Why did my pipe discolor so quickly?

Too much oil actually leans out the gas/air ratio! Use 24:1

One of the most common problems involving motorcycle parts is that which involve exhaust systems. These problems may include cosmetic problems like bluing and other related discrepancies.
If you are already in possession of your desired motorcycle exhaust, be sure to coat it with Blue-Shield, Dyno Kote or other compatible products in order to preclude the exhaust from turning blue.
If your exhaust system has transformed from chrome to bluish black, use blue-away, blue-buster and other suitable product depending on your bike’s brand. Apply it with a little elbow grease to achieve best results.

In case your pipes become blue too quickly or over and over again, it can be a manifestation that the air-fuel mixture or timing is not right or accurate. To overdo the mixture and make it overly rich can turn the pipe or muffler blue. This is because the unburned gas ignites on a baffle or hot spot. Too lean mixture or timing can cause pinging. It can also turn an extremely hot exhaust into blue.

if this was any other exhaust, i'd agree with Gene, above. but with these, it discolors because "you get what you pay for."

i don't think cleaning it or treating it with any product will help. these exhausts run too hot, are poorly built, and it is what it is.

i use a chemical paint stripper on the black exhausts before i even mount them. get it down to steel, and watch it turn blue-black.

my first black exhaust burnt off half the paint the first day. it was the only time my bike ever smoked, and i thought it was on fire for a second, because of the smell.

plus, the painted ones use about 37 coats of thick black paint (give or take 13 coats,) and it's a real pain to get it all off.

it's just one of those things we have to put up with when riding these bikes.