Argh ticking noise from engine. Help me identify (sound file)

[t3rmin]

Got a ticking noise coming from my motor.

It's not really audible unless you put your ear to the gas tank. I've already used a hammer as a "stethoscope" all over the motor and unfortunately can't seem to pinpoint a specific region.

So I'm hoping somebody can identify the noise by listening to this sound file. Top end? Bottom end? What is it???

You'll hear me start the motor, put the mic to the tank, blip the throttle, rev it good, let it idle, then shut it off.

http://thetrents.org/files/bike%20noise.mp3

[Tarbash 27]

It kinda of sounds like a loose timing chain. I worked on an atv last summer that sounded exactly like that. The tensioner had no tension on the timing chain. The chain was loose. I fixed it up so it had tension, worked perfect, no more sound. But get some other opinions.

[t3rmin]

Thanks bro. Haven't been into the tensioner yet so it's entirely possible. Any way to check that without removing the tensioner?

Anyone else?

[bradleymaynar]

It could be the auto-tensioner. bwringer has a great rebuild series, but, unfortunately, I don't have the link. You may want to PM him.

Brad bt

[t3rmin]

It could be the auto-tensioner. bwringer has a great rebuild series, but, unfortunately, I don't have the link. You may want to PM him.

Brad bt

Yeah it's a very nice guide -- I've probably already got it bookmarked somewhere. ;-)

So that's what it sounds like to you?

[bradleymaynar]

Yeah it's a very nice guide -- I've probably already got it bookmarked somewhere. ;-)

So that's what it sounds like to you?

Crap!:shock: I hadn't listened to the clip. My opinion here, but it could be something in the oil pick up tubes in the pan. I only say this because our Buick had a very similar problem that ended up being a tube that had managed to get into the crankshaft. We ended up getting a new engine. I'm not saying that this is what your problem is, but the sound is very similar. Definitely NOT a cam chain problem IMO! I would strongly suggest you not ride it until you figure this out.

Brad bt

[t3rmin]

UPDATE: I went out and paid closer attention to the ACCT. I can feel/hear a pulsing in the knurled knob which seems consistent with the noise. So that must be it.

*EDIT*: Now I'm not so sure. I can hear/feel it in the clutch actuation lever (at the motor) strongly as well. And I messed with the tensioner a bit and couldn't make the noise change. However, after using a screwdriver to listen all over the motor it's strongest in the middle chain tunnel area. So I think it must be either the camchain, something else in the valvetrain, or the clutch basket...?

[tconroy]

A noise like that you should be able to put your hand on the cam cover and be able to tell if it's coming from there.If it's moving your shift actuation lever then it's got to be in the clutch basket.It's hard to tell from just a sound bit.Have you checked the oil level?Just a thought.That thing's really banging.It should not be hard to tell where it's coming from.I just rebuilt my cam chain tensioner and the parts where only 7 bucks.The knurled knob does not move at all like you discribed when the engine is running.

[t3rmin]

Oil level is good. I know it sounds like a big nasty bang, but like I said, you can't even hear it unless you put your ear on the tank. It's really a mild noise but the tank seems to amplify it well. If you notice when I first start the bike, before I put the mic on the tank, you can't hear it at all.

Could this be the cam endfloat knock I've heard about?

[denydog]

Are you sure it's not a really loosely adjusted valve? It kind of sounds to me like it's at a similiar speed of a valve opening. But I'm only guessing.

[KEITH KRAUSE]

Funny how you say it's hard to hear if you're next to the bike. It sure sounds loud in the audio.
Sounds like something related to a valve tappet with excessive clearance. The "ticking/clicking" is the right pitch and the rhythm/rpm's seem to match too. Seems too high pitched to be in the bottom end. Just my opinion.

[tconroy]

Is your tank full of gas? If it was cam endplay you would only here it at an idle.Does it go away when you let out the clutch.It sounds like it is in time with the motor, maybe a tappet problem.I think the cams and crank only turn at half engine speed so I would say its something that turns at engine speed .What about the stator?Maybe a bad tachometer gear?Is your tach bouncing.Just throwing out ideas.

[t3rmin]

Good ideas!

I have adjusted the valves recently but it's possible I royally screwed one up or something. I agree that the timing makes it sound like something valve related.

I'll have to try running it without the tach gear to eliminate that one.

The noise isn't affected by working the clutch.

Keith: I'm glad to hear someone say it doesn't sound like bottom end!

Yeah it does sound really loud in the recording. And it sounds about like that when you put your ear to the tank. However, it's so quiet as to be almost completely inaudible otherwise. For whatever reason the tank does a great job at amplifying it.

[49er]

Oil level is good. I know it sounds like a big nasty bang, but like I said, you can't even hear it unless you put your ear on the tank. It's really a mild noise but the tank seems to amplify it well. If you notice when I first start the bike, before I put the mic on the tank, you can't hear it at all.

Could this be the cam endfloat knock I've heard about?

It's definitly not excessive cam endfloat knock. Many others on this forum can confirm this.

When you placed the mic against the tank, was it on top, or was it touching the side of the tank and also making contact with part of the engine (cam cover)? If it was touching both, the mic will be picking up noises from the valves/cams/chain/head area.
Half way through the sound clip, just after you attach the mic to the tank, the sound rises and falls, sounding as though the engine is trying to stumble but then regains its rhythm.
Apart from a seriously loose valve, the only time I have heard a similar sound, is when a small piece of head gasket has blown out between the head and the barrell. This will also cause the engine to stumble at and slightly above idle. A badly leaking exhaust flange gasket will also give a rhythmic ticking sound as well.

[tconroy]

If you have adjusted the valves recently I would pull the cover off an inspect everything to make sure you did not make a wrong adjustment in clearance settingsIf you put your hand on the engine where can you feel it tapping?Did you replace any shims?It does sound like it is in the top end for sure.