is it true?

awhile ago I heard that the ama was going to let twostrokes get bored to 144cc and race against 4strokes in the 125 this true? is it going to take place soon

Hell the people riding the 4-strokes probably have their bikes bored out why shouldn't the 2-stroke guys. At our tracks you can have a 85 bored to a max of 105 and it's still legal to do it.

Only in the amateur ranks from what I understand.

It is true, but not for all of the Loretta's classes and not for AMA Pro racing. It looks like GNCC will also be allowing it this year, from my understanding.


I heard from like Transworld i think, in a article that soon the AMA will allow the 2-strokes run up to the same CC's as the competitor 4 stroke. ex: a two stroke that is bored out to 165 will still be able to race the 250f's. The 4 strokes are not gonna be able to be bored out. What does everyone think of that? If that goes into play the 2-strokes will be the kings once again.

There will be no chance of this happening. The factories controll the AMA. The factories will not allow their 4 stroke development money to be flushed down the toilet. The two strokes being allowed the same displacement would do this.

The 144 rule? Guess who helped them with this decision? Weisco. Guess who stands to benefit a great deal once we all need big bore kits to compete???

Wiseco is not the only company that helped with this decision, yes they will benefit but so will everyone else that makes MX parts (It was a board decision by the way). The point behind the decision was to give local guys a fighting chance on a 2-stroke, not to make money for any particular company. The performance of the 250F has pretty much rendered the 125 useless (aka no value). Now a guy can pick up a relatively cheap bike and have some work done (not much more money than having it ported or replated) and be competetive in the "Lites" class.

The best thing this rule change does is that it gives a guy (or girl) a competetive choice on what bike they want to ride.


The 2-stroke ATV's in the limited cc classes can go to the last bore on their cylinder. The 250R's can go to a 265 which is the last bore. The 4-strokes have to stay at 450cc. The 4-stroke cylinders aren't borable. If the 2-stroke bikes were able to do this the factories would have to use borable cylinders in the bikes. I heard that the 2-strokes weren't supposed to be around past 2007 in AMA sactioned races. If that is true, I don't see why they would even bother with it.

In the bikes you can go to 144cc even if the bike came with nikasil (non-borable). You just bore it out and have it replated.


what would be the maximum you could bore a 2 stroke 250 out to if you still wanted to stay in the 250 2 stroke/450 4stroke class

I would guess 285cc.

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