OzVMX Forum
Clubroom => General Discussion => Topic started by: DJRacing on August 12, 2007, 09:38:08 pm
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I own both- modern and old, but I thought it would be good to start a new thread since it is starting to take over in another.
As I have said before, over here they are going to have the 250 2 strokes and 250 4 strokes run together. Better get the votes in on this one?
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That's 250 4T v 250 2T BRING IT ON. When the factories have to pump six and seven figure sums in just to beat privateer clubmen on 250 2T's The format will be deemed 'not workable' the rules will quickly revert to the 125 2T v's 250 4T.
HTH
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I think its the cost factor over here and thats why they are looking at having a 250cc class 2t and 4t. Yeah I know this is getting a bit modern but I'm sure the same things would have been asked way back when 2 strokes took over. Bet ya the 4t boys (back then) hated that.
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Well you know which way i'm leaning on this. I think it will be interesting, bring it on. If they are faster hey cool, but i think it will be fairly even and it will come down to whats going to be easier the race at that pace for 30 minutes. Either way showrooms are still going to be full of 4 strokes. The lites bike will just need a good pipe and it will be ready to race.
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I remember reading about the search for Cubes in Two strokes and the makings of the first 360cc husky engines. the 4 poke guys didnt like it at all and kept raising the bar as the much more agile smaller bore 2T bikes were killing the 4T in open class racing.
Two Stroke Tech is anything but at the extent of its developement. the calculations for port angle and designs have only been touched on . then there are the relatively new power valves and associated add on bits for power delivery.
The big Outboard motor guys have fuel injected 2T engines . Not that good for constantly variable speed bike engines but its only the beginning.
Check the jetskis out for some damn finely designed 2T engines.
Basic physics says an engine will accellerate faster if it fires faster and at half the revolutions of a 4T to reach the power stroke that says a 2T will be first out of a corner everytime
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Strange is it not ,that the big bore (and small bore) two strokes have been progressively outlawed in a lot of forms or motorcycle racing. If allowed the 4 strokes have been allowed to have larger cc capacities. Oh shite I just remembered at present I do not have a 2 stroke motorcycle!!! Cheers Tim
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I don't think the 2 strokes have been outlawed in racing - they've just been rendered uncompetitive by the rules allowing larger capacity 4 strokes to compete against them. Recently in the USA, Steve Lamson raced a 125 in the lites class (and was thrashed of course), but he did do it! ;)
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I know it isn't the only reasons for the changes but apparently the two strokes are not favoured environmentally. Saying that I hear runmours of fuel injected two strokes running at 100:1 ratios meeting emissions requirements. At this point in time I am a two stroke fan - when a factory recommends a major service after 10 hours on one of these high revving four strokes that you have just forked out 10-12K for its too much for me - and I know people will say this is over the top and the factory are erring on the safe side etc etc etc but for maintenance you really cant beat a $50 set of rings etc once per season!!!
cheers
Rossco
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And on the subject of Environmental concerns... ::)
I had a conversation recently with a person who was well known for 4 stroke tuning in the old days and he said that the environmental arguement just didn't hold water, due to the overlap in valve opening that happens in modern 4 strokes with their agreesive valve timing. He thought it could be as bad or worse than a 2 stroke having the transfers and exhaust open at the same time. :o
He indicated that there might be some big surprises if someone actually tested the modern 4 strokes for emissions... ;)
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put the two together in the one race and my opinion is it will always come down to the rider!
i've got a 2000 model cr250 and although i don't race it, i really enjoy a good practise day on a modern track.
it's near on impossible to hang out in a modern mx environment without having a conversation about valves.
this scares the crap out of joe average as his dollar is very important so most of us budget riders are on the two smokers even though we'd generally prefer a 4 banger.
it's the $ factor in my opinion thats keeping the 2stroke alive which brings me to what i'd really like to see.
remember when yamaha offered both the mx and yz?
gimme a mx250f please!
all the suspension of the yzf with a reliable mx style trailbike engine.
got my hacksaw ready, tt500 motor's in the shed, now where's that blown up engined yz450f on ebay?
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Vandy what about a YZ490 motor in the modern YZF450 chassis. Dump the watercooling, slip her in there and ya probably saved a bit of weight and now ya will have the brakes to slow that beast down and the suspension to keep it WFO.
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yes! another quality idea there DJR!
i think it's pretty obvious these new bikes 2stroke or 4 handle well and make some pretty amazing horsepower/torque but that reliablity thing in some cases sounds expensive.
i guess my idea of a trailbike orientated engine in a modern mx chassis is a little off the main theme of this thread but i do wonder if we've kind of gone full circle with some of the bikes on offer today.
there was some good ideas in the past, some that may still be usefull today.
back onto the 2'v4' thing.
on my modern 2 smoker, getting traction is the key to going fast, in my case anyway.
if i can get that back wheel to hook up, then it's easier for me to just concentrate on enjoying the ride. if traction is poor, then the 4 stroke guys just seem to idle around getting grip where i can't.
i still don't think either is at any real advantage but it does give us some more bull to shit over a coldie or 2.
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Vandy best we go into the 'Shed and Fridges thread' and open all those cool fridges and start empting them ;D. Yep I have to admit that I have a 06 YZF250 but I didnt buy it coz I wanted ta race full on MX on it, I just got it coz it was the yellow anniverary model. To be totally honest I actually like riding my older bikes, but on a trail ride the new one comes out coz she is a bit easier than riding a vintage 125 motocrosser on a trail ride.
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remember when yamaha offered both the mx and yz?
gimme a mx250f please!
all the suspension of the yzf with a reliable mx style trailbike engine.
got my hacksaw ready, tt500 motor's in the shed, now where's that blown up engined yz450f on ebay?
I've been thinking about something very similar, everytime I see a YZ-F250 with a dead engine on EBay... Just add a 300cc kitted TTR250 engine and we'd be laughing.
Surely the market is there for such a beast to be produced by the factories?
In more general terms, the capacities are wrong - remember back when you could run a 400F against a 250T? Essentially, they give the 4-strokes an equvilance factor of 0.625 (ie: if the class limit is 250T then 250/0.625 = 400cc for a four stroke) - this seemed to work well - as each type of bike was pretty evenly matched over a variety of tracks/conditions.
Then - while the four-strokes were still getting faster - it got bumped to 0.55, and they allowed the lites a 0.50 equlivance factor - madness!
The noise thing is an interesting, and unexpected by-product. Booming four-stroke engine noise travels further than the higher-pitched two-stroke noise, so just when we'd started to get the noise thing under control, we went and buggered it up for ourselves.
The new performance four-strokes scare me. We talk about putting a piston into a new style 2-stroke once per season, but I was talking to a bloke (Mick Wating, the guy who runs the Full-Bore riding park) the other day. He has a 2000 YZ250 that's been ridden a lot and still has the original piston... Yes it's rattly, but he reckons it still starts first kick and goes well.
When I can buy a four-stroke that can go close to that, in terms of power, weight, real world noise output and reliablilty, then I'm seriously interested.
Until then, my four-stroke ownership is going to be limited to old trailbikes.
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remember when yamaha offered both the mx and yz?
gimme a mx250f please!
Well yes......... they call the the WR 250F
I agree that the enviroMENTAL pressure on bikes going to four bangers has been the push for Decibels and Smoke out.
The missguided belief that developing 4 bangers would cut the Noise and oil emmisoins in half meant pressure and classes where skewed to make the MAnu facturers meet the tuff guidlines. Even 500Gp was sent down the 4 stroke track. A manufacturer wouldnt tool up and spend all that money to go away from a cheaper , sale-able and stable technology if it didnt need too , the road emmisions both noise and oil in the states were the down fall of bike, that mass market alone would have accounted for the call to find a 'freindly' engine that could be used across the board to power all things to disperse set up costs. Its probally not down to power, its down to Politically correct sustainable lobbying, otherwise your chainsaw and lawnmower would also still be 2 stroke. Ever wondered why most chinese bikes are 2 eees cheap and simple, ooops and no rules cause it aint for road or track use ?
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So once again I ask, 2T V's 4T. Who made it this way? Do the younger MXers of the world like spending a lot more money? Is it the manufacturers pushing it because of the money they make from the servicing/rebuilds/after market parts? Is it the governing bodies of our sport? Enviromentalises'? Surely to invite more people into a sport the governing bodies would want to keep the cost as small as possible, encourage more competitors? So are the riders getting the rough end of the stick or do they not know any better? Or is it that the marketing men aint allowed to advertise 2T as 'the most powerful, exciting, vibrating piece of machinery ya can have between ya legs' coz it would be seen as a sexist ploy to undermind lezbo's who cant ride motorbikes? Heaven knows what the reasoning is behind it all but at least they should make the classes equal pegging.
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For a most obvious reasonwhy the world has gone 4T look to the largest market and see what has changed. The US of A is undeniably the largest market for bikes and we also find California anti pollution laws extremely stringent on the 2T engine. I believe it states oil cannot be addesd to a fuel or somethong like that which even though no visible smoke even the finest metering of lubrication is seen as illegal as its deliberately added .. yeah the law is an ass.
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Who knows? The 2 strokes always made good power, no ones disputing that, If they can make a 2 stroke that rides like my 450 or 250 i.e torque across the board, not overly agressive etc, I think racers will look in to them but untill then not many people are going to touch them. Can you imagine a 50kg rider trying to hold on to a CR250 for 20 minutes, he's got no chance. Electronic controlled power valve like on the CR's? Yeah cool but didnt the Yamaha DT have that ages ago? so thats nothing new. You mention all these things that can be done to them.... why werent they? They were making 2 stroke race bikes for say 35 odd years, what were they waiting for? I'm sure engineers would have known a while ago if you did this and this to the ports you would get that. All these things that could have been done to improve them and make them more efficient, less pollutive etc, i'm sure they figured this out alot longer then a few years ago, there was a reason why they went the other way, people will pay the money, I could probably save alot racing a 2 stroke but i'm not going to do anyting that dumb, the way my bike goes i'm quiete happy chucking valves and oil filters at it and so are alot of people.It's like mud you whinge about it for a bit but you just get on with it.
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I think the manufacturers initally supported the change to 4 strokes because:
a) No-one had them, so everyone had to get a new bike. ::)
b) The higher maintenance requirements would mean more revenue through spares replacements (remember that the factories don't make much money on the intial sale anyway). ;)
However, I think that it backfired on them because they didn't realise that the increase in running costs would be so dramatic - sure they have made money hand over fist for awhile now, but now there's a lot of pissed off and broke customers out there who have possibly given riding away due to the cost. (as witnessed by the sudden and considerable reduction in sales in the USA this year).
I also think the aftermarket companies, especially those that peddle the extra loud powerpipes for these beasts will reap the whirlwind shortly as well. Noise will undoubtedly cause more and more land closures.
At least some manufacturers are getting the message - Kawasaki is a case in point. The new KLX450 not only has steel valves for longevity, but apparently the bike is whisper quiet while still being damn fast. If that is the future for 4 strokes, then it will be a good one indeed! ;) (so long as the thong nongs don't replace with pipe with something louder of course... :'( )
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I think the drop in sales may be due to all the bikes not being majoryly updated, by that i mean most of the fleet in the 07 range are pretty much the same as the 06 range with some improvements here and there. It will be the same again for the 08's except for suzuki with the efi. Maybe some people couldnt justify the upgrade? It could be a factor. I think the industry has realised there is a sound problem all the factory jap race bikes are at 96db, and most aftermarket pipes are starting to comply with it offering 96 and 98 db pipes. It has to change or we are going to loose alot of tracks :-[ We'll see how well the steel valves go, as Steve from Cisco's explained it to me a while ago, on the titanium valves they start to go when the coating on them goes, you can get around this, yes you can use the stainless valves which are stronger but they pound the valve seat more and wear that.
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Hi Ajay,
Yeah Kawasaki has done the responsible thing - created a quite 4 stroke that actually runs well without modification, straight from the showroom floor.
I can guarantee you one thing though - as soon as the magazines get hold of the KLX, the first thing they will do is replace the pipe with one that is louder.
How they can preach the benefits of a pipe that costs [in Aust] up to 10% of the original cost of the bike, reduces the weight by 0.5% [if you are lucky, and remember that the KLX is a bit of a porker], makes maybe 2% more power - BUT doubles or quadruples the NOISE LEVEL [remember decibels are logarithmic] when new [I can't imagine how much noiser they are when they need of repacking].
Boy that sounds like value for money!!!!!!!
If I was in the market for a new MXer I would buy a 2-stroke just to be different [while I still can].
VMX42
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Yeah, my bottom line was (when I was still riding): Ride a 2 stroke until they aren't available anymore.... 8)
Although if I was able to ride the KLX450 would be tempting ;D ;D ;D
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Anthony, why couldnt I imagine a 50kg rider on a CR250? I would think a 50kg rider on a CRF450 would be more of a problem. A 2T can be made to have more torque by adding weight to the flywheel. Correct me if I'm wrong(it has been know to happen) but isnt racing, be it boats,cars,trucks and motorbikes,(esspecially motoX) all about who can keep it wide open the longest, which is generally past the point of torque? The funny thing about a 2T is that once in the powerband, the power delivery is generally smooth, its only when you drop out off the power when it becomes agressive. Now, I think 4T are great bikes(as I say I have one) but cc for cc is what racing should be about. About the pollution thing, who gives a rats ass when its about racing? Does Corperate/Government people when one of them jumps into a limo, drives to the airport and hirers a plane for themselves to fly around the countryside.
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Only thing I ever liked about trail riding a 4T was not having to refuel to get home. yes they were quiet unlike the new breed of 4T bikes and that is of a concern . Many tracks are being closed because they are too close to urban development and the shrill pipes on a new 4T is not going to endear them to anyone. Can you imagine anyone allowing racing with no silencers on a 2T ?
Frankly couldnt give a damn what the current manufacturers choose to use as a power plant as im firmly rooted in old 2T bikes. Bikes with character that you need to be able to learn to ride , that didnt do it all for you. Learn where your power comes on at and pick the line and the right gear and grab the correct amount of right hand, slip the clutch and slide the rear.... May aswell buy an automatic Hyundai or catch a bus if you want it all done for you.
Will be good to see the results of the afore mentioned race. If its a tight track my beer money will be on the 2T slapping the 4T something chronic.. lighter and faster off the mark.
RD 400
TZ 750
H1 750
Now those bikes were adrenaline machines and thats fun and after all isnt fun what bikes are all about no matter how many strokes they be?
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Anthony, sadly you seem not to understand what is being said, DT's have an electricaly controlled powervalve by a servo,electrionic control intercepts the standard control and then youcontrol the opening and closing of the valve.Standard open/close powervalve curves are shit and have an on/off operation giving an (surprise surprise)on/off style of power delivery.When electronics are involved the result is more bottom end and top end over rev.An overall smoother power that can be altered to the conditions.Bit the same as variable cam timing.....any 4 bangers got that these days? Exactly the same with an ignition.Fact is they are being done right now and all it takes is a 1kg 12v battery and anyone can have one ;)
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Yep fair comment Pokey,,, But put the piston port reed valved RD400 or even an LC350 up against an electric servo assisted power valve RZ350, no contest. RZ miles better to ride in all respects in my opinion and still had 2stroke character. Why servos where not put on all two stroke power valves I don't understand. As Lozza states only a small battery to power the electronics, Hey who objects to electric starters with there batteries on modern MX and trailies...........Tim
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Too True Tim. The RZ is a way more refined bike than those nasty but fun dinasaurs, even handled reasonable comparitively.
Piston port
Rotary valves
Reed valves
Power valves
Most of that tech is circa 1900 and just look at the advances and variables that have been made and still being made using the basic principles of port angle and placement. There is yet to be found a fomula that is considered the ultimate for a 2T engine as well all need to dial on the speed and torque at different times for different tracks conditions and riding styles. same with a 4T, they also need to be tuned to bring the power on depending on the task at hand to get the best from that engine. Engines frames suspension tyres its all black magic and constant tinkering.
God help us if we are reduced to smooth power titanium monocoque "electric" MX bikes. Not sure I'd ever part with dollars for a Hoover or Electrolux 250 watt Plug N Go or a turbo charged Biofuel diesel MXer no matter how many flash stickers it had or how the exhaust smell reminded you of fish N chips.. Still be like riding in a postie bike race. Kind of takes all the challenge and fun out of it.
With technology comes refinement and engine advancement depends where the big boys.. and the lobby groups wish to go as to where the research dollars will go, thus determinining the future if any of off or on road bike racing. Dont dismiss the 2T just yet guys. a lot of life yet to be unveiled with that style of engine.
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True pokey,the yoof will find out that the next 'must have' item for the efi'd dirt bike is the 'Power Commander' they will of course be about a grand lighter(after the dyno time) but there is about 3kw all through the range. Still reckon that's better than stickers.........Ah who remembers the rolls of 'contact' and tracing adverts from magazines ;D
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yes for some reason though it would always have to many "C"'s, i think i keep cutting into the "O"s
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For a most obvious reasonwhy the world has gone 4T look to the largest market and see what has changed. The US of A is undeniably the largest market for bikes and we also find California anti pollution laws extremely stringent on the 2T engine. I believe it states oil cannot be addesd to a fuel or somethong like that which even though no visible smoke even the finest metering of lubrication is seen as illegal as its deliberately added .. yeah the law is an ass.
That was the law. It's what killed the RX-7 in the USA (they run a very limited amount of engine oil into the combusion chamber in a system very similar to a 2-stroke auto-lube set-up).
Stupid thing was, they burned less oil than a heap of conventional four-stroke engines (*cough*Chev Gen3*cough*), but the laws simply said that you can't deliberately add oil into the combustion chamber. ::)
However, I'm guessing that the law must have changed, because the RX-8 is sold in all USA states, despite having a similar oil injection set-up to the RX-7.
I agree with VMX42's post in the other thread - the rules should set the levels and leave the 'how' up to the manufacturers.
Anyhow, I'm half-heartedly trying to work out whether you can fit a DT230 engine into a newish YZ125 chassis, with programable electronics (inc EFI, eventually). I reckon you'd easily get with most/all of the conveniences, power and tractability of the newer 450 4-strokes, in a bike that would be far less maintenance intensive, more reliable and lighter.
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I asked Smurph(the injected RZ man) if this MS conversion would work on a dirt bike and be alright for the changing dymamics in a 2T engine."Will work perfectly" was his reply, but I'll send you a link to a fellow who has 2000km on his injected 350......hmmm some heartache and trials and tribulations but is 'doable' .Start looking for 03 R6 TB's NOW before everyone wants them.They run a 39mm TB and they will pull from just off idle in top gear brilliant stuff.The MS forum has been really helpful to the 'converted' to..........
I much prefer the carb with the PV and ignition control ATM. ;D
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Its nearly 3 years old this topic ;D , but a good read.
I wonder if opinions have changed. 8)
cheers
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Sure will Lozza........as soon as I find out what a TB is. ???
And while I'm in an inquisative mood...when did the world start this annoying habit of calling two strokes 2T and four strokes 4T? Is it some new form of Gen X hip text talk or did I miss the memo informing me of the change?
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Hey Firko, wasn't it Shell a few years back that had 2T and 4T oil?
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Firko,
I'd suggest TB stands for 'throttle body'
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I'd suggest TB stands for 'throttle body'
Ah! It makes sense now. I just wish people would try to avoid using text style abreviations so that old school dummies like me can understand. I've lately been spending a lot of email time communicating with one of the leading guys in refactoring the Bosch electronic fuel injection on V12 Jags and he hasn't used the term TB...he calls 'em throttle bodies, presumably so morons like me can understand.
Hey Firko, wasn't it Shell a few years back that had 2T and 4T oil?
Yeah but it still doesn't make any sense to me. Even though I find it annoying I sometimes find myself using 2T/4T, displaying how easily these things slip into common usage without us giving it much thought as to why.
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I must be getting old as well as I often have trouble with these abbreviations.
TIG welders have 2T & 4T switch options too. It refers to how many clicks at the hand piece you like to use.
Think it all has some European meaning.
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Once you fatter and slower 4 strokes work well
;D
(http://i245.photobucket.com/albums/gg71/marcFX_photo/SANY0101.jpg)
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Yeah but it still doesn't make any sense to me. Even though I find it annoying I sometimes find myself using 2T/4T, displaying how easily these things slip into common usage without us giving it much thought as to why.
The term T for stroke is derived from most Euro languages (tempi=Spanish & Italian temps=French and takt German & Dutch) that the word for time/clock refering to an engine begines with the letter T.
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Hey Firko that would make the Jag a 12T "Its all about style"
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.......and if a V1 was an explosive device would that make the V12 12X more destructive when it explodes too? :-\
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The term T for stroke is derived from most Euro languages (tempi=Spanish & Italian temps=French and takt German & Dutch) that the word for time/clock refering to an engine begines with the letter T.
So why use it in English for f**k sake? Methinks it's new age metrosexual bunkum. From here on in, kick me in my ample arse if you catch me using 2t terminology in anything I write. Somebody has to save the English speaking world from this pompous new age shit. ;).
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Why have you used the the German word 'verboden' in sentences?
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http://Why have you used the the German word 'verboden' in sentences
Who, me? Not me I'm glad to say Loz. If I have I'd like you to point it out please. ???
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Why have you used the the German word 'verboden' in sentences?
Why the angst? Is it verboten to use German? should we also drop kindergarten, muesli, abseiling, doppelgänger. kitsch, hinterland, iceberg, kernel, lager, etc.? English in the 5th century was Germanic, ffs. the Angles (Baltic), Jutes (Jutland), Saxons.. ie all northern Germans who threw on a rucksack, lobbed in after the Romans and started to build Biergartens!. ;D
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Foreign language words get used when there's no English equivilant, or they do a better job than the English version (and let's face it, despite the nice leather and timber trim, English words are prone to black-outs, oil leaks and electrical fires).
They also get used to increase the wank factor.
Whether using a foreign word is better or a wank, is up to the speaker/writer.
The alternative is a 1984-esque scenario where there is only one allowable word for any particular thing.
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I agree Nathan-each to his own but what bothers me is why the 2T/4T evolved at all.
I have a theory though. I'd be pretty surprised if most of us really thought that Sushi tasted good. But because media and style fashionistas* tell us it's so wonderful, we believe that it must really be worth eating and not wanting to be seen as uncool, eat the shit even though we secretly detest it. The 2T/4T thing probably evolved the same way. Some new age tuning wizard probably started using the term in some obscure article on polymer gasket infusion in 'Cam Profile Monthly' and not wanting to be seen to be out of touch with the latest in techno jargon we conciously start using the term in a bid to be seen as 'cutting edge'. Before long the term has achieved general usage with Gen X techno whores.
*Note my cool use of the Italian noun just to show that I can be just as cool/stupid/guilty.
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I agree Nathan-each to his own but what bothers me is why the 2T/4T evolved at all.
I have a theory though. I'd be pretty surprised if most of us really thought that Sushi tasted good. But because media and style fashionistas* tell us it's so wonderful, we believe that it must really be worth eating and go ahead and eat the shit even though we secretly hate it and don't want to be seen to be uncool. The 2T/4T thing probably evolved the same way. Some new age tuning wizard probably started using the term in some obscure article on polymer gasket infusion in 'Cam Profile Monthly' and not wanting to be seen to be out of touch with the latest in techno jargon we conciously start using the term in a bid to be seen ass 'cutting edge'. Before long the term has become general usage.
*Note my cool use of the Italian noun just to show that I can be just as cool/stupid/guilty.
Hey Mark, I can't imagine too many references to 2T in " Cam Profile Monthly"
Stan
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I have a theory though. I'd be pretty surprised if most of us really thought that Sushi tasted good. But because media and style fashionistas* tell us it's so wonderful, we believe that it must really be worth eating and not wanting to be seen as uncool, eat the shit even though we secretly detest it.
I like good Sushi. Bad Sushi is evil. There is an awful lot of bad Sushi around these days.
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I like good Sushi. Bad Sushi is evil. There is an awful lot of bad Sushi around these days.
I can't believe what foreigners pay for Sushi, I was in Zurich and they were getting 4CHF for bad Sushi rolled by a Korean.
The 4stroke 2 stroke debate is a feature of every bike magazine these days. Doesn't help that the Yamaha brand series for up and coming stars in the US was won by a YZ125 which wiped the floor with the 250s.
I think the open 4 strokes rock (try the 2010 RMZ450) just smooth horror big power, but my RM500 doesn't feel any less powerful, just the 450 has drive any time you pull the trigger. I want to get them both out together some time and plonk a good rider on both, be interesting as hell.
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2009 RMZ450 5-speed disks, Fuel Injected, 46.5HP @7500 torque 30.8 @7000 113kg (full) 12.2" rear travel, seat height 37.5"
1983 RM500D 4-speed drums, reed-valve, 46.0HP @7500 torque 34.4 @6000 113kg (full) 13.1" rear travel, seat height 37.2"
RM500D - Dirt Rider October 1983
http://cid-407d7ef0965d3991.skydrive.live.com/browse.aspx/Racing%20Model/Magazines
RMZ450
http://www.motorcycle-usa.com/240/1724/Motorcycle-Article/2009-Suzuki-RM-Z450-Comparison.aspx
now that all has to be taken as a heck of a bike, but I am left wondering what an RM500cc two-stroke
would be developing if they had continued to work on them over the past 26 years.
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Quite a few years ago our club had Phil Irving as a guest speaker at a dinner and when he was taking questions I asked him would 4 strokes take over from 2 strokes and he replied only if we let them as his belief was that we have not scratched the surface of 2 stroke technology but enviromental laws may stop them reaching their potential.
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ozone layer/emissions trading hasn't got us quiet yet.. 8)
YZ and 04/06 model RM 2T are still available to purchase and order.
cheers
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I have cut and pasted the post below from cr500riders.com
I got a copy of Transworld MX at the store today. They rode Service Honda's KX500AF. Short article, not as good as the write ups MXA does...but you get the idea. It's to the point.
Bottom line is the test rider who had only ridden a 500cc two stroke ONCE before was still faster on the 500 than his 450
Here are his times;
Rider: Brendan Lutes
lap 450F 500AF
1 2:24.33 2:21.65
2 2:23.24 2:22.71
3 2:24.79 2:20.99
4 2:23.99 2:20.36
Time and time again lap times PROVE 500AFs are often faster around a track than 450s. They aren't your girlfriend's bike. You need to; 1 Learn how to ride. And; 2 Stop curling beer cans and start pumping dumb bells if you want to be "competitive" on a 500cc two stroke. The weight advantage is there, the subsequent handling advantages are there, the power advantage is there and the power delivery isn't a problem if you obey rules 1 and 2.
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2009 RMZ450 5-speed disks, Fuel Injected, 46.5HP @7500 torque 30.8 @7000 113kg (full) 12.2" rear travel, seat height 37.5"
1983 RM500D 4-speed drums, reed-valve, 46.0HP @7500 torque 34.4 @6000 113kg (full) 13.1" rear travel, seat height 37.2"
Cool interesting to see the stats on top of each other like that. I might frame those and hang them on the wall. I like that the RM500 makes more torque at lower RPM.
Well moves are afoot at the moment to get rid of the 450s, the AMA are considering to reduce the open class to 350cc. KTM must have good inside information as they already have built a 350 as they did a 2strokes 150cc. As usual the factories are looking for a way of slowing down guys who don't have their budget.
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Marc,
No need to slow down the 450s by decreasing their capacity. It will only add to the cost of racing [and the short term profits for the factories]. Simply make the existing bikes comply to sensible noise regulations and you will achieve the same thing [and benefit the entire sport].
VMX42
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Marc,
No need to slow down the 450s by decreasing their capacity. It will only add to the cost of racing [and the short term profits for the factories]. Simply make the existing bikes comply to sensible noise regulations and you will achieve the same thing [and benefit the entire sport].
VMX42
Never a truer word spoken :)
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The thing with these modern 4 stroke shitboxes is that (as with the rest of modern society ) they are dumbing things down >:(
The standard of riding over the last 10 years from Pro to club rider has deterioated a lot. By the time the current generation of young juniors turn senior i believe it will be twice as bad >:(
Thankfully the World Junior champs have dropped the 250F class for this year and competitors will have to ride 125s :)
Most kids these days get off an 85cc bike onto a 250F and within 6 months all those skills they learnt on there 2 strokes are gone and they become couch spuds on noisey lawnmowers ::)
Thank christ those ridiculous 150 4 strokes never took off ::)
The current generation of superstars Reed ,Stewart,Villipoto,Townley, cairolli , Machio all learnt there skills on 2 strokes and i believe unless we ditch the 4 stroke rubbish this generation will be the last of the real racers :(
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"2T OR 4T" What a load. I am an Australian! and when it comes to stroking,
Yep certainly when it comes to stroking you Aussies are in a class of your own ;D
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"2T OR 4T" What a load. I am an Australian! and when it comes to stroking,
Yep certainly when it comes to stroking you Aussies are in a class of your own ;D
It's only because we don't have easy access to sheep!!!
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It's only because we don't have easy access to sheep!!!
[/quote]
judging by how tight Aussie Rules players wear their shorts sheep are not your main interest ;D
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The shorts have to be tight - obviously you don't know what its like to trip on your own tackle ;D
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"2T OR 4T" What a load. I am an Australian! and when it comes to stroking, it will be as it has always been! horses for courses.
Yep certainly when it comes to stroking you Aussies are in a class of your own ;D
Gees, what was I thinking? I should have seen that coming.
Nice to see the team still defending the front line though :D Thanks.
I think I might have been celebrating "not having a drink for five weeks" ::) either that or I was distracted by the exchange rate again.
Also looks like I may have been in a patriotic “where’s my darling mood”, singing the national anthem as I returned home. I reckon My drink got spiked ;D ;D
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(http://i155.photobucket.com/albums/s297/Lozza85_2007/IMG-1.jpg)
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Just caught up with my friend who bought the KTM450SX as mid life trail bike, he is not enjoying the experience, quite different from an XR600. ::) If you came off 2 strokes easy to adapt to modern 4 stroke, but if you came off older 4 stroke it is probably a shock.
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Just caught up with my friend who bought the KTM450SX as mid life trail bike, he is not enjoying the experience, quite different from an XR600. ::) If you came off 2 strokes easy to adapt to modern 4 stroke, but if you came off older 4 stroke it is probably a shock.
I described my WR250F as a two stroke four stroke and as a four stroke two stroke 8) - meaning it had the characteristics of both depending on how you rode it ;); and I loved it 8).
If your friend is not enjoying his KTM450 I can only imagine he is trying to lug it along using the very bottom end power. It can be done but tell your friend to twitch his bum, move forward and 'give it the berries' ;D.
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... KTM450SX as ... trail bike ....
That's most of his problem right there.
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Son knows his bike well and could tell something just wasn't right.
crf250 one stretched valve= new bits, piston and rings all for $650 :P beat the $3500 bill :P
cheers
5-6 + hours shed time
Part two:The two stroke YZ250-$164.80 for ebay piston and rings,3 hours total shed time...all done ;D :P
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Just got off the phone to my mate with an 2010 KTM530,which he loves and has owned other 530,525 KTMs before this one and he just told me on his last ride smoke started billowing out big time out of the exhaust.
This bike has only done 20 hrs,3rd or 4th ride from memory and took it back to his dealer.
Apparently a ring tension problem on the 2010 models and covered under warranty.They replaced the piston as well.
All is good again.....for now ;D
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I remember reading about the search for Cubes in Two strokes and the makings of the first 360cc husky engines. the 4 poke guys didnt like it at all and kept raising the bar as the much more agile smaller bore 2T bikes were killing the 4T in open class racing.
Two Stroke Tech is anything but at the extent of its developement. the calculations for port angle and designs have only been touched on . then there are the relatively new power valves and associated add on bits for power delivery.
The big Outboard motor guys have fuel injected 2T engines . Not that good for constantly variable speed bike engines but its only the beginning.
Check the jetskis out for some damn finely designed 2T engines.
Basic physics says an engine will accellerate faster if it fires faster and at half the revolutions of a 4T to reach the power stroke that says a 2T will be first out of a corner everytime
Bump..the cost of the two stroke is by far better than 4 stroke.WE LOVE IT. ;D Boy child(16yrs)is also stoked with the YZ.Don't mean to brag ,but he was running second on Sunday in the all in seniors class with the 4 stroke(21yrs) in first place.He was told to have more faith in his tread on the gravel track.He really has progressed with the 2 stroke in his racing-he say's its more fun 8)
your in projecttwo50 oz ;D
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Learn to ride on a 125 2/st.
Then swap to a 4/st and go fast. :)
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Learn to ride on a 125 2/st.
Then swap to a 4/st and go fast. :)
True very true.
Based on first year apprenticeship wages the 2/st the way to go,at this point in time.
Mum and Dad ain't paying no more for dat 4/st ;) ;D cheers Mum
http://ozvmx.com/community/index.php?topic=11702.0
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Learn to ride on a 125 2/st.
Then swap to a 4/st and go fast. :)
In my case it was learn to ride on 2 strokes,buy a 4stroke 20 years later,learn that 4stokes are top heavy pigs that made me a worse rider and poorer for it,1 year later build a light 2stroke and realise that
i enjoy riding again ie fun and makes me look good....these are my opinions only but will NEVER go back to a 4 stroke again.
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Husaberg are going to release a couple of two stroke models next year.
http://www.husaberg.com/EVOLUTION-REVOLUTION.23.14.html?nodeID=1074&cHash=754978a5fa
They are just rebadged KTMs apparently!
Apologies if this has been posted somewhere already.
Tex
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You have a point Monaro but I was thinking of those new revvy, no power down low ones. :)
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....
They are just rebadged KTMs apparently!
Apologies if this has been posted somewhere already.
It had been mentioned before, but that's the frst time I'd seen anything other than rumours/speculation.
Weird that they're just rebadged KTMs - I'd been assuming that KTM would use Husaberg as 'production product evaluation' branch, so they could try weird/whacky stuff without risking the KTM brand image.
TE nomeclature might make sense in Husaberg world, but its gonna be annyoing for the rest of us...