Strange engine sound

[wheatonFJR]

Definitely does NOT sound like a loose cam chain.

Dead mouse in the air filter?

I don't know that sound. I do know the camchain sound.

[FJRoss]

Maybe not a dead mouse but worth pulling the air filter to see if anything is in there or if one of the "snorkels" came off the airbox and is rattling around.

[raYzerman]

Left side of engine is #1, correct. TPS switch is on the left end of the throttle bodies.......
The red plug is likely from removal of the PAIR system hoses and solenoid....... above that, is that the folded up insulation pad???

I can't tell you what that noise is, sounds to me like more of a knocking noise. I'd really need to be right there to give a better opinion......
Not much there where you're pointing your screwdriver, that is the air intake from the airbox before air goes to the throttle butterflies.. can't think of anything that would knock.... in that area.....
Except a bad injector, but that would be more of a ticking noise. Could the noise be up further at the valve cover?

IF that is the insulation pad I see, you really should lift the tank, prop it up and get the T-bar and insulation all out of there so sound is not deflected, etc., then get a piece of hose and listen at various places, maybe another sound byte/video would help. You took the video through holes in the fairing... hard to tell whazzup. So, if you can, get that from the top also.

I'm guessing it is not cam chain related/CCT as all that is on the right side. That's the good news.

[raYzerman]

Just listened to #3.... well that is a little different, but...... lift tank, yadda yadda.... do it again.

[raYzerman]

Additional questions.... is this noise only when cold and goes away or gets better/worse when hot?
Watch for hot surfaces, but while still relatively cold, can you feel the top of the valve cover with your fingers at various places and also check if any particular injector is "knocking" significantly worse than the others? Just trying to nail down actual location where it's loudest.
Is there any foreign object lodged between the valve cover/cylinder head and the frame? Flashlight time.....
You could pull the air filter and check for mouse nest/foreign material at that intake, but I'm kinda not thinking so, can't hurt to look. I don't think anything can get past the inside of the filter.......

[Festus]

Loose spark plug?

[BkerChuck]

Loose exhaust hardware? Sounds somewhat like an exhaust issue to me. In the late '80s I had a FJ1100 and those bikes had a double walled exhaust header. After several years and quite a few miles I had some of the header pipes break down internally and the welds holding the outer and inner pipes broke loose. It developed an odd rattle that sounded somewhat similar to that.

[wheatonFJR]

I'm guessing Marty put something on your bike to make it rattle. I know he's do it in a heartbeat...bastard.

Seriously, hope yer able to find the root cause soon...and hoping it's something silly.

[bungie4]

I'm with Ray on this one, that sounds like a light knock. It actually sounds like a double knock, that would be a rod bearing, but let's not go there just yet simply because it doesn't seem to vary with engine speed.

Pull off your lower fairing and redo the sound test. Stop jerking around. While the fairing is off, give your exhaust system a good inspection. Lost our missing header bolts, cracking around the flanges, and around the cross over...

[raYzerman]

Loose spark plug seems plausible too..... but I'll await an update.
I don't think it's exhaust (yet).

Don't worry, Josh, we gotcha covered. Take it to Geek's tech day, those guys are more than capable of breakin' shit.
I gots spare engine parts.......

[Hppants]

I like the idea of using a hose or screwdriver on the cam/valve cover. I think it sounds like something is loose under there (possibly cam bearing bolt loose??).

IIRC, the oil drain plug is magnetic. Maybe pull it and see if there is any metal on it.

We (via facetime) did look over the header bolts but honestly, ya'll know ya gotta take the fairing off to get a GOOD look at it. Also agree with Ray - prop the tank way up, remove the insulation and T-handle, etc -maybe put a piece of cardboard on the RIGHT side gap between the bike and the raised fuel tank. Really try to focus the sound toward the microphone. Which is another issue - the phone mic is not too good for this. But I played around with my own phone last night and found that if you cup your hands around the mic to simulate the "bull horn effect", the mic for the phone is MUCH better. So maybe after you get things situated, try another video whereby you do this - recognizing that the VIDEO from that will be useless, but the AUDIO might offer more clues.

Wonder if the SENA helmet microphone would pick up the sound better, and if so, how can you record that input and get it to a digital sharable format?

This noise is metallic or hard plastic in nature. I don't think a soft mouse next (or dead mouse) would make a noise like that.

The noise manifest itself at idle. No point in free revving it and potentially damaging it further. Although if it is an internal metal part (heaven forbid), I suppose the damage is already done.

Get busy brother - riding season is almost here for Pants!!

[extrememarine]

I would suggest a thorough visual inspection under the tank before attempting any more sound recording. Rule out any free fixes (loose fasteners, spark plugs, air box, etc.). If there is something bad wrong inside the motor, I'd suggest minimizing the amount of run time as mush as possible.

Checking the oil drain plug for material is a good nearly free check as well to help narrow down the issue.

[Festus]

Loose PAIR plate? To me, the sound of the exhaust is not normal. Sounds like a hint of Yamaha YZ-125 in there. Almost like the exhaust sounds if coming out before hitting the pipes.

My guess is something is loose or a hose has come off and it's going to be a 2 minute fix when you find it.

[extrememarine]

knock, knock?

any progress on getting under the tank to check suggested items?

[Cav47]

knock, knock?

any progress on getting under the tank to check suggested items?

I have been slacking some. But getting home after supervising baseball and softball games as well as cross country meets has me stretched a little thin for time.

Truth be told, I am a little scared of what I am gonna find in there. Or rather I am a little scared of not being able to find anything and then not being able to put it back together like I should.

[FJRoss]

One step at a time. I would start with the easy (and minimally invasive) stuff. Check the air filter and make sure nothing is loose in the airbox. Check the joints where the cans connect to the header and where the header connects to the engine. Could it be something as simple as a broken weld for one of the baffles in the exhaust? Or even a busted up cat? Aftermarket exhaust or OEM?

[blind squirrel]

Truth be told, I am a little scared of what I am gonna find in there. Or rather I am a little scared of not being able to find anything and then not being able to put it back together like I should.

Sounds like Cav is trailering his bike to Geek's tech day.

[raYzerman]

knock, knock?

any progress on getting under the tank to check suggested items?

I have been slacking some. But getting home after supervising baseball and softball games as well as cross country meets has me stretched a little thin for time.

Truth be told, I am a little scared of what I am gonna find in there. Or rather I am a little scared of not being able to find anything and then not being able to put it back together like I should.

You are making this too complicated..... lift the tank, get the insulation pad and t-bar out of there..... get a flashlight, look around, then fire it up, take your NEW video.... feel around for noise, use a piece of tubing as a stethescope. Just nail down the location and sound......
Check your spark plug coils are seated.

[wheatonFJR]

knock, knock?

any progress on getting under the tank to check suggested items?

I have been slacking some. But getting home after supervising baseball and softball games as well as cross country meets has me stretched a little thin for time.

Truth be told, I am a little scared of what I am gonna find in there. Or rather I am a little scared of not being able to find anything and then not being able to put it back together like I should.

I know the feeling. Been there.

[bungie4]

Analysis paralysis.