Motorcycle Forum

Motorcycle Forum (
-   Motocross Forum (
-   -   Why all the four stroke hate? Because... (

mscuddy 09-14-2009 03:51 PM

Why all the four stroke hate? Because...
I was bench racing with ol' Super Hunky the other day, and the topic of four stroke MX bikes came up again, and we both launched into several minutes of anti-4 striker tirades that included...Costs too much...blows up after a few scant hours of racing...costs too much...blows up, expensive to fix...costs too much...blows up, slow, blows up......etc....etc...etc..

Now don't get me wrong, I think these new Japanese four stroke 450's are the pinnacle of engineering and metallurgy, mixed with radical works design theory, and are quite the race bikes. But have they caused the sport of Dirt Bikes to shrink in size, and become just another ultra-expensive sport where only the well heeled can compete?

Take for instance the numbers: In 1973 over one million dirt bikes were sold in the USA. In 2009 that number shrunk to two hundred thousand, with ATVs out selling dirt bikes for the first time.

Not a good thing. We all know why the AMA and the big Japanese manufacturers changed to the four strokes, the environment. The tree huggers didn't want all those smoky seemingly unbreakable two strokes stinking up the landscape with Maxima Castor and Yamalube R, so they gave us ultra-trick four strokes that seem to get faster, and more prone to exploding with every new model year.

In our ranting Rick said something very poignant with regards to the new breed of four stroke dirt bike: Hell, we should love 'em, just because they are what they are; super tricked out factory racers that are filled with unbelievable technology.

But all that trickness comes at a price. And can that price be shutting the door on the average dirt biker? One who can't afford to purchase a new dirt bike for nine thousand dollars out the door, and then in 15 hours or so, sink another two grand into it for a new top end? And god forbid if the bike blows up, and takes out the entire motor. That runs around four grand to fix.

This is also why old CR500's and KX500's are bringing in top dollars for a decent used model. I got $1,200.00 for my ratsy '87 CR500, no haggling. And since I bought it in 1987 for $2,100.00 out the door, that's pretty damn good money for a 22 year old dirt bike.

So the sad fact is, the sport is shrinking, becoming more expensive, and specialized. You don't buy an MX bike anymore to play around on. And you don't take a play bike and manage to race it somehow. The time of the tinkerer and home taught bike mech is over, an era gone.

So long two stroke. It was fun.

pplassm 09-14-2009 07:24 PM

KTM, Husqvarna, and GasGas are keeping the 2 stroke alive, so far. And they still rule in Eastern events.

300EXC is still the most "balanced" bike out there, with and e-start, no less. I'd have one, but I'm a cheap bastard.

It's all good, if you ignore motocross!

I confess to owning 3 4 stroke dirt bikes to 1 2 stroke, but that's just economics. My 5250EXC has proved bullet proof. I just got my old DR350 back from my brother. A new piston and a little TLC, and it's ready to go. My DRZ 400s is still the bike I'd want, if I could only have one.

But, I hop on the CR500, and it's MAGIC! Amazing.

Sure, the new MX'ers may require a bit more attention than the old bikes, but I don't think that's the reason for a drop off in MX participation, if there is one. ( Still lots of MX participation out here on the right coast.)

There are lots of used bikes for sale at reasonable prices, as usual.

Is a "catastrophic" event more expensive? Yes. But the performance and rideability advantages may be worth it.

There are races/places where 2 strokes have an advantage, but MX is not one of them, any more. I am just about convinced that, unless the rider is James Stewart, a 2 stroke 450 will not beat a 4 stroke 450 on a motocross track. They're just too easy to ride, and the development of the 4 strokes is too advanced.

Are there inherent advantages to 2 strokes? Sure. But, until someone develops motorcycles that truly take adavantages of them, I consider them equal.

Choices. Difficult, but fun.

Curently looking for a cheap Husqvarna 360 (six speed) so I can stuff it in a modern chassis.

seruzawa 09-15-2009 05:24 AM

Well, the 4poppers only seem faster because they've eliminated the larger racing classes. The new 450s are faster than 250 2poppers but would still be easy meat for the 360 class smokers. It's all about perception and cooking the rules to make the manufacturers' current output look glamorous, no matter that they are in the end pathetic shadows of the dirt bikes of the past enginewise. No amount of hype can change reality. Now it may mainly be the fault of environmentalist pressures and we have no choice but to go to 4 strokes. Granted. Be that as it may it doesn't change the fact that it's destroying the sport and I have no desire of any kind to waste $ on these grenading wunderbikes. Nope. A New piston in the IT and I'm ready to go.

pplassm 09-15-2009 05:38 AM

I would really take issue with that. Current 450s make more power than MOST riders can use, and just about all find them easier to ride fast.

At amateur levels, 250 two strokes compete head to head with 250 four strokes. And still, the vast majority ride the diesels.

At pro level, sure, a large displacement 2 stroke might be faster. It would certainly be able to make more power, and be lighter.

Would it hook up as well, and actually be faster, though?

I love my CR500, but I have no delusions about its speed. Or mine, for that matter.

Of course, current two stroke technology is stagnant, except for KTM's off-road offerings.

BTW, I hear Dirt Rider published an article about a KTM300 based MXer making over 50 HP.

seruzawa 09-15-2009 05:42 AM

Well, we'll never know. 2smokes are dead and the publications are going to extol the new MXers, like they do all new bikes, because they want the advertising dollars. Truth doesn't matter. Only dollars.

Mikeee P 10-13-2009 12:02 PM

It's not a hp issue, the 2-stroke engine kills the 4 stroke in that area.

A 250cc 2str MX bike making 50hp -vs- a 250 4str making 38hp. Winner, "2 Stroke".

What does kill the 2 stroke is the tractability of that big thumper firing every "other" time so it's hooking up instead of spinning. That along with the heavier parts makes for a meaty powerband that's 3-4 times wider than that of a 2 stroke...

It come down to there is no replacement for displacement (in a sense). The 2 stroke can definately compete with the thumpers but they have to be on more equal ground. Eric Gorr (grandfather of the 125 big bore) has a new 300cc kit out for the YZ and RM250 that he says makes about 56-57 rwhp. Whoa... that's a lot. Then as someone mentioned the FMF KTM300 is making 54-55 with a quiet core insert in the muffler suddenly that 56/57 really is legit!

What is it like to ride? Is it wayyy to hard hitting, is it... dunno, never ridden one. But, they say that some of these 300cc bikes will outrun a 450 in rolling drag race. That's impressive...

I'd love to see more 2 strokes out there. They were simple to keep up, they were simple to modify... they were inexpensive! There needs to be more pressure to put 2 stroke classes back into local racing. Maybe the AMA could do a 250 four stroke, 450 four stroke and 250cc 2 stroke class. I'd love to see that at the Nationals... or maybe the 450cc class should be an "open class" allowing punched or bored/stroked 250cc motocross bikes in it up to say... 350cc? Suddenly the factories aren't doing all the work and little shops like Noleen, FMF, Pro Circuit would be building kits again for racers!

Maybe it'd help maybe it wouldn't but for me... there's nothing more impressive than a good running 450 four stroke... but there's nothing more FUN than a good running 2 stroke that'll darn near do the same thing for a WHOLE LOT LESS! *grin*

Mikeee P

Mikeee P 10-13-2009 12:08 PM

Regarding the big bores - I really wish they would have developed the CR and KX500 the way they should have. The manufactures started backing down after the 500cc class started getting stale...

If they had moved forward and used some of the info we have today like direct port injection, smokeless oils (snowmobiles) and just better porting theory... then suddenly the bikes would have taken on a whole new attitude. Easier to ride wider powerbands than 250cc bikes would have been awesome.

On the dyno a 450 thumper and 500cc two stroke look very similar, it's just that the 500 is revving a WHOLE lot quicker (steeper line) so it makes it more of a handful... with some development time they could have cured all those issues...

The KX500 in particular had so much more potential what with it's powervalved engine... but Kawasaki wasn't really interested in developing it so the old style non-PV engine of the CR500 was much more civil and decent to ride...

Could you imagine a CR/KX/RM/YZ in a modern 250cc chassis with about 400cc... sounds like a recipe for fun!

mscuddy 10-14-2009 03:26 PM

1 Attachment(s)
Or a Maico 660...

pplassm 10-15-2009 03:37 AM

Stupid MO won't let me see the picture. Got a link Cuddy?

All times are GMT -7. The time now is 01:44 PM.