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why 2 strokes dont last as long as 4???

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Hey guys, ive been wondering this question for a while now, why is it that a 4 stroke top end will last longer than a 2 stroke? is it because with a 4 stroke you get better lubrication?

Thanks for any explanations :smirk:

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Hey guys, ive been wondering this question for a while now, why is it that a 4 stroke top end will last longer than a 2 stroke? is it because with a 4 stroke you get better lubrication?

Thanks for any explanations :smirk:

Because four strokes are harder and more costly to rebuild so most normal people push them past the service range.

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Hey guys, ive been wondering this question for a while now, why is it that a 4 stroke top end will last longer than a 2 stroke? is it because with a 4 stroke you get better lubrication?

Thanks for any explanations :smirk:

you got it bass-ackwards my brotha.

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Because you ride the PISS out of a two stroke, Like 10,000 RPM's and up. MOST four stroke riders ride them at Much lower RPM's. If you bounce of the Rev Limiter then you will probably get the same amount of hours out of a 4t then a 2t.

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Because you ride the PISS out of a two stroke, Like 10,000 RPM's and up. MOST four stroke riders ride them at Much lower RPM's. If you bounce of the Rev Limiter then you will probably get the same amount of hours out of a 4t then a 2t.

Actually the 4 strokes run at about the same or higher RPM's. Don't confuse tone with RPM's.

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Not true in every case my brotha

no, not in every case, but in many it is.

new tech. 4t's are more of the high strung race machines than 2t's. they require closer maint. intervals to maintain the tolerances and aren't as forgiving when operated beyond the recommended tolerances.

i think that frequently 2t riders will do topends more frequently because of the simplicity of the rebuilds. it hardly means that they have to be done when they are but for a couple hour and $120 investment it's easy to justify. truth be told, a lot of trail riders can easily push their 2t bikes well over 200 hours on a topend. most consider doing that many hours on a 4t topend to playing with hand grenades. hardly a good idea. anyways, these are just my anecdotal musings. your results may vary.:smirk:

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Smokers have ports in the cylinder walls. The old air-cooled type 4 stroke (e.g., Honda XRs) would last longer than smokers because they have big, heavy, long-skirted piston slugs that rode at low rpm in bores with no ports. Today's high performance 4 stroke engines are prone to much more wear, as they have tiny little "slipper" pistons that will "rock" in the bores, and everything runs at very high rpms. So it used to be that 4 strokes would last longer before a rebuild, but that is no longer the case. Today's 4 strokes are also likely to require more than a piston kit at top-end time.

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no, not in every case, but in many it is.

new tech. 4t's are more of the high strung race machines than 2t's. they require closer maint. intervals to maintain the tolerances and aren't as forgiving when operated beyond the recommended tolerances.

i think that frequently 2t riders will do topends more frequently because of the simplicity of the rebuilds. it hardly means that they have to be done when they are but for a couple hour and $120 investment it's easy to justify. truth be told, a lot of trail riders can easily push their 2t bikes well over 200 hours on a topend. most consider doing that many hours on a 4t topend to playing with hand grenades. hardly a good idea. anyways, these are just my anecdotal musings. your results may vary.:smirk:

me thinks the same!!!

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this exact post was bought up not long ago

Yeah I was thinking it looked familiar. Could be another trolling thread but maybe a naive legit question.

I don't know what 4t powered bike the op is riding and if he is using the powerplant as it was intended for as in "WFO" but I personally can get many more hours out of a 2t topend over the modern high-revving 4strokes.

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Because you ride the PISS out of a two stroke, Like 10,000 RPM's and up. MOST four stroke riders ride them at Much lower RPM's. If you bounce of the Rev Limiter then you will probably get the same amount of hours out of a 4t then a 2t.

this is not true at all

two strokes may sound like they are reving high, but only the little 125 and lower ones can do it, the bigger ones dont make any power that high

the 4 strokes run much higher rpm, 25-35 % higher rpm is where the power is, you may not realize this if you have never rode both, at least look at dyno's

I get the same hours out of both, both wear out the pistons over time, the short skirts on the 4 strokes still scare me

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if I could only make my 250 2t see 10k with out dropping a gear on a downhill asphalt coast.

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this is not true at all

two strokes may sound like they are reving high, but only the little 125 and lower ones can do it, the bigger ones dont make any power that high

the 4 strokes run much higher rpm, 25-35 % higher rpm is where the power is, you may not realize this if you have never rode both, at least look at dyno's

I get the same hours out of both, both wear out the pistons over time, the short skirts on the 4 strokes still scare me

Ive owned both man. And In my case it was true. I got around 100 hours on my Yz250 each time and I'm currently riding a 426 with over 200? and its still golden. I had a Trailtech with an digital tach on both bikes... and guess what. Im running 25/30% lower with the 426 doing the SAME riding...

Thank you That is all.

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Ive owned both man. And In my case it was true. I got around 100 hours on my Yz250 each time and I'm currently riding a 426 with over 200? and its still golden. I had a Trailtech with an digital tach on both bikes... and guess what. Im running 25/30% lower with the 426 doing the SAME riding...

Thank you That is all.

The 2 strokes are falling off around 10,500 while the 4 strokes are continuing up to and over 11,000. A 4 stroke's peak HP is often made at a higher RPM than a 2 strokes. I imagine that is why 4 strokes have a rev limiter, so you can't ride the "PISS" out of it like you can with a 2 stroke.

141_0312_250_32_z.jpg

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I had a Trailtech with an digital tach on both bikes... and guess what. Im running 25/30% lower with the 426 doing the SAME riding...

Thank you That is all.

That's because the 426 makes quite a bit more torque down around 4-6krpm than the yz250. He's still right though as even your bike makes peak power about 500-1000rpm higher than the yz250 did. Plus, your bike is a 9 years old and isn't exactly a modern 4t racing machine.

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The 2 strokes are falling off around 10,500 while the 4 strokes are continuing up to and over 11,000. A 4 stroke's peak HP is often made at a higher RPM than a 2 strokes. I imagine that is why 4 strokes have a rev limiter, so you can't ride the "PISS" out of it like you can with a 2 stroke.

141_0312_250_32_z.jpg

they fall off at 9, just look at the dyno, and they fall off so hard it's pointless to keep reving, people shift as soon as the power starts to fall off, on two strokes when you hit the peak they drop off like your hitting a wall

most modern 4 strokes will pull hard right to the rev limiter

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they fall off at 9, just look at the dyno, and they fall off so hard it's pointless to keep reving, people shift as soon as the power starts to fall off, on two strokes when you hit the peak they drop off like your hitting a wall

most modern 4 strokes will pull hard right to the rev limiter

:smirk:

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I'm not talking where the power falls off, I was purely talking RPM's, in terms of which runs at higher RPM's than the other. Which seems to have been the discussion of disagreement. I am well aware of where the power falls off. :smirk:

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