Skip to Content

250cc Motocross Bike: 2 Stroke vs 4 Stroke?

If you’re looking to get into racing motocross at AMA sanctioned tracks and are wondering which bike to buy for the 250cc class, then pay attention.

250cc 2-stroke vs. 250cc 4-stroke

Although the four-strokes have pretty much taken over the motocross market, it seems that there are a lot of people trying to bring back the two-strokes, and it seems to be working.

AMA made it legal so that a 250cc two-stroke can run in the same class as a 250cc four-stroke. Now, the first reaction I had when I heard of this was without doubt to pick the two-stroke. I looked into it a little bit more and came up with this….

250cc Four-Stroke

Most people would think that a four stroke with the same displacement as a two-stroke would not have a chance, and that is why the AMA originally allowed the four strokes to run a bigger engine in 1998.

2010 Yamaha YZ250F 250cc Motocross Bike: 2 Stroke vs 4 Stroke?
Yamaha YZ250F

This isn’t the case, due to the fact that companies have put so much more money and effort into making the modern four-strokes extremely high-performance. Some riders that do not like the two-strokes snappy power will often stick to the four-stroke 250 just because they like their broad and easy-to-ride power-band.

A 250 two-stroke may have more peak power, but when the day gets long and the track starts to get really rough, that’s when the four-stroke starts to shine. Due to the tractability in rough and slick conditions, the four-stroke will be easier to ride faster late in the day. That doesn’t mean it will be faster than a two-stroke though…

250cc Two-Stroke

Two-strokes are fun to ride because they have a bigger top-end “hit” compared to the four-stroke. If you keep the two-stroke on the pipe then it will definitely be faster than the 250F, as long as the conditions aren’t too rough.

2012 Yamaha YZ250 250cc Motocross Bike: 2 Stroke vs 4 Stroke?
YZ250 2-Stroke

For those of you that want more, snappy power, and a lower center of gravity, then go with the two-stroke. It may not always have the traction that a four-stroke has in rough or slick track conditions, but the horsepower makes up for it.

So Which Bike??

After reading the info on each bike you would probably guess that the two-stroke is the better bike for AMA racing, and my answer for that would be, “Yes.” Clearly, it’s a faster bike if the track is in good shape, it handles better because it has a lower center of gravity and is a 2 stroke, it has a lighter front-end allowing you to skim over whoops and bumps, and it smells good.

But I will say that if you are a four-stroke guy that doesn’t like the snappy-feeling power-band on the two-stroke, then you will be fine on a 250F. The 250F is by no means slow, and any good rider should be able to win on it. My choice would be to ride the 250 two-stroke though because it’s faster, and it’s a new rule that I would take advantage of. Good luck, and no matter what stroke you ride, have fun!!


Sunday 18th of December 2022

I had a few two-strokes in the 70s. My favorite was a tricked out Suzuki RM250. I forget the year, but it was before mono-shock. Had the FMF pipe, was ported & polished, bigger carb, etc. I could run even with my friend's mostly stock RM370 (before the 400 came out). My parents would not let me race, but had a ton of fun anyway. I had bottles of Belray premix oil stashed at various gas stations around town.

Kelley Fager

Monday 19th of December 2022

Sounds like you miss it, John - thanks for sharing!

ed henton

Sunday 10th of April 2022

Raced Suzuki 125 and 250 RMs back in the'70s and early '80s. Now I may be a healthy young-minded senior on social security today, but let me tell you that to this very day the sound and smell of a two-stroke in the morning air still gets me hard as a rock. If you were there then you know what I am saying, it becomes part of you for the rest of your life.

Kelley Fager

Monday 11th of April 2022

Ha, I totally hear ya, Ed! I think my favorite smelling dirt bike was my KX125 with race gas and castor oil. Thanks for reading and commenting!