Question About Valves??

4 replies to this topic
  • bigwake

Posted August 03, 2007 - 08:12 PM

#1 i've asked just around 1 billion questions on here so what's one more? i just got my first 4 03 yz450f..all i have owned in the past were 2 strokes..never rebuilt any..never had any problems with any of i keep hearing about valves valves valves on these 4 bangers..when i bought this thing i had just begun hearing about them..i have not checked the valves on this bike..the people who owned it before me were some hippies from california..they road est. about 50 hrs of desert trails and moved to florida where it sat for 2 yrs bascially..he did start it and try a local spot and was chased off...the guy riding it was a kid with his dad..the dad said the son really wasn't ready for such a bike..and he did dump it sometimes..both radiators were torked..not leaking..but i did replace them..i $1600..i could afford some the bike started first cold kick at his house..(i felt the engine before he kicked to see if he had it running earlier..he hadn't)..and it ran like a dad test road it for me down the street and pulled a wheelie on the old chain that had about 7 inches of slop on we finished the i have had noo problems with this bike..and wondered if i could get away without checking the starts soo easily..1st kick everytime!! hot or cold! i taking aHUGE risk by not wanting to open my engine and check valves? or is it not too risky?..and yes..i changed the plug first thing..and oil filter with gaskets..and rad fluids..and air filter..and am i ok? really?..thanx-josh

  • grayracer513

Posted August 03, 2007 - 08:37 PM


The only risk in checking your valves is that you might misposition the cam cover gasket on the way back together. Adjusting them is somewhat complicated, but not especially difficult if you pay attention to all of the details.

Being what it is, the odds are that it's a long way from needing a valve adjustment. But, without checking, you have no idea, and neither does anyone else.

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  • bigwake

Posted August 03, 2007 - 08:41 PM


ok..i'm leaning towards just leaving them alone..i mean..for me it's no REAL biggy..i know that the engine has never been it should be tight in there..and when i sell it i can say that "iv'e never had her opened" gray..what types of signs should i look for in pre-valve trouble?

  • grayracer513

Posted August 03, 2007 - 08:43 PM


If you see any signs, like a loss of compression when cold, it's essentially too late. Check them.

  • bigwake

Posted August 03, 2007 - 08:45 PM


ok will do! thanx again!

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