What is the valve clearance for a 2005 rmz450

The valve clearance when cold is
intake 0.009 - 0.016 mm (0.004-0.0006) inch
exhaust 0.17- 0.24 mm (0.007-0.009) inch
This is for a 2009 model don't know if engines are same or if they changed following year.

on most engines .06 intake, .08 exhaust

Sounds like a timing issue or simply bD spark plugs. Do a spark check and see if you have a kice blue arc on the plugs. Also I've seen the flywheel key break on those before. That situation will greatly affect the timing Nd cause back firing also check your valve clearance.

the valve clearance may be too tight

the first thing you want to do is check the valves and make sure they are within spec....
if they are tight re shim and put wihin spec

The valve clearance settings for the 2005 RMZ450 when the engine is cold are > Exhaust .006 to .009 > Intake .005 to .007, per the factory service manual.

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The two most important aspects of four-stroke maintenance are frequent oil/filter changes, and regular valve clearance checks/adjustments. And some four-strokes (RMZ450 for example) have a manual timing chain tensioner that must be regularly checked/adjusted. Everything else is exactly like a two-stroke.

i know you have to change the oil and oil filter but how often and is that the only thing different from maintance on a 2-stroke?. Im getting an 04 kx 250f any help would be great!The two most important aspects of four-stroke maintenance are frequent oil/filter changes and regular valve clearance checks/adjustments. And some four-strokes (RMZ450 for example) have a manual timing chain tensioner that must be regularly checked/adjusted. Everything else is exactly like a two-stroke.,,,

i know you have to change the oil and oil filter but how often and is that the only thing different from maintance on a 2-stroke?. Im getting an 04 kx 250f any help would be great!The two most important aspects of four-stroke maintenance are frequent oil/filter changes and regular valve clearance checks/adjustments. And some four-strokes (RMZ450 for example) have a manual timing chain tensioner that must be regularly checked/adjusted. Everything else is exactly like a two-stroke.,,,

i know you have to change the oil and oil filter but how often and is that the only thing different from maintance on a 2-stroke?. Im getting an 04 kx 250f any help would be great!The two most important aspects of four-stroke maintenance are frequent oil/filter changes and regular valve clearance checks/adjustments. And some four-strokes (RMZ450 for example) have a manual timing chain tensioner that must be regularly checked/adjusted. Everything else is exactly like a two-stroke.,,,