checking/adjusting valves

i have an '03 yz450 and have never checked the valves in it. I have read that yamaha's valves need a lot less checking/adjusting than the honda's but im guessing it should probably be done by this point.

I have never done this before so i was wondering if there is anyone out there who could walk me through, step by step, on how to not only check, but adjust valves as well. Pictures would be pretty cool too.

I did a search on this topic and the only good post i came up with is a valve check/adjustment on a honda 250 but the pictures for some reason wont load on my computer. Im not really sure how differant the process would be from a honda 250 to a yamaha 450.

From what i have read is that checking the valves isnt too bad, but adjusting them is a bit more complicated so thats probably what i would need the most help with.

Also, if there is a thread out there that i couldnt find that already walks through this then could somebody please repost it, thanks.

Try this link http://motoman393.thumpertalk.com/tech/valves.html It is found at the top of this forum under the stickies. We have a lot of great info in the stickies. With this and a manual checking or adjusting valves is nothing to be afraid of.

I have a 04 yz450f that I just adjusted the valves on it. It was a little scary knowing that you have to take the timing chain off for the first time. The only mistake that I made was not writting down the gapping on the three intake and two exhaust valve gaps before I took the timing chain and cam shafts off. Use a magnet to take the shim caps off. p.s. It is a lot easier then you think. This is my first 4-stroke

Take your time and read the steps in the manual.It is really straightforward.About yamahas not needing valve maintenance.I have a 2007 with 8.1 hours on it and i just shimmed both exhaust and 2 intakes.From what i gather a lot of guys seem to do the first adjustment after break in and then get lots of hours before they have to shim again.Also make sure you torque everything per the manual.

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