Once again, because it's worth repeating

[Coop]

When you have the best racers in the world, on the best machines that money can supply and put them up against a journeyman Pro with some work done to his bike, you really start to see the advantages of displacement.

http://www.mxlarge.com/interview/2821-david-bailey-rick-johnson-and-johnny-o-mara-look-back-at-1986-maggiora-mx-of-nations

[scotty dog]

Didnt RC give everts a riding lesson at an MXdN? Was it 05? RC was on a CR 250, Everts was on his YZ 450. I might have the year wrong but i remember seeing the pics a while back....

Remember Pastrana at the nations with his mighty 125???

Yeah i do now!! HUGE down hill jumps over some French guy if i remember.

[2smoker]

The only way to get the 2 stroke back on the tracks is to eliminate the 4 stroke! The manufacturers won't produce or R&D both. This is why AMA won't change the rules at pro level because they know it can happens. The sport is doomed.

This makes me smile

Jeremy McGrath Terrafirma 2

[JETZcorp]

It seems I'm a little late to this particular party, but when we were talking about making an equal-displacement four-stroke match the power of a two-stroke, I know it can be done.  For example, if you take Maico's claimed HP for their 500 (I'm using that number just because I have it memorized) the ratio of power to displacement is 134hp/L.  But if you take a BMW S1000RR, that gives you 179 hp/L.  Granted, that's a multi-cylinder engine so that's probably helping things out a bit for the Beamer.

But what we should remember is that the Beamer, even with multiple cylinders, has to rev way over 13 grand to make that kind of power, whilst the Maico is doing it at something like 8k.  Also, brand loyalty aside, that's not exactly the craziest two-stroke available, it just happens to be a dirt bike that I knew the numbers for.  Let's see what kind of power a four-cylinder two-stroke sport-bike motor would be like.  Oh hey, looks like somebody (Suter Racing) have just that, and it's got 20hp more than the Beamer... and half the displacement.

Is it possible to make an ultimate four-stroke more powerful per unit displacement than a two-stroke?  Does that mean it has more potential?  Hell no.  Now what I'd like is to see what would happen if you gave someone like Don Garlits 20 years to make the best top-fuel drag racing two-stroke he could.  If the four-strokes are making 8,000hp now...

[JohnN]

The only way to get the 2 stroke back on the tracks is to eliminate the 4 stroke!

How can we do that???^^^^^^^

If you have a constructive idea, we should all be working towards that goal. The problem is that the manufacturers that we want to build two-stroke bikes for us are firmly entrenched in the four-stroke way of MX....

[ktm150rippa]

what I have noticed in mx is it really is all the rider I know at the pro level it really does matter what bike your on I think us 2t riders really have to change the way we think. Like if your racing a two stroke you should almost never take the same line as a 4 we kind of have to hang it out there hold the gas on longer make some moves maybe we're not exactly comfortable making but when your at a disadvantage you gotta do it. I imagine you have to ride like ryan villopoto was on the clip some1 just posted of him on that 85 you could tell he didnt want that 250 getting around him chewin through gears, switching lines puttin his butt way over the back fender. You really just have to ride a 2t like you are pissed off at it

[JETZcorp]

Yeah, I think in any situation where you're at a power disadvantage, you have to be able to carry speed rather than generating speed.  Because if you play the game of generating speed, the other guy who has the hardware to generate more speed is going to win.  But if you can keep it screaming, hammer it through the corners and come out with a big exit speed, you can make up some of the gap.  That was the advice given to 430 Husky riders when the wave of 490s hit, so I don't know if it applies so well to the current situation, but I think it should.  That was a situation where you had a horsepower bike competing against torque bikes, and that sounds like today's 4T handicap to me.

[Super Trucker]

The only way to get the 2 stroke back on the tracks is to eliminate the 4 stroke! The manufacturers won't produce or R&D both. This is why AMA won't change the rules at pro level because they know it can happens. The sport is doomed.

This makes me smile

Jeremy McGrath Terrafirma 2

    That  video is awesome I  watched  it  countless times years ago. The  most fun era in mx in my opinion, my  friends  and I  trying  to pull off tricks  in our races, alot  of laughs. Mc Grath  races  off road  trucks  now, for  Johny Greaves-Monster team. Johny  lives  20 minutes  north  of  Green Bay,he  has  another  house in Cali. They  ride mx together along  with  John,s 16 yr. old kid. Before  and after  the truck season,John an  x pro  mx,r  races  mx, I,m  Looking  forward  to  racing him. I  didn,t  realize  I  put  too  much space in  between, I  just  figured  it,s  easier  to read, I,m  43  you  know what  they say,your  eyes  are  the 1st thing  to go.

[TMKIWI]

I thought it was the mind 

[Super Trucker]

What,s  a  mind ? haha

[reefmuncher]

It seems I'm a little late to this particular party, but when we were talking about making an equal-displacement four-stroke match the power of a two-stroke, I know it can be done.  For example, if you take Maico's claimed HP for their 500 (I'm using that number just because I have it memorized) the ratio of power to displacement is 134hp/L.  But if you take a BMW S1000RR, that gives you 179 hp/L.  Granted, that's a multi-cylinder engine so that's probably helping things out a bit for the Beamer.

I don't think using that comparison is very fair as it's comparing apples with oranges! The BMW is a super oversquare maximum horsepower multicylinder road machine with each cylinder displacing 250cc. To be fair it would be better to compare to an equivalent high performance road tuned 4 cylinder twostroke with 250cc cylinders which doesn't exist and if it did would probably be detuned just to be rideable. Closest I can see is the RS500GP twin which is 130hp or 260hp per litre.

If you did that then for 500cc the BMW would be 90hp vs the 130hp of the RS500GP or as 250's would be 45hp vs 65hp.

I don't think when it comes to churning out horsepower equal cc fourstrokes could ever compete without some form of blown induction. To even try to do so would just be a futile and pointlessly expensive exercise.

[JETZcorp]

I never said it was rideable, just possible to make a four-stroke of some kind with more power per unit displacement than a current two-stroke motocross bike.  Now whether it would be faster or practical is an entirely different matter, and goes to show further that four-strokes just have too much to make up for.  Besides, all the 4T dirt bikes that are being sold are massively oversquare, too.  That's how they can rev as high as the BMW (for a time).