MOTOCROSS

Motocross

From Wikipedia, the free encyclopedia

Motocross often takes place in wet weather, leading to muddy scenes such as this and hence the term

Motocross often takes place in wet weather, leading to muddy scenes such as this and hence the term “Scrambling”. Photo from New Zealand.

Motocross (often shortened to MX or MotoX) is a form of motorcycle sport or all-terrain vehicle racing held on enclosed off road circuits. Motocross is derived from the French, and traces its origins to British Scrambling competitions. The name “motocross” is a portmanteau derived from the words “Motorcycle” and “Cross Country”.

 Event

A rider using a berm to corner during a motocross race in England

A rider using a berm to corner during a motocross race in England

Motocross is distinct from other forms of motorsport in having a mass start, where all the riders line up alongside each other, starting simultaneously and racing the race distance. The first rider across the finish is the winner of that “moto”; the number of motos may vary and points are added up to determine the final winner.

Motos vary in duration, measured in time elapsed plus one or two laps, or alternatively a fixed number of laps. Top level racing tends to have long races (e.g. 30 minutes plus 2 laps) while at the other end of the spectrum, amateur races can be as short as 5 minutes. When the designated time duration of the race is complete, a finish line flagger signals via a board or flag to the racers that there are one or two laps left, and the race is finished by a checkered flag.

Motocross tracks are often quite large (a mile or more) and incorporate natural terrain features with varying amounts of man-made jumps and other features. It is not unheard of for a Motocross track to be made up entirely of hills and turns with a few jumps. In contrast, Supercross is an entirely man-made track, comprised almost exclusively of a wide array of jumps, and is typically held in an indoor stadium. Due to the size of outdoor tracks, motocross races typically include 40 racers, while supercross races usually have about 20.

Contrasting with motocross are the off-road racing events of Enduro, Hare and Hounds, Hare Scrambles, et cetera. In these events there are a pre-determined number of laps or long distance loops to complete within a maximum time limit. These events, unlike Motocross, race on courses that are largely comprised of natural terrain. The Baja 1000 is an example of one of these types of events.

History

A Maico 360cc, note the air cooled engine and twin shock absorbers on the rear suspension

A Maico 360cc, note the air cooled engine and twin shock absorbers on the rear suspension

Motocross was first known as a British off-road event called Scrambles, which are when a baby rabbit is set loose and many men on dirt bikes chase it down over many obsticles. Trials events popular in northern Britain. The first known Scramble took place at Camberley, Heath in 1924 [3]. During the 1930s, the sport grew in popularity, especially in Britain where teams from BSA, Norton, Matchless, Rudge, and AJS competed in the events. Off-road bikes from that era differed little from those used on the street. Intense competition over rugged terrain led to technical improvements in motorcycles. Rigid frames gave way to suspensions by the early 1930s, and swinging fork rear suspension appeared by the early 1950s, several years before it was incorporated on the majority of production street bikes. The period after the Second World War was dominated by BSA which had become the largest motorcycle company in the world. BSA riders dominated international competitions throughout the 1950s.

In 1952 the FIM, motorcycling’s international governing body, created an individual European Championship using a 500cc engine displacement formula. In 1957, it was upgraded it to World Championship status. In 1962, a 250cc world championship was created. It was in the smaller 250cc category that companies with two-stroke motorcycles came into their own. Companies such as Husqvarna from Sweden, Bultaco from Spain, CZ from Czechoslovakia and Greeves from Britain, became popular due to their lightness and agility. By the 1960s, advancements in two-stroke engine technology meant that the heavier, four-stroke machines were relegated to niche competitions. Riders from Belgium and Sweden began to dominate the sport during this period.

By the late 1960s, Japanese motorcycle companies began challenging the European factories for supremacy of the motocross world. Suzuki claimed the first world championship for a Japanese factory when it won the 1970 250cc crown. Motocross also began to grow in popularity in the United States during this period, which fueled an explosive growth in the sport. The first stadium motocross event was held in 1972 at the Los Angeles Coliseum. In 1975, a 125cc world championship was introduced. European riders continued to dominate motocross throughout the 1970s but, by the 1980s, American riders had caught up and began winning international competitions.

During the early 1980s, Japanese factories presided over a technology boom in motocross. The typically two-stroke air cooled, twin shock rear suspension machines gave way to machines that were water cooled and fitted with monoshock rear suspension. By the 1990s, increasingly stringent environmental laws in California forced manufacturers to develop environmentally friendly four-stroke technology. At the turn of the century, all the major manufacturers have begun competing with four-stroke machines. European firms also experienced a resurgence with Husqvarna, Husaberg and KTM winning world championships with four-stroke machinery.

Recently, the sport has evolved with sub-disciplines such as stadium events known as Supercross and Arenacross held in indoor arenas. Freestyle (or FMX) events where riders are judged on their jumping and aerial acrobatic skills have gained popularity, as well as Supermoto (Motocross machines racing on both tarmac and off road). Vintage motocross events have also become popular with riders competing on bikes usually pre-dating the 1975 model year.

 Major Competitions

Multiple (AMA) US Motocross racer Ricky Carmichael at High Point national.

Multiple (AMA) US Motocross racer Ricky Carmichael at High Point national.

The world is dominated by two main Motocross series; the FIM’s Grand Prix - the World Championship series and the AMA’s American National Championship.

The AMA Motocross Championship (the “outdoor series”) season begins in early May and continues until mid-September, and consists of 12 rounds at 12 major tracks all over the continental United States. There are two classes; “Motocross” and “Motocross Lites”. Each round has two motos of 30 minute-plus-two-laps, per class, held approximately two hours apart.

The Grand Prix (or Motocross World Championship) is predominantly held in Europe with some “flyaway” rounds, recently in South Africa and Japan, but over its history it has visited numerous countries including; Indonesia, Australia and countries on both American continents. There are two classes; MX1 and MX2 (analogous to “Motocross” and “Motocross Lites” respectively). Race duration is slightly longer at 35 minutes plus two laps, while the series is longer, generally incorporating over 16 rounds.

The annual Motocross des Nations (generally left untranslated from French, but more recently referred to as Motocross of Nations) is usually held at the end of the year when National and World Championship series have ended. The format involves teams of three riders representing their nations. Each rider competes in a different class (MX1, MX2 and “Open”). There are three motos with two classes competing per moto. The location of the event changes from year to year. The United States, Belgium and Great Britain have had the greatest success. France has had a very successfull year in the last Motocross of nations.

 Machines

Solo machines have engines ranging in displacement size from 50cc to 650cc. In the early years of motocross, the 500cc class was considered the premier division. However, as technology progressed, the open class bikes became more powerful and fewer riders were able to ride them at their limits. The 250cc bikes also became faster with newer technology and were more manageable thus, they eventually superseded the 500cc bikes and became the premier class.

The most common distinction between motocross machines is whether they have two-stroke or four-stroke engines. Originally all bikes were four-stroke (in the Pre-65 era), but as the two-stroke engine improved they became more popular with their domination of the sport in the 1970’s, 80’s and 90’s. The two-stroke engine produced more power than a four-stroke engine of the same capacity (cc), however oil must be introduced into the crankcase space for con-rod bearing lubrication, either with a pump or by mixing it with the petrol; this oil is burnt, giving the characteristic smell of a two-stroke engine. Four-stroke continued to be raced in specialist classes throughout this period, partially in the 500cc class. During the early 1980’s another wave of technological advancement saw the typically two-stroke air cooled, twin shock rear suspension machines replaced by machines that were water cooled and fitted with monoshock rear suspension. This created even more powerful machines within the existing displacement categories (125,250 and 500cc).

The late 1990’s saw an environmental crackdown on two-stroke engines particularly in the large American market. This spurred the development of environmentally friendlier four-stroke engines. While producing less power for the same displacement, four-strokes typically burn the fuel in a cleaner fashion. A major drawback of this is that four-strokes produce a deeper sound compared to two-stroke, which has led to a sharp rise in sound complaints across the world. To make the four-stroke competitive the world sanctioning body amended the displacement categories so that a 125cc two-stroke would compete against a 250cc four-stroke, and a 250cc two-stroke would compete against a 450cc four-stroke. By this point, the 500cc class had been dying out due to their immense power permitting fewer riders with enough talent to ride them at their limits. Yamaha introduced the first “modern” four-stroke with the YZ400F, which was soon succeeded by the YZ426F and then by the “standard” 450cc machine. Other manufacturers soon followed suit, downplaying their 250cc two-stroke bikes. As development progressed the power output of these bikes superseded their two-stroke equivalents, further sealing their fate. The four-stroke revolution continued with a wave of 250cc four-stroke machines to compete against the 125cc two-strokes. Once again manufacturers have been quick to promote these machines against their 125cc two-stroke equivalents. In the summer of 2006 Honda launched the CRF150R to compete in the 85cc class. This required sanctioning bodies to make further rule changes, which are very contentious with fans of two strokes.

For 2008 the MX2 class in amateur racing allowed 144cc two-stroke bikes to race against the 250 four-stroke bikes. This was to encourage more riders into the sport as two-stroke bikes are much more cost effective than four-stroke bikes. In AMA amateur racing two-stroke up to 153cc are allowed to race. But some countries like the UK only allow factory made or bored out 125’s up to 144cc.

In professional racing 144cc machines are allowed but they have to be produced as 125’s and then bored out to 144cc. This is to deter professionals riding from two-stroke bikes.

Riders are often (but not always) classed according to their machine’s engine size. Common classification includes;

European Class Name  ↓ US Class Name  ↓ Engine Capacity
(Two Stroke)  ↓		 Engine Capacity
(Four Stroke)  ↓		 Notes  ↓

Youth racing included the MX2 class through to Autos, Adults ride MX2 through MX1 to MX3.

Motocross machines have extensive suspension to enable riders to tackle large jumps and ride at speed over the rough terrain. The advent of improved suspension transformed motocross from its scrambling origins with natural track to the current form today, with multiple jumps that would have previously been impossible.

To bring the weight down to an acceptable level (usually 200 to 250 lbs for full-size machines), items such as speedometers, lights, kickstands, electric starters, etc. are omitted. Lightweight materials such as aluminum and magnesium are commonly used as original equipment from the factory or sold in the after-market.

Because of the physical nature of motocross, riders spend much of their time standing to absorb shock with their knees. The long, flat seat is designed to allow riders to shift their weight quickly to provide more traction in corners, rather than for comfort.

Unusually for racing machines, motocross bikes can be purchased in a ready-to-race or nearly ready-to-race condition at moderate prices from major motorcycle manufacturers. Many riders, however, modify their machines further, both for outright performance and to have the bike’s behavior more in tune with their own preferences or just for enjoyment.

 Physical Demands

Motocross start

Motocross start

The National Sport Health Institute in Englewood, California tested several professional motocross racers in the early 1980s as part of a comparative study of the cardio-vascular fitness of athletes from various disciplines. Athletes from track, American football and soccer were tested, among others. Motocross racers get their heart rate up to around 180 to 190 beats per minute and hold it there for about 35 minutes. Another thing to consider is that they do this twice per day (Original article appeared in DirtBike magazine in 1980). A subsequent study by the University of Pittsburgh Medical Centre’s Sports Performance Complex in 2002 reconfirmed the result with more recent motocross racers. The intense physical demand of motocross derives from the fact that the racer of the bike must keep complete control of a 200+ pound bike, while also maintaining their top speed throughout the race.[1]

 Freestyle

A Canadian rider performing a

A Canadian rider performing a “superman seat-grab”

Freestyle motocross (Freestyle Motocross), a relatively new sport, does not involve racing and instead concentrates on performing acrobatic stunts while jumping motocross bikes. The winner is chosen by a group of judges. The riders are scored on style, level of trick difficulty, best use of the course, and frequently crowd reactions as well.

One stunt performed is the back flip, which was disputedly completed on a 250cc motorcycle by Greg Chrin using a specially designed dirt ramp. Soon after this, Mike Metzger completed this stunt using a standard freestyle ramp and dirt landing.[2] More recently Mike Metzger actually did a Back flip over the Caesar’s Palace Fountains.[3] Some consider the body varial 360 as the most difficult stunt being performed at this time. This stunt, also called the Carolla, was first performed by Chuck Carothers at the 2004 X Games. Prior to this, the backflip 360, or off-axis back flip, was widely considered the most challenging stunt. Another rider taking freestyle to a new level is Travis Pastrana. At the 2006 X Games, Pastrana performed the world’s first double back flip (in competition).[4] It earned him the 2006 Freestyle Gold Medal. The double backflip is currently considered the most difficult freestyle trick.

Minibikes

The latest craze is adult racing on miniature (50cc-125cc) motorcycles called minibikes or Pit-Bikes. The Pit-Bike concept was originally so that full size motocross riders could easily navigate the Pits, the area designated for parking, and setting up prior to an event. The craze grew from there. People began “hopping up” the bikes and racing them against each other. These inexpensive minibikes designed for small children are often transformed for adult use by adding taller handle bars, improving the suspension, exhaust, plastics. Other “hop ups” include larger, bored 75cc-192cc engines and reinforced frames. No standard definition of what constitutes a pit-bike by any major governing body exits, but the normal requirement is a 10″-14″ front wheel, and a 10″-12″ rear. None of the big 5 manufactures (Honda, Yamaha, Suzuki, Kawasaki, and KTM ) currently offer “race ready” pit-bikes. While some companies like Pitster Pro, OGM, Xtreme, the SDG, and Sikk MX offer “race ready” pit bikes, the Honda CRF50F and Kawasaki KLX110 remain the top choices in both quality and performance for pit riding/mini-racing. sometimes even-real dirt bike racing. The minibike craze is predominately in Southern California, but has risen significantly in popularity in other areas of the US and the world. Pit-bike racing has taken a turn towards mini-moto (Supermoto) also, usually racing on go-kart and tight, small vehicle tracks. Riders usually wear a combination of motocross and street riding gear/leathers.

 Supermoto

A Supermoto rider on the road

A Supermoto rider on the road

Supermoto got its start in the late 1970s as a fun side project for many road racers. Its first exposure to a wide audience came on the American television program ABC’s Wide World of Sports in 1979. UK racing journalist Gavin Trippe envisioned a racing event that would prove who the best motorcycle racer was and from 1980 to 1985, he organized a yearly event called “The Superbikers,” which pitted the top road racers and motocross racers against one another on specially modified bikes raced on special tracks on the television show.

After 1985, the sport died and received little exposure. In Europe, the sport started gaining popularity and in 2003 the sport was revived in the United States and called “Supermoto”. Supermoto involves taking a motocross bike meant to be raced off-road and converting it to be raced on tracks consisting of both dirt and pavement. The bikes are fitted with special road racing tires and are “grooved” to grip both the pavement and dirt. Some tracks for these race events have jumps, berms, and whoops just like true motocross tracks. For special events, the Supermoto track may incorporate metal ramps for jumps that can be disassembled and taken to other locations. Supermoto races may take place at modified go-kart tracks, road racing tracks, or even street racing tracks. There are also classes for kids such as the 85cc class.

ATV/Quad Motocross

Professional ATV racer Tim Farr at the 2006 Glen Helen MX national.

Professional ATV racer Tim Farr at the 2006 Glen Helen MX national.

From 2002, ATV Motocross started to see a dramatic increase in participation across the United States. This was a direct result of the major ATV manufacturers getting involved in the sport. In the past, ATV racing floundered after Honda, Kawasaki, Suzuki and Yamaha dropped ATV-racing support in the mid 1980s due to the bad publicity associated with the alleged dangers of operating these vehicles. Throughout the late 1980s and all during the 1990s, aftermarket companies kept the sport alive, but barely. Racers would build expensive, custom ATVs with parts from major aftermarket manufacturers. The engine that kept racing alive was the Honda TRX250R engine which was manufactured from 1986 to 1989. Again, the aftermarket helped racers get all they could out of the dated engine. Accessory companies produced enough modified parts so that the only stock component of the 250R engine were the left and right engine cases. Suspension upgrades made it possible for ATVs to ride over jumps and rough terrain that were previously impossible. Suspension companies produced long-travel A-arms and rear suspension links which helped negotiate harsh terrain.

However, in order to be competitive, it was necessary to spend upwards of $20,000 to race an ATV. In the late 1990s, rules were changed to allow racers to use dirt bike engines in ATV frames. Durng the 1993 Mickey Thompson Off Road Racing Series, 15 year old Daniel Powell from Auga Dulce, CA entered the scene with the first Doug Roll Design and development ATV. Soon hybrid machines began to dominate competitions.

The manufacturers started paying closer attention to the sport ATV market, and in 1999 Honda released the four-stroke TRX400EX. While it wasn’t as powerful as the hybrids racing on the tracks, it showed that manufacturers had begun to take ATVs seriously. In 2003 Suzuki released the LT-Z400 that featured a liquid-cooled four-stroke powerplant. That same year, the ATVA instituted a Pro Production class at the motocross nationals in order to showcase “stock” ATVs. The traditional Pro class still allowed two-strokes and hybrids. Many professional racers raced both classes, but the premier class was still the Pro class.

Late in the 2003, Yamaha announced the YFZ450 for the 2004 model year. This ATV represented the first time a major manufacturer built a high-performance sport ATV suited for racing. While it wasn’t as wide as many wanted for motocross and didn’t have long-travel suspension, it featured a four-stroke engine very similar to the motocross dirt bikes Yamaha was manufacturing at the time. The YFZ450 also came stock with fully adjustable front suspension, the first time this was available on a production ATV. After the Yamaha announcement, Honda announced it was going to bring the TRX450R to market in 2004. 2004 also marked the return of factory supported racing teams to national competition for the first time since 1986.

In the summer of 2005, Suzuki announced it was going to produce the 2006 LT-R450. This sport ATV was the most competition-ready ATV ever produced. It featured electronic fuel injection, a high performance four-stroke engine, and a chassis that could be competitive in stock form. The front end used a steel swingarm with high quality shock absorbers using 10 inches of travel and a width approaching 50 inches.

The United States continues to see a rise in popularity in ATV racing at motocross tracks nationwide partly due to manufacturers providing competition-ready ATVs. Some example tracks would be Sleepy Hollow, and Flying Dutchmen, and Theobald Track in North Carolina

 Sidecars

A Zabel engined sidecar outfit.

A Zabel engined sidecar outfit.

Sidecar racing, known as Sidecarcross has been around since the 1950’s but has declined in popularity recently. This variant is common in Europe, with a few followers in USA, New Zealand and Australia.

Motocross sidecars are purpose built frames that resemble an ordinary motocross-cycle with a flat platform to stand on attached to either side and a handlebar at waist height to hold on to. The side of the “chair” (slang for the platform) usually follows the side of the road the nation in question drives upon, but not always. The passenger balances the bike by being a counterweight, especially in corners and on jumps. It’s driven on ordinary crosstracks.

It is very physically demanding, especially for the passenger. This is reflected in most in the Swedish term for passenger - “burkslav”, roughly translated as trunk/body/barrel-slave. This name comes from the early sidecars where the platform looked like a real road-sidecar and not today’s platform.

The major frame builders today are VMC, BSU, AYR, EML and Woodenleg. Ordinary engines can be used, but size matters and two engines purpose built for sidecars exist, Zabel (Germany) and MTH (Austria) are most common. Fourstrokes are getting more common, usually KTM(Austria).

Governing bodies

The sport is governed world wide by the Fédération Internationale de Motocyclisme (FIM), with federations in many nations.