motocross – AdventureBikeTroop

One of the most important factors to consider when choosing a dirt bike is the seat height. Dirt bikes tend to have much taller seats than any other motorcycle which can be intimidating for beginner riders. The average dirt bike has a seat height is 34 inches (863 mm). With a seat height of 38.6 inches (980 mm), the Yamaha YZ125 is the tallest dirt bike, while the Yamaha PW50 kiddies bike has the shortest seat height of 18.7 inches (475 mm). Dirt bikes are tall due to long travel suspension, big wheels for off road riding, and a neutral seating position. Before we look at how to choose the correct size dirt bike for you and the reasons why dirt bikes are so tall, let's have a look at the seat heights of all the major manufacturers of dirt bikes. List of Dirt Bike Seat Heights Dirt bikes can be classified into three main categories: competition, recreational, and kiddies bikes. Competition dirt bikes are very tall due to their long travel suspension that is necessary to soak up big jumps on motocross tracks. These bikes include 125 cc and 250 cc two-stroke motorcycles, and 250 cc, 350 cc, and 450 cc four-stroke dirt bikes. The average competition dirt bike has a seat height of 37.6 inches (955 mm) which is too tall for most riders to put both feet flat on the ground. The Yamaha YZ 125 and YZ250 are the tallest dirt bikes, while Husqvarna's competition dirt bikes are the lowest at 37 inches. The Yamaha YZ125 is the tallest dirt bike with a seat height of 38.6 inches (980 mm) (Source: Yamaha USA) Recreational dirt bikes and kids bikes (except the very small 50's) have similar seat heights. Recreational dirt bikes generally have engine sizes between 100 cc and 300 cc (mostly four-stroke), while kiddies bikes have either 50 cc, 65 cc or 85 cc, two-stroke engines. The average non-competition dirt bike has a seat height ranging from the Yamaha PW 50 kiddies bike at 18.7 inches (475 mm) to the Kawasaki KLX 300 R at 36.4 inches (925 mm). The tallest kiddies bike is the KTM 85 SX or Gas Gas MC 85 at 35 inches (890 mm). The table below contains all the seat heights and engine sizes (in cc) of all the dirt bikes currently (2021/22) available from the major motorcycle manufacturers’ websites. For seat heights on other types of bikes, check out this comprehensive post. Bike ModelSeat Height(Inches)Seat Height(mm)Engine size(cc)Yamaha YZ12538.6980125Yamaha YZ250F38.2970250Yamaha YZ25038.2970250Yamaha YZ250X38.2970250Honda CRF450RWE38965450Honda CRF450R38965450Honda CRF450RX38965450Honda CRF250RX38965250Yamaha YZ450F38965450Honda CRF450X37.9963450Honda CRF450-S37.8960450Honda CRF250R37.8960250Suzuki RM-Z45037.8960450Yamaha YZ450FX37.6955450Yamaha YZ250FX37.6955250Yamaha YZ125X37.6955125Yamaha WR450F37.6955450Yamaha WR250F37.6955250Kawasaki KX45037.6955450Kawasaki KX450 SR37.6955450Suzuki RM-Z25037.5953250Kawasaki KX25037.4950250Kawasaki KX450 X37.4950450Suzuki RMX450Z37.4950450Gas Gas MC12537.4950125Gas Gas MC25037.4950250Gas Gas MC250F37.4950250Gas Gas MC350F37.4950350Gas Gas MC450F37.4950450KTM 450 SX-F37.4950450KTM 350 SX-F37.4950350KTM 250 SX-F37.4950250KTM 250 SX-F Troy Lee Designs37.4950250KTM 250 SX37.4950250KTM 150 SX37.4950150KTM 125 SX37.4950150Kawasaki KX250 X37.2945250Husqvarna TC25037940250Husqvarna FC25037940250Husqvarna FC35037940350Husqvarna FC45037940450Kawasaki KLX300R36.4925300Kawasaki KLX230R36.2919230Kawasaki KLX230R S35.4899230Gas Gas MC85 19/163589085KTM 85 SX 19/163589085Honda CRF250F34.8884250Yamaha YZ85LW34.888485Husqvarna TC85 (19/16)34.487585Yamaha TT-R23034.3871230Kawasaki KX10034.3871100Kawasaki KX11234.3871112Gas Gas MC85 17/1434.186585KTM 85 SX 17/1434.186585Kawasaki KLX140R F33.9861140Suzuki RM8533.585185Suzuki RM8533.585185Yamaha YZ8533.184185Honda CRF150R32.8833150Kawasaki KX8532.783185Suzuki DR-Z125L32813125Yamaha TT-R125LE31.7805125Kawasaki KLX140R L31.5800140Honda CRF125F BIG WHEEL30.9785125Kawasaki KLX140R30.7780140Kawasaki KX6529.975965Yamaha YZ6529.775465Husqvarna TC6529.575065Gas Gas MC6529.575065KTM 65 SX29.575065Honda CRF125F29.1739125Kawasaki KLX110R L28.7729110Kawasaki KLX110R26.8681110Yamaha TT-R110E26.4671110Husqvarna TC5026.266550Gas Gas MC5026.266550KTM 50 SX26.266550Honda CRF110F25.9658110Suzuki DR-Z502255950KTM 50 SX Mini2255850Yamaha TT-R50E21.955650Honda CRF50F21.654950Yamaha PW5018.747550Dirt bike seat heights comparison table (Source: Manufacturers’ websites) I have not distinguished between two-stroke or four-stroke dirt bikes since there is no difference in the seat height between similar capacity bikes of these two engine types. Why are Dirt Bikes so Tall? Dirt bikes are used to race (or at least ride fast) over technical terrain. In professional competitions, dirt bikes often jump high through the air and need to be able to soak up the landing without falling apart. In hard enduro, dirt bikes need to clear obstacles and absorb rocky terrain without rattling to pieces. The terrain that dirt bikes have to face requires the machine to have specific attributes that all contribute to a tall seat height. Long suspension travel Dirt bikes have long-travel suspension in the front and rear in order to soak up irregularities on gravel and dirt roads as well as motocross tracks. Dirt bikes are often used to ride over rocky terrain, where suspension travel is important to keep traction. In motocross competitions, dirt bikes have to jump very high through the air and be able to soak up the weight of the bike and the rider when it lands again, without bottoming out. The long suspension travel found on dirt bikes are the main reason for the tall seat height. Dirt bikes need long-travel suspension to soak up uneven terrain and massive jumps (Source: Yamaha USA) Neutral seating position Dirt bike riders need to sit comfortably in a neutral body position so that they can balance the bike over slow obstacles, or move around when cornering fast. This upright seating position, with the rider's feet under his or her body with a 90 degree bend in the knees, means that the foot pegs cannot be too close to the seat, like on a street bike. Dirt bike riders often stand while riding over uneven terrain or jumping through the air. This is to prevent getting bucked off the seat, but also to assist with shock absorption by bending the knees. A tall seat that is far enough from the foot pegs assists the rider to transition quickly between the seated and standing position. High ground clearance The foot pegs also cannot be too low to the ground to lower the seat height because then the bottom of the bike's frame would hit rocks and other obstacles in the road. In order to clear rough terrain, dirt bikes need a high ground clearance. This is achieved by the long travel suspension, tall seat height, and big wheels. Big wheels Big wheels roll over obstacles (instead of crashing into them) much easier than small wheels. Most dirt bikes have a large 21 inch front wheel and a slightly smaller 18 inch rear wheel. These sizes have a large enough circumference to roll over most irregularities on gravel roads and to even clear logs as high as the radius of the front wheel with ease. Kiddies dirt bikes have smaller wheels to lower the seat height, while dirt bikes for older youths have different wheel size options, for instance the KTM 85 SX come with either 19/16 inch wheels (front and rear respectively) or 17/14 inch wheels for shorter riders. How to Choose the Right Size Dirt Bike There are many different factors to consider when choosing a dirt bike, including engine capacity, power output, 2-stroke vs 4-stroke, seat height and weight. Since this post focuses on seat height, we'll look at the dimensions of the bike only. If you want a more detailed post that takes all the variables into consideration, check out this post. There is a dirt bike that's the right size for you, no matter how short you are (Source: Yamaha USA) The only way to know for sure whether you will be comfortable on a dirt bike is to take it for a test ride. This is not always possible, especially a brand new bike. The second-best alternative is to at least sit on the bike to get a feel for the weight distribution and your ability to keep it upright. It helps to be able to touch the ground comfortably with both feet at the same time. Fit-toeing is fine. If you are still doing some online research before narrowing down a short-list of dirt bikes to go test, you may want to measure your inseam. This is the distance between the ground and your crotch (with your feet flat on the ground). You can compare this measurement with the table of seat heights presented earlier in this post. Be mindful of the fact that the shape of the bike's seat will also affect your ability to touch the ground comfortably. A wider seat will make it more difficult, while a narrow seat (like those found on most dirt bikes) will make it easier to reach the ground. Take note: Although it does inspire confidence, especially in beginner riders, you don't have to be able to flatfoot it on either side. In fact, most professional riders cannot put both feet flat on the ground on their competition machines with very tall seat heights. Dirt bikes are generally very light and therefore easier to keep upright when standing still on your tip-toes. While riding, the seat height is totally irrelevant anyways. It is only when coming to a stop, or putting your feet down on uneven terrain when a tall bike can be intimidating for a beginner rider. As you gain experience, you will learn to control the bike while stationary. Conclusion Buying a new (or second-hand) bike is a special experience but for many, it is an expensive one. It is therefore important to make the right choice. You need to balance room for growth with immediate comfort and confidence. Many new riders believe they need to buy the biggest, fastest bike they can afford so that they can 'grow into it' as they improve their skills. I know, I've done the same. But believe me when I say, it is more fun riding fast on a slow bike, than riding slow on a fast bike. And you will learn much faster and become a better rider if you are not intimidated by your machine. You can always upgrade later. Enjoy the ride!