Same here on my 07 UC. Clatters in first gear while pulling out after things warm up. I don't notice it when it's cold.

This past weekend I installed the IDS and took it for a 2 hours 'test' ride. The clatter is gone even after a couple of hours of riding.

 

sounds like compensator bottoming out the wieghts ,at low rpm and giving it some load theres too much vibration for the weak compensator spring.if it only does it hot then i would say ignition knock.

 

My 07 started to make noise in the primary at 22K miles. The dealer put another spring or a bigger spring in the compensator and all is well at 26K now. The IDS has about 13K miles and is fine.

 

Aumotive oil in an HD, or any wet clutch motorcycle will cause clutch slippage and excess heat on the clutch.

Motorcycle oil will prevent this. I use Amsoil 20W50 motorcycle oil in all three holes and have never had a problem with clutch chatter or slippage, in the last 15 years and 8 bikes.

My .02 worth.

Steve