A Worrying Noise

[Lucky_Lou]

After a short ride over to my brothers this morning i got this "ringing' noise when i got home at first i thought it was coming from the front of the engine but when i got my head down it seems to be in the middle any ideas?
http://www.youtube.com/watch?v=rURYWbdAjhw
Ta Lou

[Adamastor]

Wow... that's definitively a strange sound.. the chain and chain tensioner in good shape? Checked if anything is loose at the exhaust supports?

[Mike V]

Lou,

Very strange. Pidgeons? Shooting at windmills here but have you checked the crankcase breather valve? Anything stashed in the backbone tube? Tank connection points? I got nothing else. Is there any change in performance?

Sure is a pretty bike.

[Lucky_Lou]

I let it cool down for a few hours then started it up...no noise??? rode up to Squires to chew the fat with the guys (20 odd miles) no noise?? weird will have to let this one develop but it definitely sounded like it was coming from the crankcase.
Lou
ps thanks MikeV ive told Gertie she has a fan.

[Semper Gumby]

I've had some weird things make noise.  I would make sure the front cover and the starter cover are snug.  Then I would check both motor mounts.  Then I would check the tranny to engine bolts  (there are four with two inside the airbox.)  While you're there I would make sure the airbox is snug and I would also pull the breather cover and look for something stupid.  That sounds like gurgling.

But before you do any of this -- e-amil this video link to Oak Oakenshield at www.airheads.org.
 
I bet HE has heard this noise before.

(I wonder if it could be piston slap or small end bushings.  If it goes away at speed but comes back at idle it might be the small end bearings.  The timing chain valve noises all sound just like my bike -- BMW sewing machine!!!!)

Does sort of sound like the tank.  Does it make the same sound with a full tank as an empty one.  Sounds like an empty tank bumping against something.

Good luck Lou.   :-/

[bubby-joe]

What a racket.  I'd check both ends. the flywheel and clutch assembly take it apart check everything, as well as the alternator bolt and stator housing, had a marine engine sound similar and the drive coupling had 1 broken bolt and  3 loose ones, pulled the engine while being towed in, 4X4 and a come along wound up replacing the coupling, and the bolts and then re-torque everything and the noise was gone.  Don't wait if it breaks at either end it gets very messy to fix....failure is not an option.

[Barry]

Can't add anything to what's been said about the noise Lou.

I did learn something from your video though.  I thought all flat top bings would be the same but it seems there are different models as mine have a plain flat top where yours look to have a shallow depression.

[Lucky_Lou]

But before you do any of this -- e-amil this video link to Oak Oakenshield at www.airheads.org.
 
I bet HE has heard this noise before.  :-/

Ive forwarded the link to AskOak@aol.com hope thats the right email as im not a member of the Airheads.The tank was full when this happend.I wonder if its related to the screech i had a couple of month back that disappeared too.  
The carbs do have a slight depression Barry, ive not seen any other flat tops to compare them too though.
Lou

[Bob_Roller]

I've seen a couple of videos with bikes that were making an unusual noise, from what I can tell from your video clip, I'd check out the crankcase breather valve, sounds quite similar to what I've heard before .

It was the breather valve in those cases .

Don't know what goes wrong with them, but they are a spring loaded valve .

[Lucky_Lou]

Here,s Oaks response....
Mike:

There are several possibilities. The 1979 models use points inside the
timing canister frequently called the " bean can " When the rubbing block goes
dry it can create a harmless horribly loud noise at lower engine speeds.

Open the front of the canister ( 2 screws) and carefully remove the cover.
Where the points rubbing block rubs the steel cam, apply a tiny amount of
rubbing block high temperature grease. Careful not to get any on the points.
See if that clears up the noise.

Let me know what you find out.........Oak

I will do this before the weekend and let you know the result.
Mike aka Lucky Lou

[Semper Gumby]

Oak is one of treasures of the airhead community.

[Lucky_Lou]

Oak is one of treasures of the airhead community.

Hes definitely on my Christmas card list...
Lou

[ambrose78]

Very strange. Pidgeons?  

x2 with the pidgeons.. LOL

Other that that noise she seems to be making pretty healthy BMW sounds..