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Difference I'm jumping 4stroke vs 2stroke?

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Now that I have a yz250f I have to learn the differences in jumping. I see some videos where when they are I'm the air they pin it and hit the tve limiter others don't.. So what's the correct day to junp a 4 stoke motorcross bike?

1993 Kawasaki kx125

2004 Yamaha yz250f

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Now that I have a yz250f I have to learn the differences in jumping. I see some videos where when they are I'm the air they pin it and hit the tve limiter others don't.. So what's the correct day to junp a 4 stoke motorcross bike?

1993 Kawasaki kx125

2004 Yamaha yz250f

There is no benefit in hitting the rev limiter on a 4 stroke, especially in the air. I think kids do it because they think it sounds cool. But it will shorten the engine's life big time. Here's a brief description on the differences between 2 and 4 strokes: Ever since sometime in the early 80s two strokes have put to good use the development of a power valve in the exhaust port.  This power valve has smoothed out the hit of the two stroke’s power band a great deal.  But in order to get a lot of horsepower out of that two stoke engine they still have a certain amount of hit to the power band.  This is the biggest difference between the two and four stroke.  The four stroke is just smooth tractor like power right off idle all the way upstairs.  This is why the four strokes depend less on the clutch and more on throttle control.  You don’t have to help it into the power with the clutch nearly as much as with the two strokes. 

 

The other difference is with engine braking.  When you’re going down a straight away and you shut off the throttle on a two stroke the back pressure from the engine will slow you down a little, but on the four stroke this engine braking is much stronger.  This will make the Exit Dex of a corner (where you go from braking to accelerating) easier.  You don’t have to be quite as precise with the brakes.  This engine braking effect will affect you on jumps too  because if you roll the throttle off on the take off of a jump it will throw the front end down much more on a four stroke.  This won’t be as noticeable if you’re in a higher gear. 

 

Since you don’t have to be as precise with the clutch and throttle and the brakes on a 4 stroke they are easier to ride. 

 

At this point in time that’s the main differences between the 2 and 4 strokers.  The actually riding techniques are the same.  The way I see it it’s all good. 

 

All the details for the clutch, throttle and shifting techniques are shown in this DVD, see a free preview here; http://wp.gsmxs.com/dvd-3-clutch-throttle-clutch-control/

 

<iframe src="http://cloud.ezwebplayer.com/iframe.htm?v=6EyxwSe&w=695&h=521" style="border-width:0;width:695px;height:521px" scrolling="no" allowFullScreen></iframe>

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The same as a 2 stroke man, I still have my old 125 too I ride it every time I hit the track and I do every jump I do on my 250f. The big difference is the feel in the air with the 2stroke it's like your riding a mini bike after the 4 stroke it's just way lighter super easy to maneuver in the air compared to the 250f. Back in the day I would run my practice laps on a 450 then race my 125.

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