Fin Corrosion; Cleaning and Prevention?

So, following some of the threads on here, and having not much to do until Spring, I decided to do a little more involved and fine cleaning/detailing. I got the plastic off my mufflers and polished some chrome, (luggage rack re-plating project in process, as I couldn't find a replacement ANYWHERE for this forgotten model?), but a week later, I suddenly have developed some corrosion on the fins, and even some of the matte black areas, after I cleaned them. I used Lemon Pledge initially on some small pipe cleaning brushes per some of the discussions I'd read on here, which seemed to work decently anyway. The next day, the results didn't seem nearly as impressive, so I sprayed on some Turtle wax Ice instant detailer that I'd purchased, then  blow dried it some with just a long wand on my air compressor, to try and give it a little more gleam. This before picture was the result, which I was fairly satisfied with. The second pic is what I discovered just a bit ago when I went in the garage to do some work on my son's car? Would the products I used cause this kind of reaction with the aluminum? They both said they were safe on all metal surfaces. My only thought was that I DO have a vat of pure bleach in the garage, (related to luggage rack project), but it's been mostly covered on the other side of the garage, and the bleach is supposed to be safe for aluminum, as it was a suggestion to strip thin chrome FROM aluminum, as it would not harm the aluminum itself, and seems to be working to some effect at least. Either way, I need to figure out how best to remove thr crud from my fins and barrels, and prevent it from recurring. Is the WD-40, (stands for water displacement formula attempt #40 from all the lore I've heard over the years), on a brush, the magic recipe as I believe John mentioned in a post long ago? Or is there something else I should try? Many thanks for any tips or suggestions...

How odd.  Almost as if the brush was contaminated with paint stripper or something!

I wonder if the lemon pledge over there is a different formulation to whatever you had read about on the forum. It’s not even available in the uk now, but it was a lemon scented furniture wax I believe.

I’ve no idea how you can remedy that sorry, Hopefully someone else will chime in .

Looks like the same stuff I got Mal, and the brushes I used were straight out of the package, but I guess it's possible they came contaminated with something? Not sure if you guys have Harbor Freight stores over there? Cheap Chinese knock-offs of about any tool you can imagine, and they just opened one 5 minutes from our house a couple years ago, so I'm in there quite frequently for this and that, and I got the whole pack of pipe brushes for $5, plus had a coopin' to get the detailing brushes free with any purchase. Ruled out the citric acid in Pledge being the cause, as I even found an article claiming that it is in fact a preventative and protector of aluminum: "The experimental results showed that citric acid inhibits the corrosion of aluminium in NaCl solution and the inhibition efficiency depends on its concentration. The protection efficiency increases with citric acid concentration"


On the other hand, I saw bleach eat a piece of aluminum foil on YouTube, so I'm guessing that just having the fumes enclosed in the garage with the bike could be the culprit. That being said; I guess the thing to do would be re-cleaning with the Pledge, and hopefully the citric acid will protect the aluminum, now that I got the bleach out of the garage, unless anyone else chimes in with a better suggestion. Will update once I know more.

Without a clear diagnosis of the cause, my solution was to wrap ArmorAll cleaning wipes around the tube brushes and re-clean everything intently, then wrapping ArmorAll protectant wipes around said brushes, and going through all the crevasses yet a third time, to try and prevent recurrence. It also meant that I had to do all the engine chrome again, as the mucking around with the other products and brushes of course smudged up and speckled the chrome anywhere I got near it, so I went over that again with the TurtleWax chrome polish. Once the sun comes out again, and I confirm that the corrosion doesn't in fact return, I will snap a couple pics in real light to show the results.

Sun finally came out today, although still not warm enough to ride, but rolled er' out in the drive to get a decent view of the barrels/fins after the Armorall cleaning and protecting...

looks good Barry!

Good as new again!

 Bikes looking very tidy Barry 

Yeah Sim; can't wait to get it out to get dirty in the elements again!