very irritating harmonic rattle

[3W-lonerider]

iv'e had a very irritating harmonic rattle for the last couple of months now. been trying to track it down. this rattle was loud enough it would actually drown out the stereo and exhaust pipes. very loud and irritating.
it would vibrate and rattle mainly between 1800 and 2300 rpms. it would vibrate and rattle at any rpm if you were climbing a hill.
seems like it would mainly do it if the engine was under a load.
if i was cruising along it would be fine. if i gave it some throttle it would vibrate and rattle. as soon as i left off the throttle it would go away.
i knew it was'nt the buzz bolt because when i installed a new thermostat 2 years ago i installed set screws in the spacer bar.
i knew it was coming from under the seat or the rear of the engine somewhere and it was mostly on the left side.
was'nt possitive on that mainly because of the way my hearing is.
so heres what i did. i started removing covers one at a time. started the bike. hold the brake and give it alittle throttle and started releasing the clutch. it was'nt until i removed the left side tranny cover. that i discovered it. when removing the cover my finger hit the bracket for the altenator cover that goes around the alternator.
 it went twang. and sounded almost the same pitch as what iv'e been hearing.
 installed the alternator bolts into the holes without the cover on and done the same test.. vibrating noise gone. put the cover back on and vibrating noise was back

figured out that even when the 2 bolts going threw the top of the alternator was tight that the bracket behind it was'nt getting tight.
the bolt that holds the front of that tranny cover on was keeping the tranny cover from getting tight in the rear , so i put a couple peices of sound proofing material between the bracket and the alternator plus the tranny cover and the bracket.
put everything back togather. no more irritating vibrating rattle..WOO-HOO.

[97BLKVALK]

I have that same noise.  Will be checking it out tonight.

Thanks

[Kep]

I was having similar noise but it was my chrome radiator ends. Put some double-sided tape under them and cured it !

[cef2lion]

I have been hunting a buzz noise and thought I had checked the left covers. I had replaced the alternator cover as the lower mount was broken. I checked the covers last night. The front of the tranny cover wasn't tight but the bolt was. The rear tranny cover bolts were keeping the alternator bracket on mine tight. I left the alternator and tranny covers off and took a ride.

The buzz noise I had under load or under throttle was reduced greatly. I'm going to add a washer to the front tranny bolt and see if that gets the cover tight.

I still have a slight buzz from another location but it isn't as bad as this one. I have tapped the buzz bolt tube with set screws so I know its not that. Tried running with the radiator grille off. Going to pull the right covers next and see if that helps.

[3W-lonerider]

keep in mind..just because the 2 rear bolts going threw the tranny cover was tight does'nt mean that it's keeping that alternator bracket tight.
my 2 bolts were tight and seemed well seated but with the front bolt installed the bolts were getting tight to the cover but could'nt push the cover any farther forward because of the front bolt.. easiest way to check it would be to remove the front bolt and re-tighten the 2 rear bolts and see if the front mounting bolt isn't about 1/8th off. if you can't get that front bolt in after tightening the 2 rear ones then your leaving a gap between the alternator and the cover so that bracket can sit in btween there and vibrate.

[cef2lion]

I'll do as you suggested and tighten the rear cover bolts first and see if the front bolt lines up. If not I will follow your fix. My front bolt is also too long and bottoms out before getting tight on the cover. Bolt was missing a washer.

I still have my tranny cover off. It was a definite source of most of my noise. Thanks! Been hunting this buzz for 3 years. It has made a big difference. From a stand still and pulling out it is quiet and very smooth sounding now. I still have some buzz on a hill under load an getting on the throttle. Have yet to ride another VALK so I don't have anything to compare to.

[Ricky-D]

I still have some buzz on a hill under load an getting on the throttle.

That could be from the drive line.

A natural occurring vibration from the increased pressures vs low rpm's.

***

[cef2lion]

I'm wondering that as well. I do know a guy that has a small bike shop near me. He happens to have an IS. Might stop by. He offered to let me drive his in the Spring. Maybe we will swap bikes and take a ride and compare notes.

[3W-lonerider]

as far as the engine noise going uphill. i think thats going to be normal because of the stress being put on the square cut tranny gears. mine has the same noise going uphill and sounds normal.

[3W-lonerider]

I still have some buzz on a hill under load an getting on the throttle.

That could be from the drive line.

A natural occurring vibration from the increased pressures vs low rpm's.

***

 while i can agree with you on the drive line giving some vibration going uphill can happen..but on this subject the driveline had absolutly nothing to do with the rattle i was experiancing. i could sit on the bike hold the rear brake and start letting the clutch out and it would start rattling. thats why i considered it to be a harmonic vibration.