2 stroke vs 4 stroke

[5haun]

thats complete and utterly BS my friend

..in this case I recommend brousing several MX tech forums....most of the peeps there beg to differ

Listen newbie....before picking on serious members here , try to keep your google knowledge to your self

unlike YOU i did nt have to google it my knowledge is from experiance,about 14 bikes over 30 yrs dirt/road/2stroke/4stroke/single/twin and four cylinder,,,,,,,,,,, if ya opinon is that it is BS give me some FACTS ...wha lost for words,,
so what 2 strokes have YOU yourself rebuilt .... not ya peep pes
and not someone else's opinon from an MX forum

as i said b4 this is just my opinon,each to their own, just for those purchasing to research prices/quotes on full rebuilds for both 2/4strokes FROM BIKE SHOPS not fairytales opinon but FACTS

 

[themountain]

well...its your OPINION...fair enough

 

[roost666]

yer yer everyone gets the point e ALL have opinions BUT

we have all heard them now so STFU all of yous.....

by the way i like both!

Na its ok let em discuss there opinion's, if it gets to outa hand ill remove the post's.......I believe that the 2 banger are cheaper to rebuild but alot more frequent than the 4 stroke......4 strokes cost more but you can do alot more hours riding before requiring a rebuild......so they kinda go hand in hand really.

They say im supposed to replace my valve's every 20hrs or something(don't quote me on that im guessing cause i cant remember) in my manual.....ive owned my 09 for a year and a bit, and the motor hasn't been touched ive raced a full season and just had my first race for this year + countless hours trail riding with mates.....bet a 2banger wont last that long

But i do like 2 strokes don't get me wrong.

 

[sean01]

sean01-- balancing-- the two halfs of the crank HAVE to be aligned perfectly after the big end is assembled -at least checked to confirm they are true
i have rebuit both have you?

iv rebuilt both and obviously more than you have mate...
i have been rebuilding 2 strokes since i was 16 and 4 strokes since approx 18 and now im 35 so in that time i think i know the ins and outs.

also wat you have said above has nothing to do with balancing...
if the 2 sides of the crank are out then you will have fun trying assemble your cases..actually id bet youd crack one of the cases cause the center line of the crank would be out.
so i dont think youv built as many as you say..

they assemble cranks in jigs...
you go into a motorcycle workshop...do you see any form of balancing machine in there? or any lathe to see if runs true?
nah didnt think so..
and no they dont send em away to be done either..

sht iv even heard of them being done without a jig, but both ways require some tooling like dial indicator,feeler gauges, oxy, brass hammer, small press and some V blocks(like used in a lathe or mill)
a jig just speeds the process up

and ill agree with roost...id much prefer to own and maintain a 4 stroke as you roughly get 4 times the life out of a 4 stroke compared to a 2 stroke, BUT id prefer the 2 stroke rebuild cost

 

[motorman]

heres a question, what lasts longer:

a high maintenance wr250f/crf250x's valve-train,

or

a cr250's piston/bore/rings?

Ahh the classic question.

Whoever thinks a wr250f/crf250x's is high maintenence is kidding themselves. I own one. Change oil, change oil and air filter, check clearences every 20 hours or so and ride the guts off it. That's all I do and my bike has never skipped a beat. I also don't have to rebuild no where near as much as a 2 stroke. I have a YZ in the shed to compare too. It has had exactly 2 rebuilds and still haven't done mine on roughly the same riding. Saying that though I have done my valves (*insert honda valve problem taunt here*) .

They are really a lot close in mainence costs than a lot of people think.

 

[mattbombers]

wow, this thread is awsome!!!
MY OPINION is that bike should had fun on. not complained about which is better
p.s i love the smell and sound of 2 strokes

 

[roost666]

Ahh the classic question.

Whoever thinks a wr250f/crf250x's is high maintenence is kidding themselves. I own one. Change oil, change oil and air filter, check clearences every 20 hours or so and ride the guts off it. That's all I do and my bike has never skipped a beat. I also don't have to rebuild no where near as much as a 2 stroke. I have a YZ in the shed to compare too. It has had exactly 2 rebuilds and still haven't done mine on roughly the same riding. Saying that though I have done my valves (*insert honda valve problem taunt here*) .

They are really a lot close in mainence costs than a lot of people think.

They cant bag the honda valve problem anymore lol, i have proof, just look at my bikes motor hasn't been touched once, and let me tell you ive rode this thing hard for a solid 12-14 months.......in your face honda haters lol

The only maintenance i do is just the general....air filter, oil filter, change out oil's every 5 - 10hrs depending on riding condition's, grease linkages and swing arm bearings every 3 - 5 months.


Any 4 stroke will eat valve's if their air filters aren't changed on regular interval's plain and simple, you look after it, it will last

 

[motorman]

They cant bag the honda valve problem anymore lol, i have proof, just look at my bikes motor hasn't been touched once, and let me tell you ive rode this thing hard for a solid 12-14 months.......in your face honda haters lol

The only maintenance i do is just the general....air filter, oil filter, change out oil's every 5 - 10hrs depending on riding condition's, grease linkages and swing arm bearings every 3 - 5 months.


Any 4 stroke will eat valve's if their air filters aren't changed on regular interval's plain and simple, you look after it, it will last

Have you checked if they have shifted at all? As far as I'm aware the problem is still there. Dirty air filters just bring the problem on sooner.

 

[roost666]

i checked them about 4 months ago and they hadn't moved.....same deal with a bloke i race with.

Still has great compression.

lol get over here for a race man, ill give you a ride, then you can see for yourself haha

 

[sean01]

yeah both the yz/wrf's and the crf had and may still have valve problems but you cant really call it a problem unless you know youv done everything possible maintenance wise to avoid it.

most ppl i see buy a spanking new 4 stroke or 2 stroke and ride the guts out of it and when it goes bang they blame the manufacturer...they get what they deserve in my eyes..

my 05 wr450f has had the valves checked by me a couple of times now over a period of probly 100hr or more and they havent moved a thou since the first time i checked...
im unsure of the history of the engine as to if it has had valves and sht replaced in its time, but by the maintenance schedule it is well over due for a rebuild but shows no signs of needing one.

about the only thing i need to do to check it now is a leak down test...