Question about CRF450 top end noise

[4504ever]

Well I have about 12 hours on my bike now and the noise I was asking about is still the same so I think it is just a normal sound they make.The bike runs real strong and starts very easy so if there was a problem i think it would have showed up by now.

[strykmaster]

My CRF purrs like a kitten and pulls like a bear. I haven't heard anything unusual from my engine. All I hear is the whirl of the valve train. If you are more familiar with 2 strokes it will sound unusual. That's probably all it is. Ride hard and often.

[therapture]

Originally posted by Woody_CRF
Hmm, appears to be that you are right. BUT, I don't recall any sound from my CRF??? Not that it doesn't make sound, but I've never noticed anything out of the ordinary from the engine.

Compare a CRF450 to a YZF450/426, and you will SWEAR there is something loose in the CRF engine. It is just the way the CRF single cam, rocker arm arrangement, and slipper piston sound. Even my pops, when he first heard my brand new CRF (had a YZF426 before) asked me was something messed up....:

[Woody_393]

hmmm, that's interesting. I really haven't heard anything abnormal, but that's good to know it does make noise???

[jsrheff]

When I first rode my used (new to me) 02' crf450 I was suprised at the clickety clak sound coming of the top end. No weird sounds at idle or goosing in neutral. Mostly hear it coming out of a turn hard, perhaps in too high a gear. But as soon as it gets a few rpm's sound is gone and so am I!

I just chalked it up to the unique sound to this bike. Each of my other 4 strokers had their own unique sound telling me to downshift. I will look into the chain tension clak mentioned, but I'm pretty sure the sound I hear is top end.

[CRF450_RIDERED]

hey
your machine is fine, i promise. lol they all do it

[Woody_393]

Hey CRF450_RIDERED welcome to ATM. Hope to see you often, and posting even more often.

[DonO]

I too was concerned about this "noise" on my '03, so I pulled the top to check vavles (they were fine). I've listened to '02's and '04's and every one is different in top sounds from mine. I think your fine just maybe after ~20hrs of good riding check the vavle clearances to be safe and have piece of mind.

[valverde]

Valves just adjusted and mine still makes alittle noise, but you get use to it.

On my skid plate, I put the sponge material between the engine and the plate as well as some double sided foam stick tape between the skid plate and the frame, bolted it all together and wah lah, still just a noisy, I would have sworn the plate was the culprit.

Just check your chain and get use to it, it's not a problem.

[pragmatic393]

Join the club, I had the same concerns with my 426. Valve train noise.

[kompsj]

It started of as a rattle then got worse. Came from the middle/bottom part of engine, as was evident when you held a screw driver against the engine and the other end against your ear. I changed the counter shaft bearings and noise went away. You should hear a whiring like whistle noise when all is fine and not rattles. I have done about 30 hours of work since and the noise is starting again(rattles) The bearings on the counter shaft sprocket seam to be a mid tolerance type. Might try more precise bearings next go.

[Woody_393]

Isn't the counter shaft bearing lubed by the oil in the tranny side? I think I've heard of this, and also heard (I think anyway, it's all a little fuzzy at this point, so I could be wrong) that it may be caused by not enough oil in the tranny... ?

How are you filling your tranny? Do you use the check bolt or do you measure it and pour it in?

BTW, welcome to ATM.

[Redman450]

I have an 02 CRF450. Before new valves my bike didn't make odd noises. Since the new valves, its almost like I can hear the valves. Sound is coming from the front of motor. I think it could be a exhaust leak from header pipe from when I put bike back together. Gonna check it this weekend. You can hear it with helmet on and my wife heard it when I pulled in after ride.

[Woody_393]

Interesting. Did you find anything out yet?

[desertrider]

My '04 recently has begun to make a very noticeable whirring noise that sounds like its from the top end. Runs great, no discernable difference in power. Thanks to the thread, I did just realize that I started to notice this not long after putting a Devol skid plate on. Maybe it is reflected sound afterall. Occassionally, I hear a kind of rattle that sounds like the cam chain, but it goes away after a few seconds.

[huffdaddy70]

There isn't a dipstick to check the oil in the CRF's like there is in the Yami's?

[fly]

iv got a pretty loud rattle on my crf 450 2006 model... just done a filter and oil change,also gearbox oil... on tickover its real loud like said in the forum it does sound like a sort of chain or tensioner?? i just dont know..and its put me off riding it..i dont want it to blow?????? what do u recon.. can u adjust the tension of the cam chain ...thanks...

[Woody_393]

Their is an automatic cam chain tensioner. They (in the past) were known to back out, releasing tension. Removing it to check is really simple and can give you some piece of mind.

Removing the valve cover and taking a look is really easy too.

If it was mine, that's where I'd start.

And I'm guessing that this noise is when just idling, and not riding, because the chain slapping against the swing-arm protector makes all sorts of racket too.

[yamahammer01]

yea woody is right about the drive chain, i was putting my 450 around the other day and heard the worst sound, and i had read this thread before and looked down and it was the chain slapping aginst the swingarm. but if u never heard it before it can give u a scare!

[2001hondacr125]

Lol im like most of u guys if i hear one little strange sound im all over the place about it. Ask my dad But heres my 2cent i have heard alot of CRFs and they all make this sound at idle, because of the cam, cam chain, valves etc...so if its just at idle i wouldn't worry about it. And usually when the valves do go out of spec like tightening up u wont hear a difference in the sound of the motor (well atleast i didnt) because my intake valves were at .002 Pretty scary when i found out. But shes all good now. But yeah i would say that the sound is the decomp because that thing doesnt have too tight of a spring and it would be flopping up and down in there causing this sound but thats just my 2 cent.