I have a loud whirring sound coming from the primary on my 2005 heritage sottail

SOURCE: STAARTED BIKE AND PUT IN GEAR. HEARD A LOUD CLUNK

That's really a good sign. It tells me that it's probably not something inside the transmission. I'd be willing to bet that it's the front belt pulley. The splines have probably worn out and the final drive gear is turning inside the pulley. I've seen this a time or two and not just on Harley's. Remember the Excelsior-Hendersons that were reintroduced in the late '90's? They had a real bad problem with that and were all recalled to replace the pulleys.

The pulley's are made intentionally soft so that the pulley wears, not the final drive gear in the transmission. The pulley is much less expensive than the gear and only a third of the labor to change it out.

This would be my "best guess". Of course, since I'm not there to look at the bike or anything, a "guess" is the best I can do. But if your transmission is shifting and not making any noises with the engine running, you bike just won't move, I'd say the front pulley is like the problem. Let's hope I'm correct.

Good Luck
steve

Testimonial: "your feedback was right no the money. although the belt was broke and the pully is still ok, I think Ill replace the pully too after your comments."

SOURCE: I'm looking at a post by a guy: By traque59 on Jul

did this all happen suddenly or gradualy

SOURCE: Hi I have a harley

Possibly a clutch or primary chain problem or more than likely the layshaft in the gearbox is not driving the mainshaft due to a pawl missing on the selector. The main drive belt is OK I suppose?
Strip down the gear box to find out.

SOURCE: hello I own a 05 1200c sportster. I was about to

The first and easiest thing to check is the primary chain tension. In the middle of the top run, you should have 3/8" to 1/2" up and down play with the engine cold. Check this through the small hole in the top of the outer primary cover. Adjust with the adjuster screw on the underside of the cover. Also look on the inside of the outer cover to see if the sprocket shaft nut has come loose and is rubbing the cover. It could also be a magnet in the rotor on your alternator has come loose. To check that, you'll have to pull the primary chain, engine sprocket, and clutch assembly off to get the rotor off. The mainshaft nut that holds the clutch on had left handed threads.

Good Lucki
Steve