Engine Noise, HELP!!

[jftoha]

I hope someone can give me some peace here. I have a 2007 S2R1000 that has 6,500 miles. As the temperatures have gotten higher here in DC, the temperature of the bike has reached the typical 230 to 260 in stop and go traffic when it's hot outside. A couple of days ago i noticed that once the engine reaches those temperatures, the Engine has a fairly loud rattle coming from what looks to be the heads/Valves area. When I first heard it, it reminded me of my 2003 620 which also made a similar noise once it got around 230-260. Now, I am fairly sure that on the 620 as in the S2R 1000, the noise only became evident after the bike reached some milage. I sold the 620 when it had about 8,500 miles but I remember noticing the noise for some time before I traded it  in.  It is worth noting that if I go for a ride in a clear road and the bike only reads about 190-200 the noise does not come up.

At all times the bike runs strong and perfect and I can only notice the noise when I am still and the bike is running at idle. The oil was changed about 500 miles and is not running low at all. Since it is a 2007, I am not due for a Service 2 for another 1000 miles. But I have changed the oil twice since the 600 service. I am considering taking it for the 7,500 mile service because I do not really trust the extended services much. Could it be the Valves are due for an adjustment? Why would they only rattle at very high temperatures?

Any ideas?!!

[Popeye the Sailor]

You'll get better replies if you move this to the "tech" section. There should be an option at the bottom of your screen.

[Drunken Monkey]

Or an admin will move it for you 

Is the rattle more pronounced on the gas or is it constant, happening even at idle? Does it keep pace with RPMs?

Is it worse when you lug the motor at low RPM or is it louder at high RPMs and low throttle settings?

Just trying to distinguish between a myriad o possible causes....

[silentbob]

Maybe you are hearing the fins ticking at high temps.  What is the frequency?  Is it rhythmic or random? 

Is it under load at low rpms?  If so you are probably just pinging.  Try a higher octane gas.

[jftoha]

Is the rattle more pronounced on the gas or is it constant, happening even at idle? Does it keep pace with RPMs?
The Rattle is only noticeable at idle, at least I can only notice it at Idle.

Is it worse when you lug the motor at low RPM or is it louder at high RPMs and low throttle settings?
It goes away as I rev the engine passed about 1600-2000 rpm or so. So, it's at its loudest when at idle.

Just trying to distinguish between a myriad o possible causes....

[silentbob]

Is the rattle more pronounced on the gas or is it constant, happening even at idle? Does it keep pace with RPMs?
The Rattle is only noticeable at idle, at least I can only notice it at Idle.

Is it worse when you lug the motor at low RPM or is it louder at high RPMs and low throttle settings?
It goes away as I rev the engine passed about 1600-2000 rpm or so. So, it's at its loudest when at idle.

Just trying to distinguish between a myriad o possible causes....

At idle in neutral or at idle while letting the clutch out?

[jftoha]

Maybe you are hearing the fins ticking at high temps.  What is the frequency?  Is it rhythmic or random? 
It's rhythmic as if it's a moving part of the engine making the noise.

Is it under load at low rpms?  If so you are probably just pinging.  Try a higher octane gas.
Once I am moving under load I cannot hear it. I can't only notice it when I stop at a light or when i park. An it only happens when the engine reaches about 230-260 degrees which mean only after stop and go traffic or getting into a traffic jam on a hot day.

[jftoha]

At idle in neutral or at idle while letting the clutch out?
Both, and it makes no difference if the clutch is engaged or not. Only revs or letting the engine cool down will make it go away. also, if i get out of traffic and the temperature goes close to 200 the noise will stop. Now, the engine noise maybe more of a mix between internal rattle and tapping.

[monsta]

when you rev it, do you think the noise is just going away because its getting drowned out by the noise of the engine?

[A.duc.H.duc.]

At idle in neutral or at idle while letting the clutch out?
Both, and it makes no difference if the clutch is engaged or not. Only revs or letting the engine cool down will make it go away. also, if i get out of traffic and the temperature goes close to 200 the noise will stop. Now, the engine noise maybe more of a mix between internal rattle and tapping.

Metal expands when it gets hot. It's possible you're just hearing a little more valve noise because parts have expanded and are resonating the sounds better.

Does the sound drop off completely when you rev the motor or is it possible it is just lost in the rest of the noise of the motor?

Also, what weight oil are you running? Heat thins oil, so maybe you're just heating it to the point that the oil has thinned enough to let the parts rattle more.

[silentbob]

record some audio and post it up.

[battlecry]

jftoha:  I hear the same on my '03 M800.  Pretty noticeable rough rattle at idle when really hot.  Bike runs fine otherwise. 

[jftoha]

I'll do that tomorrow. Hopefully that will help. I will record it before it gets hot, when there is n noise, and after.

record some audio and post it up.

[jftoha]

I read an old post where somebody also had the same issue. Even though I hate the sound, i really hope it's normal.

jftoha:  I hear the same on my '03 M800.  Pretty noticeable rough rattle at idle when really hot.  Bike runs fine otherwise. 

[battlecry]

No question these engines do not like running hot.  When I did the valves, the exhaust valve/cam cavities had the burned varnish look to them of overheated oil. 
I got so concerned once about the rattle I thought the center electrode insulator might have broken off and pulled a plug.  Found the electrode and ceramic fine but what looked like pits from foreign object damage in the face of the horiz piston.  Have no idea how that could have happened. 

I checked and adjusted the vert cyl belt tension on the looser side, in case it gets too tight with heat.   That and good oil changes.  No other good ideas, I'm afraid.

I learned to think of it as my bike's faux dry clutch rattle.     

Rolling Thunder was an exercise in starting/restarting to avoid heat and clutchwork.