[woodyrm250]

Ok now I've never a form on the diffrences, the pros, and the cons on 2 and 4 strokes. so i thought i would make one.

And I also wanted to know what the crap the big fuss is about how 4 strokes suck :roll:. I cant say anything cause ive never ridden a 4 stroke ive oly ridden my rm250 :mrgreen: so i thought you guys could tell me what the pros, the cons, and diffrences between a 2 strokes and 4 strokes :madd: .

 

[roadterrorist_2]

2 stroke vs 4stroke

i think the main differance is the amount of usable power as in they dont have a powerband that gives you a boot in the pants after 2500 odd rpm, they have a mucher smoother power build up, but as you know, a 250 two will always whip a 250-400 four,

 

[roadterrorist_2]

i think that two strokes fire every revolution four strokes dont,an because they have twice as many power strokes per revolution, they have to be raced against bikes twice the engine capacity, thoagh with the developments being made with four strokes the deficit is slowly being reduced

 

[woodyrm250]

ok kool but how about racing, trail, and dune riding wise. like Whats the better bike for racing, trailriding, and dune riding. Cause thos are the tree things i do. racing i'm about to start and trail and dune riding i do all the time. today i rode a xr250r honda and it was really diffrent. it pulled hard all the way through. but my rm250 just starts accelerating the bam the powerband hits and just takes off like a bat out of hell. :lol:

 

[roadterrorist_2]

welllll, you prob already no but ill tell u what i considered, two strokes have a lot higher maintenance requirements than four strokes, but parts and the actual bike are a lot cheaper to buy, rm 125 is $8000 here but rm-z 250 is around $9000, do you race against four strokes, if you do id probably go for the four stroke 450 definately not as light and nimble as a 250 2 stroke but like you said, they pull from anywhere in the rev range , my experiance in sand the 250 four was ideal, but i dont ride in sand to often anymore, anyway, good luck with your riding, hope i helped i little

 

[Dave2122]

It all started in the late 90's when Yamaha came out with the YZ 426. Once the AMA allowed it in the 250 class and the Govornments went with cleaner air regulations the die was cast. Since that time we have been force fed the 4 stroke s. Which contrary to popular belief are not so cheap to race. If you have ever priced out a top end rebuild on a current 4 stroke MXer you would have a coronary! The day is coming when the big 4 wont even offer a 2 stroke MXer Even my 2 street bikes are RGV 250 2 strokes :lol:

Keep smokin!

No Diesels.

 

[roadterrorist_2]

you gotta admit the YZf's are worthy bikes, I'm sorta gettin used to the fact that 4 strokes just about always holeshot, but come the tight sections and they start gettin into strife,those extra 10 or 15 kilos make a helluva differance.


<ps> whats this i hear about not being able to buy 2 stroke MX'ers soon, down here in aus they're on a comeback, the KTM's are winning everting now

 

[Uncle Bob]

Well if you care anything about the environnement a four stroke is much cleaner running.

 

[Dave2122]

I think that the environment could do a lot better if we stopped much bigger offenders than a small 2 cycle engine. We send giant booster rockets through the ozone and have massive wildfires pumping plumes of smoke into the atmosphere....So lets helo the environment by running 2 stroke dirt bikes..........Thats the best joke I have heard in years :lol:

 

[themeatmanlandry]

I think that the environment could do a lot better if we stopped much bigger offenders than a small 2 cycle engine. We send giant booster rockets through the ozone and have massive wildfires pumping plumes of smoke into the atmosphere....So lets helo the environment by running 2 stroke dirt bikes..........Thats the best joke I have heard in years :lol:

How many rockets are launched each year? I believe that rockets only emnit water and carbon dioxide. Solid fuel reaction.

Forest fires, although preventable (now THERE'S a topic), are a necessity on our planet. Engines that use reed valves, allowing unburned fuel to blow easily through the engine can be easily eliminated.

 

[Uncle Bob]

No joke !

First of all wildfires are just that wildfires, natural products being burned. Sure I wouldn't want a lung full of that smoke in me but relatively harmless to the enviroonement in the long term. They've been around since the dawn of time.

Don't underestimate the pollution of a two stroke, up to 40% of the oil and gas you put in it is blown unburned out of your exhaust pipe. The pollution levels of a two stroke over a four stroke is on the order of 100 to 1. That means that you would need to run a four stroke 100hrs to equal the pollution of a two stroke running for 1 hour.

More pollution is caused by people mowing their lawns with two stroke mowers one hour a week than they do commuting to work 2hrs a day 5 days a week in a car.

Don't care about the environnemet ? That's your problem but a lot of people do and two strokes are being restricted in more and more places. So if you want to be able to ride in many different locations a four stroke for that reason alone would be a better choice.

My 2 cents

 

[Dave2122]

I never said I didn't care. I just think there are a million problems causing the pollution of our enviroment. To say a 2 stroke pollutes is correct. Now to tell me that they are causing enough of a percentage of the damage to the environment to stop making them to me is pure nonsence. I don't want to argue about it, it is a free society we both live in and we are allowed to have our opinions. My opinion is..............

:lol: 2 strokes....Smoke'em if you got'em :!: :lol:

 

[Dave2122]

Incidently the United States under President Clinton decided we should'nt log old growth forest and thet no fire roads should be made to have access to these remote areas. Once that was done, all it took was a lightning strike to cuase the massive wildfires we had in the late 1990's. So if people knew that wildfires can be prevented through forest managment then you could see that wildfires can be prevented to a large degree. The ones that do ignite can be contained and controlled easier. Also if you knew anything about the burning of living trees and wood in general you would know that there are Greenhouse Gases released during the burning process that are infact very harmful to the Ozone Layer. That is why any woodstove built after 1991 has to have a catalytic converter.

 

[themeatmanlandry]

Actually, the 'greenhouse' gases do not harm the ozone layer. CFC's, or Freon, harms the ozone layer. Greenhouse gases buildup and add extra insulation to the atmosphere (so they say . . . I ain't noticed nuthin'). The unburned VOC's from your trusty bumblebee combine with atmospheric nitrogen to form lower-level ozone, which causes lung irritation in some people.

Pollution is pollution. And yes, you are right about the forest fire management thing.

 

[Uncle Bob]

I just added to the list of pros and cons you asked for, comparing two and four stroke engines. I explained that a four stroke is more environnementaly friendly.

You responded by attacking NASA and Smokie the bear for the worlds pollution problems.

Fact is that two strokes are extreme polluters for their size. However I've heard that someone has come up with a solution that could reduce two stroke emissions by up to 90%.

Now back to our regularly scheduled program.

 

[svhooligan]

2 stroke motors production might cease outright in the US but theres far too many of them throughout the world and thes countries have more problems than dealing with the environment.

I agree that 2 strokes are big polluters. they're the #1 polluter of the air AND water(all that oil in the exhaust..) Problem is theres just no changing the ENTIRE worlds opinion on using these handy little motors..