Mini rider parents may find it difficult in deciding between the 150cc vs. 85cc. Clearly, the 150cc engine is bigger, is a 4-stroke compared to the 2-stroke of the 85, and thus offers more power. But a true rider knows bigger is not always better. The best dirt bike is what suits your riding style, experience, where you ride and of course your comfort level.
The 85cc engine may lack the size of the 150cc but fear not, the 85 is not for beginners, has plenty of power and it's 2-stroke engine is already a plus amongst the 2-stroke community. An 85cc dirt bike engine packs enough wallop to easily get you over a triple and the cost is nowhere near a 150cc dirt bike.
The following is what you should investigate before deciding between an 85cc dirt bike or a 150cc dirt bike:
Budget
The 85cc bike is considerably less expensive than a 150cc bike. In fact the difference between two of the more popular selections - the Honda CRF150 vs. the Suzuki RM85 - is about $1,000. The 85 is not only cheaper off the showroom, but it's also easier and cheaper to maintain. The RM85 is a proven dirt bike, is well-built and can handle just about anything you ride it on...or in to.
The 85cc and 150cc bikes are not for beginners but are a stepping stone to bigger and better. Once skills get established, many riders still opt for the 85cc machines for racing. While the 150cc does have more horsepower, the power delivery is better suited towards newer riders and offroad riding. It provides a much smoother powerband and is more forgiving in these conditions.
If you're on a budget - get the 85cc dirt bike.
Where You Ride
If you enjoy riding on the weekends and dirt biking is more of a hobby to be enjoyed on trails with friends then the 150cc bike is a good choice. It provides great power, is versatile and sturdy to rough moderate terrain and whatever obstacles you'll ride over or through.
The 150cc bike is powerful enough to try your hand at motocross but don't expect a Top 5 finish, much less a top 10 finish. While the rider really makes the difference, the 85 is the choice for competitive racers. The serious racer who competes, rides hard and enjoys the launch from a triple needs a more powerful bike. Not to mention, in AMA competition the 150cc 4 stroke is not allowed in the 85cc class and can only be ridden in the Supermini classes. If you spend time and money on racing and enjoy the competitive nature that motocross offers - stick with the 85cc.
Photo: Honda Powersports
The 150cc bike is certainly no slouch but is really best for trails, open fields and the occasional track session. To really compete and push yourself to the limits of racing grab the 85cc and once you've mastered it, the 125's and 250f's won't be too far around the corner.
How You Ride
How you ride gels with where you ride. The 150cc engine is hard to beat for an afternoon with your buddies trail riding. It is great for the new rider just learning and will help ease some of the frustration with learning as the bike is much easier to ride. You won't be fouling spark plugs all day and the power band is much more mellow compared to the 85cc models.
However, as your skills on the bike crescendo the urge to dig in a bit is natural and you'll find the 150 does have power limits. Once you're comfortable on the 150 there's little more you can do to further increase your dexterity and proficiency on the bike - the 150 only pushes so hard. Therefore, the aggressive rider, and anyone wishing to test their competitive nature and improve their riding skills should ride the 85cc. The aftermarket following for performance parts on the 85cc machines is incredibly large. You can find a plethora of aftermarket parts and services including engine building and big bore kits to really make the 85s scream.
Comfort Level
Dirt bike riding is not for everyone. It's exhilaratingly fun but also dangerous. The 150cc bike offers much more than a beginner's 100cc or 125cc 4 stroke bike but is not overly powerful to scare someone away from the sport for good. A 150cc bike provides hours of fun for the weekend rider looking to whisk their way through the woods, mountains or any dirt bike ready trail.
Max Miller Riding an 85
The 85cc bike is truly on the cusp of professional riding. This is the bike for anyone who gears up every weekend, races competitively and is interested only in outright performance. On the motocross track, if the 150 gives you a taste of how awesome our sport is, the 85 is the full course meal. If you're comfortable throwing whips, pounding the whoops and dragging bars in the corners - get an 85cc.
Power
In terms of power, there is really no comparing the 2-stroke 85cc and 4-stroke 150cc engine. The 150cc engine is a fantastic ride that accomplishes what the average, weekend rider needs. The bottom line between the 85cc and the 150cc, therefore, come down to power. The 85cc, like any 2-stroke, gives that screaming top end power perfect for racing, but for more bottom-end power you'll want the 4-stroke in the 150.
If you have no plans to race and enjoy a day on the trail then get the 150cc bike not only because of the ease of use - but the cost difference allows you to focus some of your efforts on protective riding gear which you'll need regardless of the size of your dirt bike.
Photo: Honda Powersports
Conclusion
As with all purchases the choice is up to you. Cost is a primary motivator for most riders and if all you really want to do is get out and ride, the 150cc bike is an optimum choice. The 150 does have an initially higher cost but is more forgiving and does not have the nearly as big of a following for racing. The 85 while initially cheaper, is the bike for the racers and has a much larger aftermarket following and can be modified to outrun a 150 easily under race conditions.
Here's the bottom line: The 150s are a great bike and do have more power stock. They can compete but as you'll see don't have a huge following except at the local level because 150s are allowed in the 85 class locally, but are not allowed to compete in the 85 class on the national level (AMA and NMA sanctions) and are relegated to the Supermini classes which can be up to 115cc 2-strokes.
Additionally, the 150s can compete in this class power-wise with the bored and stroked 85s (the supermini class was always 85s modified to 105cc to 115cc before the 150 4-strokes came along) and therefore are not overly popular at the moto track. They are great learner bikes compared to 85s and are popular with female riders.
However, if you strive to ride faster and harder and/or want to try your skills against other accomplished riders, then the 85cc bike offers all the tools to help you become a Mini National Champion.