Two-strokes set to continue at MX Nationals in 2015 (not VMX)

[Slakewell]

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.

[Nathan S]

Husky 430AE with a bit of a diet... Made em more than 25 years ago...

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.

[evo550]

Husky 430AE with a bit of a diet... Made em more than 25 years ago...

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.

..not to mention the built in "throw away" life span of them.

[Nathan S]

I know of three CRF250s that have blown big ends under 50 hours.
Buggers the cases too, of course.

[80-85 husky]

Servicing them by the books is expensive and if you are racing, they need that level of servicing. they will go a long way without servicing under normal riding conditions but to stay at the pointy end of competition, you just cant afford not to spend the $$

compared to an 86 XR or TT the new 4t's are awesome!! but there are XR and TT's that are still running with minimal work other than oil and filters and occasional valve checks.

blow up a twoie and for the cost of a couple of 4t services, you can renew the entire engine!

[Slakewell]

The YZ gets new plastic this year. I wonder if it retro fits my 09 model

[Nathan S]

Yes it does. I think the new version looks awful - lamb dressed up as mutton dressing up as lamb.

[yamaico]

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?

Dead right Davey. I have lived at the base of Mt Kembla for over twenty years and in the days before those shitbox self destructing four strokes came along the only way you knew that there was a race meeting on at the old Mt Kembla track was you could see a bit of dust in the air. Now you get that bloody drone, that will eventually see the end of the track. I've got some land not far away where I'm going to live when I get my house built where I've got enough room for a small track but, apart from XR75's and a couple of posties, there won't be a single 4T there, that's for sure.

[KTM47]

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.

[80-85 husky]

up near my last house was a popular riding area...all weekend blllaaaat brraaaap bloody 4strokes... once in a blue moon you might hear a twoie if the wind was blowing in the right direction, seriously quieter than pooh bangers.

when I was racing the 2000 kato 250 2/, it was called the stealth bomber as it was so quiet, the 450 riders didn't know I was there till they saw my front wheel on the inside as I passed em. it was box stock in the muffler, just repacked with steel wool.

[KTM47]

Severals year ago (around the time the YZ400F was introduced), the old bastard who lived over the back at Tivoli Raceway (He's gone now RIP Lenny).

Anyway he told me the noise has become worse over the past few months.  I didn't tell him why.  Bloody modern four stroke (the older ones aren't as bad).

He also didn't like commentators who did Darryl Eastlake impersonations.  We had one commentator who shouted into the mic.  But everyone likes it he would say. Well I f@#$en don't and I can't understand you.

Anyway noise and dust are the two biggest problems MX has.

[KTM47]

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.

Apparently KTM have been developing their 2 strokes and by default Husqvarna.  That is what has created the problem.  With the KTMs etc getting better and faster riders willing to race them they have started to dominate the 4 strokes.  Yes I know a 4 stroke won, but apparently they have to spend a lot to do that.

Also the Yamaha 2 strokes can't match the KTMs etc.  You only have to look at KTM's 65s and 85s too see they are better. Kawasaki has improved their 85 but that is about it.

So really it is better if KTM don't make them any better.  They will be cheaper to run that way.

So long live the 2 stroke and welcome back.  Too all you 4 stroke riders learn to ride harder and stop whinging 

[Lozza]

Only real 2T engine development now is with superkarts.  Check out Modena engines or Roland Holzer on fb

[the stig]

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

[KTM47]

Hopefully someone can develop them enough to get them back into the Californian market.  That is where the problem started and the 4 stroke took hold.