Engine whistling at 5000 rpm

[Longhaulpaul]

I started hearing a whistling noise, kind of tinny vibration while riding and first thought it was in my audio equipment or helmet, but finally narrowed it down to actually coming from the engine, consistently and only at about 5000 rpm.

Bike is a 2012 with 56,000 miles. Noise seemed to start a few weeks ago.

Any thoughts?

Thanks.

 

[HHH]

Does it sound like gears singing?

 

[EricV]

When was the last time you checked your airbox drains? Maybe one of the caps got pushed off?

Other than the noise, how is the bike running/idling? If there was also an idle issue, irratic or high, I'd be looking for vacuum line leaks.

The only other thing that comes to mind would be air stream dynamics. Has anything been moved/bumped in regards to the windscreen, headlight guard, wind deflectors, etc?

Naturally, it's also time to question if you have done anything to the bike in that time frame too. Always good to look over the last thing you did, or had done. I've seen the two vent lines from the tank be forgotten to be clipped in down below and then flap around. I could see those whistling under the right conditions as air flows over the ends. OR being crimped/pinched when the tank was put down, so pressure is building from the tank, then venting oddly at some point.

 

[Longhaulpaul]

I recorded the sound, it really is starting to sound to me more like a lighter weight bearing noise, maybe water pump?
Only happens at 5,000-5300 rpm. Happens every time. Even stopped or in neutral. No other abnormalities in engine noise. Runs fine otherwise.

Here is a link to the audio file. It didn't come out great,
I have a cleaner MP4 file as well.

https://app.box.com/s/jysmygx8sjw1oppi3k8n

 

[~TABASCO~]

I agree. Not normal. Give the dealer a shout !

 

[spklbuk]

Could it be coming from the holes in the skid plate as the wind harmonics through? Just a random thought without listening to the sound file.

 

[Longhaulpaul]

Yeah, about that. Dealers around here say "Nice BMW".

 

[Longhaulpaul]

No skid plate. No wind while stopped around here either

 

[HHH]

I had some weird noise on mine, turned out it was the OEM wrenches vibrating inside of the tool kit...: