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Mperry48111

2003 yz450f timing specs

9 posts in this topic

Let's try this again. I do not have a lot of experience with 4 strokes, so I apologize if I am not using the correct terminology. Now, the bike won't start at all. We checked that it is getting fuel. There is spark. When we tried to push start it, we disengaged the clutch and began pushing. After only a few feet, the clutch engaged and everything came to a screeching halt. We pushed in neutral, poped it into gear. Nothing. One last oddity. We opened the oil filler cap on the case. Oil poured OUT of it like it was being pumped out. I'm at a loss.

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The oil pouring out, if it's pouring out while the engine is still, indicates either an overfill or that a lot of gas has gone by the rings while it sat. If it comes out while turning the engine, it may not be so unusual. The bike has a dry sump oiling system, and when they stand unused for as little as 3-5 days, the oil moves down from the frame, where it is stored in operation, to the crankcase.

http://www.thumpertalk.com/forum/showthread.php?p=5221903#post5221903

The probable cause of a no start condition on a bike that has sat around a while is a blocked jet. Then again, you say you have no experience with 4 strokes, so it may be a matter of technique. Two stroke riders all seem to have the same bad habit of cranking on the throttle as they kick, and you can't do that to a modern 4 stroke.

Put a fresh plug in it to start with. Then turn the gas on, pull the choke on, and give the bike 2-3 twists on the throttle. After that, leave the throttle completely closed. Push the engine up against compression, draw back and kick it smoothly through the stroke. If it hasn't started in 3 kicks, try opening the throttle no more than 1/8 and kicking it.

You are going to have quite a bit of trouble getting it lit up in the kind of weather I imagine Michigan is having right now. If you can keep the bike in a heated room for a couple of hours before trying to start it, it will help.

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Let's try this again. I do not have a lot of experience with 4 strokes, so I apologize if I am not using the correct terminology. Now, the bike won't start at all. We checked that it is getting fuel. There is spark. When we tried to push start it, we disengaged the clutch and began pushing. After only a few feet, the clutch engaged and everything came to a screeching halt. We pushed in neutral, poped it into gear. Nothing. One last oddity. We opened the oil filler cap on the case. Oil poured OUT of it like it was being pumped out. I'm at a loss.

I'd change the oil and put the correct amount in before you do anything else. Smell the drained oil, check and see if it smells like gas. Also see if its contaminated with water.

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Thanks for the tips. Drained all the oil. Cleaned the filter. Finally got it started!! After just a little bit of time, the exhaust pipe was glowing red hot, so we shut it down. We are going to get the timing set and see where we go from there. Still have the gearbox issues to deal with, but there is hope for optimism.

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Thanks for the tips. Drained all the oil. Cleaned the filter. Finally got it started!! After just a little bit of time, the exhaust pipe was glowing red hot, so we shut it down. We are going to get the timing set and see where we go from there. Still have the gearbox issues to deal with, but there is hope for optimism.

The headers glow red when they sit and idle, its normal.

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...After just a little bit of time, the exhaust pipe was glowing red hot, so we shut it down. We are going to get the timing set and see where we go from there. Still have the gearbox issues to deal with, but there is hope for optimism.
This is why I asked you what timing you were talking about in the first place. If you mean ignition timing, it isn't adjustable in any way; the components are in a fixed physical position, and the timing is controlled by the CDI unit. Besides, as 642 points out, the red header is what normally happens if you let the bike idle more than about a minute (less in low light). Right after that, it should start blowing coolant out the overflow tube. They don't like idling at a standstill.

Cam timing is the only event timing that can be set on the YZF.

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