Displacement in moto

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6/8/2018 5:12 PM

Hello. This forum is full of great and wonderful moto fans. I don't know anything about the bikes and I'm genuinely curious about this so if someone could answer in detail so I understand that would be fabulous.

It is my understanding that 250cc two strokes can't race in the 250F nationals. Why is that? Do the 250 two strokes make way more HP and are faster with the same displacement? I don't understand why only a 125cc bike with smaller displacement is the only two stroke allowed to race with the 250F and a 250cc two stroke with the 450Fs.

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6/8/2018 5:14 PM

In

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Braaapin' aint easy.

6/8/2018 6:19 PM

Okay, I'll bite.

Double displacement allowed to progress 4 stroke machines, which until recent history (20 years ago) were heavy and slow. Now they have as much or more HP than their 2 stroke cc equivalent, yet the rules still stand. The engines are easier to ride fast as they can rev much higher and make power over a very wide range, chassis and suspension tech at the stock level are now on par with the engines.

What this translates into is faster riding and racing = progression. The 250 class today probably going as fast as the 250 class was 20 years ago. 450 class with easy to ride engines can utalize the power on good chassis like the 500 class never could.

Just like anything else it is hard to take a step backwards. The 250 class people are staying longer and longer (often with more competition) because it's really two classes running side by side. Compare the lap times, often similar between the two classes except for certain tracks where the additional hp of a 450 can be used.

250 class is no longer a feeder class, and should be treated as such. The 125cc professional racing class should be re-established as the feeder class. CC for CC racing should be allowed in both 250 and 450 or "open" premiere classes.

However, this will never happen. The "powers that be" are too ignorant, lazy, and blind to what is coming. The future of the internal combustion engine is in jeopardy and electric is the future. The early adopters of the mx population thinks of all of the positives and none of the negatives, similar to the 4 stroke takeover.

You can buy a Razor "motocross" bike in Walmart right now for less than $300, no huge wave of young riders...As soon as the ICE is phased out the actual sport will die off soon after.

The "powers that be" don't have the courage to introduce 125 feeder, 250 cc for cc premier, 450 or "open" cc for cc premier racing classes. They will give you bureaucratic excuses for their short-sighted self-serving agenda. Passing blame from one abysmal organization to another, all of whom throwing their hands up saying "nothing we could do".

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6/8/2018 6:22 PM

Quick answer is: Honda does not make 125 & 250 2 strokes.

Next question....

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6/8/2018 7:45 PM
Edited Date/Time: 6/8/2018 7:46 PM

The rules definitely need to be revisited or it will IMPLODE. Wake up oem's.

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6/8/2018 8:38 PM

peltier626 wrote:

The rules definitely need to be revisited or it will IMPLODE. Wake up oem's.

Why change the rules now when e-bikes are just around the corner.

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Ride like a girl!!!
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6/8/2018 8:41 PM

mb wrote:

Okay, I'll bite.

Double displacement allowed to progress 4 stroke machines, which until recent history (20 years ago) were heavy and slow. Now they have as much or more HP than their 2 stroke cc equivalent, yet the rules still stand. The engines are easier to ride fast as they can rev much higher and make power over a very wide range, chassis and suspension tech at the stock level are now on par with the engines.

What this translates into is faster riding and racing = progression. The 250 class today probably going as fast as the 250 class was 20 years ago. 450 class with easy to ride engines can utalize the power on good chassis like the 500 class never could.

Just like anything else it is hard to take a step backwards. The 250 class people are staying longer and longer (often with more competition) because it's really two classes running side by side. Compare the lap times, often similar between the two classes except for certain tracks where the additional hp of a 450 can be used.

250 class is no longer a feeder class, and should be treated as such. The 125cc professional racing class should be re-established as the feeder class. CC for CC racing should be allowed in both 250 and 450 or "open" premiere classes.

However, this will never happen. The "powers that be" are too ignorant, lazy, and blind to what is coming. The future of the internal combustion engine is in jeopardy and electric is the future. The early adopters of the mx population thinks of all of the positives and none of the negatives, similar to the 4 stroke takeover.

You can buy a Razor "motocross" bike in Walmart right now for less than $300, no huge wave of young riders...As soon as the ICE is phased out the actual sport will die off soon after.

The "powers that be" don't have the courage to introduce 125 feeder, 250 cc for cc premier, 450 or "open" cc for cc premier racing classes. They will give you bureaucratic excuses for their short-sighted self-serving agenda. Passing blame from one abysmal organization to another, all of whom throwing their hands up saying "nothing we could do".

Great answer as far as rule wise or industry wise why it happened and where we are at today but I'm curious if... well I alwyas thought displacement wise they won't like 250cc two stroke vs 250F four stroke in the same race cause some how the 250cc two stroke would have the advantage and the manufacturers don't want people to see that.

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6/8/2018 9:45 PM

peltier626 wrote:

The rules definitely need to be revisited or it will IMPLODE. Wake up oem's.

queen of spodes wrote:

Why change the rules now when e-bikes are just around the corner.

I don't know what around the corner means but it's not like it's hard to change rules is it?

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6/10/2018 2:17 PM

The four-stroke is NOT a better machine, they are just given an enormous displacement advantage.

Everyone knew it was a problem 10 years ago. I always like to offer a solution, and not just bitch. The Pirelli Auto Racing Series uses a "Balance of Performance" initiative, where they add weight, reduce RPM, almost weekly to keep various automobiles competitive. Why not make 450cc bikes use a 30lb skid plate? If we're worried about the manufacturers saying changing cc's is too expensive, then add weight.

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6/10/2018 2:41 PM

Th Big 4 OEM's don't want to make 2 strokes.... simple as that. And they are killing the sport.

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