Speedometer noise?

[Rikugun]

I went for a ride which lasted 110 miles on Sunday. There were several stops but on the last 10 miles or so I noticed a strange noise. I could only hear it approaching a stop where wind noise was sufficiently diminished and with ear plugs and a full face helmet it was still subtle. Just before coming to a complete stop it would disappear.

It seemed to be road speed dependent rather than RPM. First I thought it had something to do with my recently added rotor/caliper combo but the next stop was rear brake only and the noise was still there. I've never experienced it first hand but the speedometer bushing came to mind. I've read of this particular problem but don't recall how the noise was described. I'm not sure I can describe it accurately myself having only heard it a few times prior to getting home. If I gave it human characteristics I'd say something like a whine or moan or groan. Clearly something was unhappy!

Yesterday I tried to duplicate the noise by spinning up the speedo with a drill driver attached to the cable at the wheel end but no noise. Is the dry bushing  syndrome initially intermittent or take some miles to develop? It may be the noise wasn't coming from the front either so any other suggestions would be welcome.

[jefferson]

I would start with the cable first and make sure it is lubed up good. If that doesn't take care of it then yes I would bet on the bushing.

[QBS]

I would put the order of guilt first on the bushing and lube it as I have suggested several times before.  If that fails to give relief, lube the cable.  When the bushing lubrication begins to fail the noise is often intermittent and inconsistent in tone.  Feel the speedo housing while the noise is evident.  Look for vibration.  Hold your hand on the speedo housing as the bike comes to a halt.  See if the housing vibration (beside engine vibration) stops with the end of wheel rotation.  If so, then you have confirmed that your bushing needs lubrication.  In cases of advanced failure the degree of vibration is truly amazing and has to be felt to be believed. 

As the lube failure progresses, the noise will become louder, higher in pitch, less intermittent, and the vibration will get worse.

[The Prophet of Doom]

I had a terrible whine on my bike years ago which became louder, higher in pitch, less intermittent with every kilometer.  Clearly something was unhappy!
After I dropped my girlfriend off it went away.   ;D

[Rikugun]

That's funny - kinda reminds me of a Rodney Dangerfield setup.  :)

Jefferson, I appreciate the "check the simple things first" technique. The cables get lubed as part of my maintenance regime so sadly that wasn't it.

QBS, thanks for the insight. I appreciate the detail regarding the progression of symptoms. That makes me fairly confident a dry bushing is the culprit. I was going to investigate the temp gage and sensor accuracy so now I have a two reasons to get started looking into the instrument cluster.

[skucera]

Last summer I had a noisy speedo bushing too.  A little gun oil made it quiet again, but it did require taking the instrument nacelle apart to do it.  It wasn't rocket science.

Scott