In this case, a creek is being crossed at a high rate of speed.

Thanks to Dan and Brian Fuhrmann of Route 66 Bicycles in downtown Rolla for some of the photographs and information presented in this article. Dan and Brian are two UMR Alumni who purchased the shop in October 2002. The two continue to promote cycling in the Rolla area and carry a wide variety of bikes both new and used. The shop is located at 805 N. Rolla St. and may be reached at 573-368-3001.