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CRF450R Engine Noise Video Attached

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Hey everyone i just finished rebuilding my 2007 crf450r and it has a strange almost grinding like noise. It DID have this noise before i rebuilt it but i was stumped on what it was. I only put a new set of stainless valves in it and tusk clutch plates and a water pump. Had valves adjusted intakes .006 and ex. .008. Decompressor set right too. I DID notice some piston movement side to side in the bore but the cylinder is fine not scored at all. It still has the cross hatch on it. The piston also rocked a tiny tiny bit. heres the video notice the noise towards the end when i rev it. If somethings wrong i will just tear it down when i get money for christmas

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cam chain has no slack in it the tensioner is fine too the cam chain guides have some wear though specifically the black one

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Im talking about the whirring noise the cam chain guide the black one is worn could that be it... I think the guide is metal

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i know but my other one didt make that bad of a noise it sounds like the cam chain but it is right and i made my own tensioner that is tight idk what it is it sounds bad though could it be the stainless steel valves

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i know but my other one didt make that bad of a noise it sounds like the cam chain but it is right and i made my own tensioner that is tight idk what it is it sounds bad though could it be the stainless steel valves

yea, the ss valves are a bit louder, BUT .. your clearances are all good after the rebuild. SO, the valves are hittng the seats where before if the valve clearances were tight, you would have less noise. These are just loud mo-fos.. heat cycle the engine a couple times and RUN IT. If your builder is decent, it will be just fine. your cam chain guides are NOT metal btw.

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okay im goa take it out this weekend and i think it may be the counterbalancer shaft when i got the bike the water pump shaft and seals were shot so i replaced the whole water pump it almost sounds like a chain going across metal if it were the counterbalancer could i run it like this for a while

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okay im goa take it out this weekend and i think it may be the counterbalancer shaft when i got the bike the water pump shaft and seals were shot so i replaced the whole water pump it almost sounds like the cam chain rubbing if it were the counterbalancer could i run it like this for a while

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The rattling sounds like normal 450 to me. Cam chains make a really loud, awful noise, and you can basically describe the noise as a loose chain.

The whining/whiring noise sounds like gear lash or a bearing is too tight.

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This is exactly what my bike sounded like 20 min. before the piston turned in the cylinder and exploded. Sounds like a worn out piston skirt!:lol:

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yeah te piston was a bit loose in te cylider im just gona throw a new pisto in after christmas i could actually rock it a bit in the bore... i just thought that was what a slipper piston did ad it is all stock besides the valves the clutch basket isvery worn i just grided down the notches that were about 4mm deep could it be clutch chatter

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