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Breaking in new bike

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Well still waiting for my new 05' crf450. This will be my first honda four stoke and wonder what is the best process

for breaking in the motor?

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I'll be getting the same bike soon, maybe Tues. I've heard let it warm up alittle, roll throttle on slow, shut off throttle complete, don't roll off the throttle. Also heard from a pro, T. Fowler, (He took 2 second place world titles some years ago), just ride the new bike, don't worry about break in, there not like the old bikes. I think I'll take it easy on my machine the 1st tank full, not let it get way hot. I'm new to these newer machines thou too :cry:. Let me know how it goes. Good choice.

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Well still waiting for my new 05' crf450. This will be my first honda four stoke and wonder what is the best process

for breaking in the motor?

Just ride it, don't follow what the book says. There is a web site floating around that advocates running it HARD as an effective way to break it in. I don't have the URL handy.

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Don't baby it. DO NOT baby it. DO NOT go easy on it. RIDE it...

Use full throttle openings (which is different from hitting the rev lmiter) which creates cylinder pressure to seat the rings properly, and then let the bike use engine breaking to slow down (don't pull in the clutch when slowing down).

Ripped from the moto tune website...

What's The Best Way To Break-In A New Engine ??

The Short Answer: Run it Hard !

Why ??

Nowadays, the piston ring seal is really what the break in process is all about. Contrary to popular belief, piston rings don't seal the combustion pressure by spring tension. Ring tension is necessary only to "scrape" the oil to prevent it from entering the combustion chamber.

If you think about it, the ring exerts maybe 5-10 lbs of spring tension against the cylinder wall ...

How can such a small amount of spring tension seal against thousands of

PSI (Pounds Per Square Inch) of combustion pressure ??

Of course it can't.

How Do Rings Seal Against Tremendous Combustion Pressure ??

From the actual gas pressure itself !! It passes over the top of the ring, and gets behind it to force it outward against the cylinder wall. The problem is that new rings are far from perfect and they must be worn in quite a bit in order to completely seal all the way around the bore. If the gas pressure is strong enough during the engine's first miles of operation (open that throttle !!!), then the entire ring will wear into

the cylinder surface, to seal the combustion pressure as well as possible.

The Problem With "Easy Break In" ...

The honed crosshatch pattern in the cylinder bore acts like a file to allow the rings to wear. The rings quickly wear down the "peaks" of this roughness, regardless of how hard the engine is run.

There's a very small window of opportunity to get the rings to seal really well ... the first 20 miles !!

If the rings aren't forced against the walls soon enough, they'll use up the roughness before they fully seat. Once that happens there is no solution but to re hone the cylinders, install new rings and start over again.

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Exactly what they all said....

I have had many dirt bikes and many street bikes. I never worry about break in. I let it warm up really good, ride it hard and then change the oil after the first ride. My friends say i am doing it all wrong, but then, my bikes always make more power and run better than theirs. And we all pretty much hav the same bikes.

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