Two stroke vs Four stroke

Comparison between a four stroke 250 and a 2 stroke 250

Ever since four stroke dirt bikes have become competitive with the two strokes people have been arguing which one is faster and just all around better so lets compare them.

what is the horsepower difference?
The first difference between the Yamaha four stroke dirt bike and the two stroke is that the 4 stroke 250 produces 8500 rpm and 36 horsepower. The 2 stroke 250 makes about 46 horsepower at 11,300rpms. That’s a 10 horsepower advantage.
The difference between the KTM 250sx two stroke produces around 49.77 horsepower.

The KTM 250 four strokes make about 35.5 horsepower. So the 2 stroke has 13.22 more horsepower.
So no matter what brand of bike you get the 2 stroke is going to have more horsepower.

Horsepower doesn't matter if you don't have good torque so the torque comparison is:
The KTM 250 four stroke has 19.42 foot pounds of torque at 8600 rpm. While that is good torque the KTM 250 two strokes crushes it with 31.93 foot pounds of torque at 8000 rpm.

The KTM two strokes has way more than the four stroke. But its not the only brand were the 2 stroke has more horsepower the Yamaha 2 stroke has 30.6 foot pounds of torque. The YZ 250 four strokes has about 20.1 foot pounds of torque.

Is there a price difference?
Both the Yamaha 2 stroke and four stroke have the same retail of $7150
The 2012 KTM 250 two stroke is $800 cheaper than the 2012 KTM 250 four stroke. It retails for around $6899 (MSRP). The 2012 KTM 250 four stroke’s price is $7699

The author of dirt bike magazine said "Privateers could compete at a higher level for a lower cost. Even at the National level, engine mods on a two-stroke top out at around $1000—you can't buy the top-end parts for a four-stroke for that amount. "
Conclusion
My conclusion based on my research is that the 2 stroke is a faster bike. It is also cheaper bike. So why would you choose something that is more expensive and slower?

 Motocross action magazine said  "Without pulling any punches, every MXA tester thought that the 250SX two-stroke was a better race bike—lighter, faster, cheaper, better handling and easier to maintain. "

The whip

The most prestigious trick in racing is the whip. I'm going to tell you the way I do the whip and hopefully it will help you.
Picture of Justin Barcia whipping available at http://www.motorcycle-usa.com/PhotoGallerys/Justin-Barcia-unadilla.jpg

When going up the jump your body should be slightly forward on the bike. Being forward on the bike helps in bringing the back of the bike up and around. When approaching the jump let off on the gas. And begin to preload the suspension.


Next, start angling your bike towards the left side of the lip. If you are going to do a right turn your bike is already leaning towards your right foot. When you are at the base of the lip, you’ll want to twist the throttle throttle quick and then let go. This will give you more pop off the lip instead of powering through the lip like you think you would need to do. It is also important to let off the throttle right before the lip and preload the suspension to give you more lift.

Just after you leave the lip of the jump your head and shoulders will choose where your bike is going to go. As with any trick your body and bike will follow where your head and shoulders are aimed.

You should already be starting to look at your landing. There is no throttling here at all.
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Your bike should start to lay over easy now. You should not have to muscle a whip. It is more of a flow kind of thing rather than a muscle thing. Only your hands should be controlling the whip; it should flow the whole way through. Holding onto the bike with your right foot will help ensure you don’t lose the bike. Still, there is no throttle in this section of the jump.

Now you should be focused on your landing. Right when you get ready to land the whip, give it gas which will help straighten the bike up

The Holeshot

The holeshot refers to the first person to the first corner in racing. The holeshot is the key to the race. If you are last to the first corner, but you’re the best rider you still might loose. So you want to be the first person to the first corner. So im going to tell you the way I do it so maby it will help you inprove your starts.

The importance of a good start is accurately addressed by Gary Simics:

There are two races in motocross ; one is from the starting gate to the first corner. The other one is from the first corner to the checkered flag. When you do well in the first one the second one is normally a lot easier

First I choose a good gate to start at. I like to be in the middle or the left side. That puts you closer to the first corner because most of the first corners are right turns, because it allows you to keep you right foot on the back break.

Second I pack down the dirt were im starting to help me get more tracktion. When it’s a concrete start I sweep my gate and make sure there isnt any dirt on it because it will make you spin.

Then I slide up so that im sitting on the gas tank so that the bike want flip. By the time you do all this they should have the 30 second card up. When it goes sideways it means the gate could drop anywhere between 5 and 15 seconds.

When the card goes sideways I put the bike into second gear by clicking uo on the gear shif once. Then you turn the throttle about three fourths of the way and wait for the gate to drop. While im waiting I watch the pen that holds the gate up because it has to move before the gate drops.

Then when the gate drops you drop the clutch and hold it wide open. During this I don’t let out of the throttle until I get to the first corner. Once you get there you want to use your front and back brakes. The front brake stops a lot faster then the back so if you use it you can stay in the gas longer. If you use my tips you should be able to grab the holeshot and it will make your race results a lot better.