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Clubroom => General Discussion => Topic started by: mx250 on August 05, 2009, 07:44:26 pm

Title: 2T vs 4T
Post by: mx250 on August 05, 2009, 07:44:26 pm
http://twostrokemotocross.com/2008/08/yz250-vs-yzf250-by-mxa/

Here's an interesting article that directly compares to two stroke and four stroke Yammies. Well I found it interesting..... ::) :P ;D
Title: Re: 2T vs 4T
Post by: oldyzman on August 05, 2009, 08:24:56 pm
Interesting read, nothing sounds, smells or gets the adrenalin pumping like a twostroke... But a four stroke is great for mono's
Brett
Title: Re: 2T vs 4T
Post by: motomaniac on August 05, 2009, 09:05:16 pm
Interesting read, nothing sounds, smells or gets the adrenalin pumping like a twostroke... But a four stroke is great for mono's
Brett
Yer but a few years back people were saying that theres nothing like the sound of a bunch of 4 strokes roaring off the start line. Funny how time changes things.
Title: Re: 2T vs 4T
Post by: TooFastTim on August 05, 2009, 09:23:22 pm
Yer but a few years back people were saying that theres nothing like the sound of a bunch of 4 strokes roaring off the start line. Funny how time changes things.

True dat!
Title: Re: 2T vs 4T
Post by: vandy010 on August 05, 2009, 09:25:50 pm
i love em both. 2 stroke VMX bikes have more character of sound i reckon. but thats me being fussy...
Title: Re: 2T vs 4T
Post by: NR555 on August 05, 2009, 10:11:23 pm
It's what you're used to.  I used to go watch speedway every week, and never thought twice about the smell.  Now I need a hit of it every year or so!

There used to be an element of 'underdog' with four strokes, as they were mostly glorified enduro bikes for a while.  People would automatically gravitate towards them if they were in a race, just because they were different; and especially if they were doing well. 

The Thumper Nats was interesting, because we got to see whole grids of these weird & wacky bikes, with pro motocrossers well out of their comfort zones riding these big bad hunks of metal.  I had the opportunity of riding Stefan Merriman's TT600 Belgarda thumper nats bike for a day in '97.  That thing was tuned off its head.  I don't think I've ever ridden something so powerful.  That was all great until you tried to jump the thing or make a tight turn.  You could turn the QE2 quicker!  A real challenge for the rider.

When the purpose built YZ400F came along, it basically killed the concept stone dead.  It wasn't a modified trail or enduro bike.  It was built to destroy 250 2-stroke motocrossers!

Now we've gone full circle, and we find the two stroke guy the underdog, and a lot of people are totally over the farty four stroke sound we have today....  ;D
Title: Re: 2T vs 4T
Post by: Lozza on August 05, 2009, 11:45:53 pm
There was actualy an interesting bit in there when they (strangely) said the 2T could be thrown in at any angle on any line where as the 4T had to ride precisely and on the 'correct' line, everyone line astern. Which is oddly what seems to have happened in MotoGP.
Mind you NR it had to be a 400 to try to kill off the mighty 250, would agree with your thoughts on the Thumper Nats as that was just a great avenue for home tuners and bike shops to compete on similar budgets, but with the 450F's it's safely back in the factories hands. NZ was suposed to be running a 250cc class run what you brung but haven't heard how it's gone so far.
Title: Re: 2T vs 4T
Post by: mx250 on August 06, 2009, 05:57:07 am
Interesting read, nothing sounds, smells or gets the adrenalin pumping like a twostroke... But a four stroke is great for mono's
Brett
Hmmm, I both love and hate the sound of a 2t. I love the attention grabbing 'urgency' as they 'come on to the pipe', I hate them on the overrun popping and wheezing, I hate the 'ring-dinga-ding' of the typical warm up, and I hate them as the 'hunt' on a steady throttle.

Sound is one comparison I will concede to the 4T :-X ::)
Title: Re: 2T vs 4T
Post by: AjayVMX on August 06, 2009, 07:50:03 am
They say it all in the first few lines...  without the rule changes, 4 strokes wouldn't get a look in.

All that crap they write in trying to NOT make the 250F sound completely inferior, like how less power can be better for lower lap times, applies to 125cc (or for that matter 200cc) 2 strokes.

And let's not miss the really important point - the ease and cost of maintenance.  Not even close really...

Ah, what would today's younger generation think if they got to ride something truly awesome... like a KX500 or CR500 for example.  ;)
Title: Re: 2T vs 4T
Post by: ba-02-xr on August 06, 2009, 08:26:07 am
Its funny u say that Ajay. A while ago I let a 14 year old student of mine ride a KTM 500. They rode up the dirt rode & came back with a masive smile. Raved how much power & fun. I told them to do a couple of laps of the MX track & got a dumb look  & a coment along the lines of get stuffed. Thats an animal.
Title: Re: 2T vs 4T
Post by: allan hughes on August 06, 2009, 09:42:23 am
THE RAPID ACCELARATION OF 2T IS FUN
MODERN 4T THE NOISE IS A PROBLEM
THEY PASS THE STATIC NOISE TEST
WHEN HELD TO THE REV LIMITER
THEY ECHO FOR MILES
NOISE IS THE REASON FOR TRACK CLOSURES IN S/E QLD     
Title: Re: 2T vs 4T
Post by: AjayVMX on August 06, 2009, 04:51:49 pm
Yes, noise is also a big negative for the modern 4T brigade.  No-one seems to be able to leave the stock mufflers in place, they all seems to want to go out and spend megabucks on louder (and sometimes less powerful) Titanium items.... ::)
Title: Re: 2T vs 4T
Post by: LWC82PE on August 06, 2009, 05:29:23 pm
theres been a fair bit of discussion on this on endurobiketalk.com. we reckon theres going to be a resurgance in 2 strokes and possibly lower maintenance, longer lasting 4 strokes similar to XR400 or like the early long stroke water cooled 4 strokes.
Title: Re: 2T vs 4T
Post by: Lozza on August 06, 2009, 05:38:17 pm
There was a bit in a magazine recently actually advocating a 2T for the weekend trailrider........a long while since that's happened
Title: Re: 2T vs 4T
Post by: LWC82PE on August 06, 2009, 06:17:41 pm
was that in this months ADB? there was a 2T/4T comparison in the july or august ADB.
Title: Re: 2T vs 4T
Post by: Freakshow on August 07, 2009, 12:26:06 pm
I bought a 07 250 F after everyone toed the how good they were line, worst mistake i ever did - noisy as stock, cost shitful to run and maintain and gutless as all shit.

I still looking for a well priced 2 ee, petrol spark and never look back.  Problem is then only come up S/h rarely now as allus dumb arses bought the 4 banger,  all the guys i know race modern are saying if this 2010 YZf dont cut it in the new frame there going back to the 2 smokers.  I hope so i need to pick up a 1 season old speclail before i go mental.
Title: Re: 2T vs 4T
Post by: maicomc490t on August 07, 2009, 12:42:19 pm
For my money 2T

My 06 250EXC (in my mind) shits all over the F that I still have, and given that my not so little ' boy' wants to go trail riding that will be swapped soon for another Kato.

A friends not so techno son has a new 450 yellow bike and I reckon I'll hear the anguished cries at my place when his 'maintenance' schedule is forgotten and the top end lets go!

Dave Mac  :D
Title: Re: 2T vs 4T
Post by: motomaniac on August 07, 2009, 01:07:50 pm
New FIM rules coming .juniors ride 85cc 2stk , 125cc 2stk to keep it affordable. 250 class is 250 class 2stk or 4 strk etcetc.
The 4stk thing started with the Californian clean air act about 20 years ago.
MXA quote" an XR400 winning a superx race" ??? Then the yz400f got concession to race in the 250 class ,since 500 class was no longer in existance in the US .(and nearly dissappeared in Euro.Joel Smets went door knocking to save it)
The Euro's followed the example in the US and put big bore 4 stk with the 250 2 stk but the Euros are taking the inititive back.
Keep watching .In the meantime I think I'll take my beloved 94 CR250 out to hunt down some 4 bangers at our local.
Title: Re: 2T vs 4T
Post by: vmx42 on August 07, 2009, 01:13:34 pm
The funny thing about the 4 strokes and the Clean Air act is that I have never seen an emissions test for a modern 4 stroke MXer. They can't police the noise problem so they would have no chance with the emissions issue.

I would have a sly bet that they wouldn't go within cooee of passing [any more than a comparable 2 stroke].

And then when you add up the additional emissions made during the construction of all the extra parts required and it all looks like a bit of a marketing crock [and a political stunt to blind the naive electorate].

Not that I am old an cynical or anything like that… heaven forbid!!!
VMX42
Title: Re: 2T vs 4T
Post by: motomaniac on August 07, 2009, 01:42:59 pm
"And then when you add up the additional emissions made during the construction of all the extra parts required and it all looks like a bit of a marketing crock [and a political stunt to blind the naive electorate"

My argument exactly - the emmissions made during the construction of "a new greener car" is never factored in and it would take years to get the real benifits if it was.Industry is the biggest green emisions producer.

but they do do emmisions tests in California but not on bikes for competition only.In fact you have to get one each time you register or transfer a car or Mbike.If you buy a used car over there the first thing that you should do is re tune the carby because they are all leaned out to the max to pass emissions.
Title: Re: 2T vs 4T
Post by: lukeb1961 on August 07, 2009, 02:44:44 pm
Not that I am old an cynical or anything like that… heaven forbid!!!
I doubt anybody on this forum would ever be classified as old or cynical  ;D