low grinding sound

[dfpextraordinaire]

Oh my gosh, I just got back from Carson City and slid my new blue baby out of the garage to wash her cuz she has been sitting for a week and when I started her up and gave her a little gas as soon as i did she kinda had this low sounding grind in the lower part of the engine. I thought that I must be nuts, went over to see my neighbor who has an 06 also and asked him to come and take a listen... at first he didn't hear it. We went over and started his while it was cold and when we gave it a bit of gas, like a blip no sound like mine. Back to my house and did the same thing, he just looked at me and said, maybe you better take her back to the dealer and have him take a look-see. This bike has 2400 miles and has been like a dream but the sound freaks me out. I let her run for a bit and when she was warm it was less noticable but still there even though slightly.

Any of you really, really smart guys out there have a clue about what this may be or is this "dumb ******' painter" just worrying about nothing?

Help!!! :clapping: :clapping: :clapping: :clapping: :clapping: :angry2: :angry2: :angry2:

 

[C&C]

If you try to rev the engine before it warms up sufficiently you may get a gutural kind of stumbling sound (this is normal). If yours is more a mechanical sound you probably need to have it looked at.

 

[ionbeam]

Here is something that may be good news! Ride your bike until it is completely warmed up, say 5 minutes after the thermostat opens up and then give it a listen again. When your bike is cold it activates an air injection system that uses reed valves to put air in the exhaust right up where the head pipe bolts to the cylinder head. The purpose is to add air (O2) to the exhaust for a secondary burn to ensure that during choke operation (cold enrichment) excess HCs get burned off. The air injection will stay on sometimes even a little past the thermostat opening. A byproduct of the air injection can be an almost diesel type noise that you may hear as grinding.

If you are the intrepid type you can take a long metal rod and put one end on a header pipe and put your ear to the other end. You will be amazed at what you can hear! Now move the 'hearing aid' to the lower part of your crank case. You will positively be able to identify the area of the noise.