I have a 1995 Sportster XLH 1200. It has developed a "whirring" noise while riding, usually can hear it above 10 MPH but will slow down and "drop off" around 10 MPH right before stopping. This noise will not be present all the time, but have noticed it will usually appear while shifting into 3rd gear...Any ideas? I have also gone as far as shifting to neutral...shutting the bike off and just rolling. NOISE is still there...clutch pulled in or out...

 

first thought that popped into my head was tight primary chain.

 

Chain in adjusted correctly...this noise always starts when changing to 3rd gear. No clutch slippage...

 

Rough bearing? Lots of them in there.

 

ya.. sounds like your primary chain is too tight.

 

Primary chain is adjusted correctly. This noise is not present all the time...

 

How many miles on the bike?
Ever replaced the primary chain adjuster shoe?

 

Has right at 14,000 miles.....Have not been into the case yet.

 

try new gear oil/lube check and make sure there is enough in it
the 3rd gears might be tighter tolerances than the rest of the gears since highway,and in town limit use to 1st 2nd and 5th? i am guessing
new gears will whine, like a gear drive on car motors, oil will quieten it , hope this is the case