Nathan "I thought you knew everything"? The swish is the shape of the head (combustion chamber). It was common to change this shape when we were forced to use unleaded fuel.
I don't know why they don't just introduce a 250 2st class. The cynic in assumes that it's probably because the manufacturers will sell less 250F's....
I don't know why they don't just introduce a 250 2st class. The cynic in assumes that it's probably because the manufacturers will sell less 250F's....
If you have ever had anything to do with running a current National rounds you will know that there isn't room for any more classes without going to two day meetings.
Also a well tuned std 250 2 stroke will still be a match for a 250 4 stroke (even the worked ones). But a 4 stroke is easier to ride so the four stroke can still match the 2 stroke over the full race distance. Also the privateers will still choose the 2 strokes unless they are aligned with a manufacturer who doesn't sell them now.
I don't know why they don't just introduce a 250 2st class. The cynic in assumes that it's probably because the manufacturers will sell less 250F's....
If you have ever had anything to do with running a current National rounds you will know that there isn't room for any more classes without going to two day meetings.
Also a well tuned std 250 2 stroke will still be a match for a 250 4 stroke (even the worked ones). But a 4 stroke is easier to ride so the four stroke can still match the 2 stroke over the full race distance. Also the privateers will still choose the 2 strokes unless they are aligned with a manufacturer who doesn't sell them now.
I have had a bit to do with modern MX while you ask.....and yes, there is plenty of room for another class UNLESS the same 4ST riders want to compete on the 2 smokes as well
If I read the rules right, and I must admit it was only a quick read, in MX1 there is nothing stopping you riding a 255cc or larger two stroke.
So you could put a 500cc two stroke engine in a 450f frame and race against the 450 four strokes?
Is this right or did I not read far enough down the page??
If I read the rules right, and I must admit it was only a quick read, in MX1 there is nothing stopping you riding a 255cc or larger two stroke.
So you could put a 500cc two stroke engine in a 450f frame and race against the 450 four strokes?
Is this right or did I not read far enough down the page??
i think that's the way of it Nathan, the big four have gone green with 4 banger push from the 1990's and not much will bring them back other than real smack in the face sales figures. kato and husky etc with their 2 bangers have that sown up....The manufacturers would like us to think the 4 t push is for the enviroment, but it's B.S.
Reads MX1 class 255cc and over, no limit.If I read the rules right, and I must admit it was only a quick read, in MX1 there is nothing stopping you riding a 255cc or larger two stroke.
So you could put a 500cc two stroke engine in a 450f frame and race against the 450 four strokes?
Is this right or did I not read far enough down the page??
No you read it wrong. The upper limit in the Aust MX & SX Championships 450cc. So a 500cc 2 stroke is too big and anyway the last of the 500cc 2 strokes were too powerful. The last 2 stroke to win a 500cc World Championship was a 360 KTM. So something around 400cc would work.
Reads MX1 class 255cc and over, no limit.If I read the rules right, and I must admit it was only a quick read, in MX1 there is nothing stopping you riding a 255cc or larger two stroke.
So you could put a 500cc two stroke engine in a 450f frame and race against the 450 four strokes?
Is this right or did I not read far enough down the page??
No you read it wrong. The upper limit in the Aust MX & SX Championships 450cc. So a 500cc 2 stroke is too big and anyway the last of the 500cc 2 strokes were too powerful. The last 2 stroke to win a 500cc World Championship was a 360 KTM. So something around 400cc would work.
SX1 has 450 limit
i think that's the way of it Nathan, the big four have gone green with 4 banger push from the 1990's and not much will bring them back other than real smack in the face sales figures. kato and husky etc with their 2 bangers have that sown up....The manufacturers would like us to think the 4 t push is for the enviroment, but it's B.S.
The real reason is the spare parts gravy train and regular( annual or bi annual) bike up grades required for the four stroke racer.
Husky 430AE with a bit of a diet... Made em more than 25 years ago.....not to mention the built in "throw away" life span of them.
I'm told that a 4T MX bike is very emissions unfriendly when you look at the entire range of gases is spits out - that its in the same league as a 2T MXer (slightly better, but not the comprehensive victory to the 4T that most people assume). Love to have that verified or disproven.
We even got a new pollutant in motocross thanks to them.....NOISE. And that one is what is causing the most damage to our sport. Where's the manufacturers responsibility here?
Even KTM seem not willing to develop their 2 strokes just small changes. I'm hoping that the new 300 cc two stroke class at the GP's will start getting some factory attention.
We need the new generation to have fuel injection and electronic controls. Please give me a two stroke 400cc 55 HP auto gearbox 100 KG bike before I die.
Only real 2T engine development now is with superkarts. Check out Modena engines or Roland Holzer on fb
Noise isn't a new pollutant the four strokes have just perfected it.
The manufacturers are the ones to blame.
Even right from the word go the 4 strokes were louder. When they were first introduced a standard 4 stroke was 102 DBA and the 2 stroke was 98 DBA.
Even now they cheat. They retard the spark in neutral so when you do a noise test it is quieter than when it is running on the track. It is time to get serious. Make the manufacturers make them quieter and make the riders run the standard mufflers, for two and four stroke. The so called performance exhausts that are sold in Australia just make more noise.
Also the sound from four strokes carries further than two strokes. Fog horns put out a lower note for a reason because it carries further.
Only real 2T engine development now is with superkarts. Check out Modena engines or Roland Holzer on fb
There is a lot of progress in 2t outboard motors as far as emission and fuel injection goes...
The stig
I very much doubt KTM has an injected 300. Most adventure bikes now are injected with good reliablity and they were mapped badly and erratic when first released but that's in the past.
At the Conondale Cup just run yesterday, Yamaha rider Jay Wilson rode a 2015 YZ 250 2/- in the Open All Powers and a YZ 250F in the 250 class. He said he did it to prove that the 250 2/- should be in the 450 class.
The problem is that if the 2Ts are regularly winning then at least Honda/Kawasaki/Suzuki (and probably Yamaha) will probably simply withdraw their support.Probably.. And its that kind of pressure from the factories that killed the 2t in the first place
This is a bad outcome for WEM, so he'll do whatever it takes to keep them happy.
The Jap manufacturers don't want 250 2t's beating their 250f's because they either don't sell them or have pumped all their development into 4 strokes.
The privateers love them because they can afford to race the series without a major sponsor or rich daddy.. The result is competitive privateers and big fields in the 250 class.
The promoter should leave the rules as they are and eventually the Japs will have to start producing new 250 2t's again if they want to keep winning..
The problem is that if the 2Ts are regularly winning then at least Honda/Kawasaki/Suzuki (and probably Yamaha) will probably simply withdraw their support.
This is a bad outcome for WEM, so he'll do whatever it takes to keep them happy.
I very much doubt KTM has an injected 300. Most adventure bikes now are injected with good reliablity and they were mapped badly and erratic when first released but that's in the past.
Various reports from KTM say that they have a direct injected 2T that is pretty much ready to go, but it makes the whole bike as heavy and complex (and presumably as unreliable) as a 4T, so there's little point.
In the USA though you might still be able to buy a two stroke in California, you are limited to when and where you can ride them, and it looks like you have to 'register' them.Ever been to L.A. the polution is discusting? I can see where the 4t push comes from.
So if the manufacturers still see California as one of their biggest market sales areas, they may be reluctant to go back to developing anything 2t.
And don't forget that Australia's sales market usually doesn't factor much into Japanese overall sales considerations.
Web page for California regulations:
http://www.arb.ca.gov/msprog/offroad/ofhwymc.htm (http://www.arb.ca.gov/msprog/offroad/ofhwymc.htm)