simple question

im new to the liquid cooled bikes and nobody on this forum has givin me the answer to my question hope you guys can help me out :thumbsup:

my brand new 04 yz450f motor(engine noise) is really noisy is this normal?

it is a lot noisier than my xr 600

are you talking all around more noise, or to a specific area of the engine? I imagine you have checked your oil level, a low level could make the engine noiser if certain parts are not getting enough oil ie... valves, bearings.

they arent the quietest motors around. make sure you arent confusing the engine noise with chain noise.

they arent the quietest motors around. make sure you arent confusing the engine noise with chain noise.

yer, I thought my motor was real noisy, but turned out to be the chain. I put some foam under the chain guide, that made a huge difference :thumbsup:

Welcome to the liquid cooled world. The new engines use much thinner and lighter materials than the old air cooled engines. Due to the nature of the valve cover you can hear alot more valve train and cam chain noise, it's normal. Definitly put some foam under the chain slider on the swingarm, open up the exhaust and let it rip. Free mods are woth it. Good Luck-WR Dave. :thumbsup:

who has the link to the foam under the guide info.

mine is starting to piss me off. thx.

I can't find my link for it, Very easy to do, just take the chain slider of, clean the surface, i used The foam that you use between doors to seal it if there is a gap. It has a sticky surface on one side, just lay it down where the slider sits, then put the slider back on. I only done mine last month. Not to sure it will last long though.


on the bottem or the top?

Put the foam on the top side of the swingarm, between the swing arm and the chain slider.My foam has been in there for 3 years and is still working. Just make sure it is in there good and tight when you put the slider back down. Also take a small socket and tap the slider bolt washers down to capture the slider more securely. I bought a new UFO (I think) slider when I bought the bike in '02 , because everyone said they wore out and that new slider is still in my cupboard. The info will be on Motoman's link and at( ). Good Luck --- WR Dave. :thumbsup:

Found it, check this out. Go to tech articles, and under the Misc heading click on "Fixing the YZ's faulty swingarm slider"


both. an old inner tube cut up works also.

Wow Thanks !

yeah i know the chain is really noisy but the noise is in the cylinder i can hear it when im just idleing the bike in the drive way well im gonna take to the dealer the told me take it after 10 hours anyways while its there im gonna ask them ...

My WR450 is what I would classify as *REALLY* noisy in the engine. The motor is thin walled and every mechanical sound in that thing you can hear when it is running. I though it was a problem with the bike too, so don't feel to bad. I have about 1000 miles of hard offroad use and it is just fine. I noticed that after a few hundred miles some of the noise seemed to quiet down or maybe I just got used to it. Anyway, take the exhaust plug out and you won't hear the engine anymore and it will run better. Have fun with thatr YZ450...

try going for a ride without a helmet on (slow of coarse) and u'll be amazed that something can make that much noise and still survive!

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