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04 yz450f

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hey all my name is erick, I am new to the forums. i just picked up a 2004 yz450 F and now i just have a couple of questions. I been out of the MX game for about 4 years, never owned a 4 stroke, I was a 2 stroke kind of guy, i raced an RM125. I am just wondering. I was going through the gears on the bike and it feels like it only has 4 gears is this accuarte? also what kind of oil are you guys running in this beast as i dont have an owners manual. and this being my first 4 stroke, what are the goods/bads on this bike? is it a good MX bike?

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Congrats on your new bike. Yes your bike is a 4 speed, 2003 through 2005 yz450's were 4 speeds. Everybody runs different oil in their bikes, that's more of a personal preference so just pick an oil you like and change it often. Look at the sticky threads at the top of the page and you should be able to find a download for the manual and A LOT of other good information about your bike. Yes it should be a great mx bike, that's what it was made to do.

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Yes, it only has 4 gears.

Here's a link to a service manual download:



To a summary of the oil change procedure:


And to the Common Threads Sticky:




Avoid automotive oils that are marked "API ECII" or "Energy Conserving II", as these have potential to cause clutch problems. Otherwise, know that most automotive oils lack the ability to stay in their graded viscosity for more than about two hours when used as transmission lubes, and since the YZF shares engine oil with the trans, plan on changing oil pretty much every ride day if you use one. 10w-40 is adequate for most conditions, but if it stays above 90 most of the time, a 20w-50 is more to my liking. Other information about oil requirements is in section 2 and 3 of the manual.

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