I have 2009 Ultra that is bone stock just like the day I picked it up from the dealer. While on a 1200 mi trip to the mountains this past weekend, everyone that was behind me on downhill hard deceleration (3000+ rpm w/o any throttle input) stated my bike was smoking out of the left pipe and the left pipe only.

It did this consistanly and a repeatedly on hard decel over a period of 3-4 days. The smoke was described as blueish, not black or grey, so I'm thinking oil smoke. Why would hard decels cause this smoking condition if I had a problem like bad cylinder ring or valve seal issue? Why would it not just smoke all the time? The bike runs great and I didn't see any measureable diff in the oil levels over the weekend but I didn't check the oil before I left or after I got home so really don't know what the level was to start with...

The spark plugs look great. Both cylinders are burning greyish/white. Bike now has 2700 miles...

 

Two Words: Warranty/ Dealership.

 

I would say something is not right, maybe be big, may be small, but something is wrong. JMO. I never want to see any sort of smoke coming out of my pipes. Of course, I don't really know ****, but I'd hit the dealer ASAP.

 

What they said.

 

+1 - dealer/warranty

Since this only happens on hard deceleration, I wonder if it has something to do with increased engine vacuum?

 

I believe it's the way HD has designed their breather system. Your oil vapor is being pulled thru the hoses in the AC more than normal. If I decelerate hard I keep my throttle cracked just a tad and that seems to eliminate most of it. I bet your AC was full of oil too.

 

This confuses me!

 

Me, well I'm wondering IF there was too much oil in the crankcase to begin with. Like my youngest kid says... "Just wondering..."

 

I smoke on my ultra all the time, gotta love that cig. lighter.

 

I'd suspect the valve seals - snapping the throttle shut could result in oil being pulled down through the guides.