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Yamaha does well because it's the only KTM alternative with good dealer support, and has good suspension. If you think the KTM motor isn't usable I sincerely hope you race quads.
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Up in Canada....they are doing it the right way. You can race a 2 stroke , but CAN NOT modify the cylinder at all. Everything between the exhaust port and intake port....has to be left stock. You can put a pipe , reeds and else on a 250 2 stroke.
That makes both bikes real similar power wise......and in some case the 4 stroke is putting out even a tad bit more.
This rule should be in place here in the states. The fastest guys will be running the 4 strokes anyways , because that's what the factories supply these teams with.
Having to run a 125cc 2 stroke up against these factory 4 strokes....is not only wrong , but a God damn crime!
It boils down to...." We want all the money we can get from the people buying our bikes and parts. "
We need to rememeber the classes were 125 and 250. Equal displacement rules don't make sense. A 125 4 strokes has absolutely zero chance. Hondas 150 thumper is only good against the 85s, it can't really keep up with the superminis. And what about all the 450 4 strokes? What do they race?
What the AMA really needs to do, is implement a rule for 2 years from now. Tell the big 5, they got 2 years to build a 200 and 350 4 stroke, or a 125 and 250 2 stroke. Upping 2 stroke displacement can work for now, but we can't keep bitching that all the competition is hurt when we don't address the fact that bikes have gotten too fast. Slow down the thumpers, don't speed up the smokers.
Well, other than the 'no mods between the intake and exhaust manifolds'- that smacks of Stockholm Syndrome, and stops cheap and easy tuning options.
The various series around the world that allow equivalency, show that 4ts will not be decimated by 2ts.
DC - The person that could change the rules - has evidence of this through his own, other series - GNCC XC2.
So, DC - why do we never hear from you on this?
I suspect that certain companies, that have a vested interest in continuing this BS Handicap Class Racing Rules, may have their knives at his throat/ balls.
This is a pathetic set of class rules, that deserve / need to be done away with, Now.
i almost think that there needs to be a cc cap based off of similar HP and torque... just not sure where that would be. a stock 250 smoker (the orange one) is around 50hp and 28-30ftlbs of torque. that may be a good baseline to start from. the 350 is in the upper 50hp range with similar torque and a powerband that is literally twice as wide as any 250 i've ridden.
I think the old KTM 250 is something like 50 to 52 hp stock. I'd assume there's a extra horse or 2 in the new 2017 motor. So atleast it's not super far behind the 350 is dyno wars.
I'd say the AMA needs to talk to some engineers to decide what the CC limits should be. They also need to go ahead and get rules in place for electric bikes. There's absolutely zero reason to delay doing so.
I'd like to see more aggressive rules in the name of sound as well. And the weight limits should be lowered, production bikes are nearing the limits every year.
It is not just about peak HP. 2Ts put out too much HP (relative to their peak) at small throttle openings. This is a function of 2 stroke expansion chamber dynamics. This hard hit at small throttle openings dramatically reduces min corner speeds relative to a 4T. A 250 2T could probably put out more Peak HP than a pro-built 250f, but except for maybe a wide open sand track...it will get killed mid corner by a pro-built 4T. Every corner...corner after corner...it add up. It would not even be close.
To say a 250 2T would "blow everyone away" is comical. Currently, 250fs are about 2s a lap slower than 450s. So...suddenly 250 2Ts are within 1 second of 450fs? Please...they were 4-5s a lap slower BEFORE EFI, and EFI has only increased the advantage of 4T over 2T because of how they can tune partial throttle behavior.
On current AMA pro tracks, a top 250 2T would be dropping 4-5s to factory 250fs. You guys are delusional.
And it would make too much sense
And Honda would be all mopey
And everyone would be happy
Except Honda
We can't have that
That's why.
Top 450 Guy colt earned $100000 after winning the title last year , second made $60000 and the third place guys got a regular job!
250f class in Canada is a hobby at best!
With no support its too expensive to race the small fourstroke , so 5 out of the top 10 were basically stock 2smokes!
Pit Row
It would be a bloodbath.
So yes 2 strokes can be a handful in sweeping, low traction turns. But you just need to be careful with your right hand, or go in a gear tall and use the clutch.
No chance at all for the 2 stroke, means nothing to bother about on the 4 stroke side.
But i guess especially privateers will go with the 2 stroke.
Thats what the industrie doesnt want!
I rebuild a blown 4 stroke engine cost roughly $3000 (KX250F 2011)
I rebuild a blown 2 stroke engine cost less than $1000 (KX250 97 & YZ125 2005)
If a 4 stoke is blown it gets ugly and costy!
In almost 25 years i have never seen a 2 stroke engine blown like most 4 strokes if they are blown.
Bought 2 2011 4 strokes last year with blown engine.
Both had the same issue, Conrod broke and went through the case.
Since i am riding i just saw it once on a 2 stroke.
You try to dispute what I am saying...but you do not even realize you are essentially making my point...
You say...
"Yeah they are more rpm sensitive"
"So yes 2 strokes can be a handful in sweeping, low traction turns"
"...But..."
The problem is, the "but" is never enough to make up for the inherent power band issues of a 2T.
In other words...in corners...they are slower. Which is what I said...
You imply that there is an overt bias and conspiracy against pingers. Sorry but there is no such thing. There is only business, and 2T MX is a sliver of a sliver of the market for the mfgs. 2T MX enthusiasts do not even register on the business plans of the mfgs. Sorry...but there is no conspiracy. We do not represent enough of a factor for anyone to bother coming up with a conspiracy against us. This is the sad truth.
The way you worded your previous statment, it sounds as if 2 strokes are literally on or off depending on rpm. And this isn't true at all, wide open at 3,000 rpm my bike pulls harder than it does at 10,000 rpm with the throttle cracked just enough to make the pipe go pop.
Don't get me wrong, I miss some of the characteristics of my old 250F. But I'm much faster on the 150, and more importantly. I don't give a crap how hard I am on the bike. Wasn't abnormal for me to short shift the thumper because I wasn't ready to buy valves, springs, timing chain, cut valve seats, more expensive piston, and put in the time for that crap. The 2 stoke, she sings all day long.
All we want are the rules to be evened up a little.
I hate to admit it but 4 strokes rule motocross you either accept it embrace it or just enjoy riding a smoker and accept it for what it is a whole heap fun but not the best tool for the job
But, I'll never argue for a 'little' change, only complete capacity equivalency being allowed. As I so often cite - the existence of DC & Co's rules for equivalency, and, from what I gather, No rules against engine mods, in GNCC XC2 racing. But Hell No, the same rules can't be in place in Pro Motocross. Fair in one series he controls, not fair in the other. So very strange, that.
There is "an overt bias and conspiracy (not the word I'd use, but I'll repeat what was written) against pingers". Simply, there is just that - by the rules that have allowed them to have twice, or 3/4s more capacity, being continued with.
It's always amazing that people don't realize this, even as they are writing / talking against it being so.
It's a ridiculous set of rules, that was only needed when engines the levels of XRs / TTs / DRs and KLXs were the type used. Mind you, CCM raced in a capacity for capacity era, and, managed to have Steve Whitlock / Honda target them for 'bothering' their 2ts :All with a technically ancient engine...... maybe that's what got Whitlock's / Honda's goat, being embarrassed by what they would consider a Dinosaur, when their own efforts with 4ts had failed (look up Rex Staten on the Honda 4t MXer) .....woohoo:
Proponents of handicap class racing rules, bleat about equivalency being unfair, revealing just how little they know about engines. Hell, there is so much more to come from 4ts - just one example being that we've yet to see even the most basic of variable valve control used on dirt bikes. I have the feeling that that will come soon, with the example set by the coming GSXR1000Rs ball and ramp (a simplistic description, but apt for the purposes of getting it into the heads of some) cam sprocket system.. A quite simple, cheap WSBK rule dodging VVT set up.
And., all through this, the ones that say it wouldn't be fair, whilst so often crowing about 4ts superiority, show how little they really believe in the type of ICE unit they so regard as being the best, really being that. They need to think about their stance, but, with their confused mindset, may not be capable of doing so..
Just as foolish a rule as exists now.
Size for size, nothing more, nothing less.
Anything else, is contrived Bull Shit, of the highest order. Well, perhaps it's better described as being of the Lowest order. It's a disgrace to our sport, that such Handicap class rules still exist.
Im still all for making the rule equal now. However, Im confident, that at the highest level, things will look the same as without the equality rule. If there had been an incentive to develop 2T's at the same rate as 4T's, then we may be singing a different song. Im just saying it may be too little too late.
At the end of the day, the cc for cc argument is for AMA moto and supercross (GP's too I would assume). Those are very very small numbers from a manufacturers standpoint. A lot of racing below AMA pro level in the US allows for equal size racing. Sure, there are some instances where you see two strokes winning, but by no means has there been change of any significance. That goes for all MX, cross country worldwide where cc for cc is allowed. Some sucess has been seen on occasion (Straya, Canada,etc) but by no means any sweeping changes in the large markets where companies look to make a profit and recoup costs. MX, cross country racing in the world sees equivilant options which is like a large scale trial, letting the market decide. If the numbers were noticably changing back to 2T's, the factories would have no option but to revisit. But it just isnt happening. Im a 2T guy, unfortunately reality sucks. The only bikes in my garage are two strokes.
The majority buys fart boxes, the minority talks about two strokes.
As it stands now (because of how long the unequal rule has been allowed) the rule is not a handicap rule, yet a rule of irrelevance.
Strangely, I feel as this topic has come up before, at least one other time?
Post a reply to: 250f class with 250 2 stroke?