When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I am guessing from what you are describing that what ever you are using for a cleaner is opening the pores in the paint and then a small amount of water is getting trapped in the finish when the top layer dries out.
I have found that a shot of clear paint opens the pores long enough for the water to escape and returns most of the original look.
You have to understand I am a wood repair man and this sounds just like a water mark you get on the top of a table.
It's worth a try, you only have to do a small spot at first to see if it works, sometimes you have to lay in on heavy, they do make clear engine paint. I'd try it if it has my bike before I resorted to repainting or powder coating.
I just sprayed my wife's cam cover and primary cover on her 2011 nightster. I used HD black/textured paint. Really easy to use and cheap, the paint was around $10 and one can did both parts.
Her cam cover and primary cover were stained as well, looked like ****. Looks like a million bucks now.
Harley-Davidson Fat Boy Becomes a Dark, Decepticon-Inspired Custom
Slideshow: Killer Custom's latest build relies on styling changes rather than performance upgrades, giving the cruiser an entirely different personality.
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.
Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.