This is my story and I am sticking to it:
Using a wet lubricant on a chain produces the stuff below in no time, as dust is picked up from the wheels, the road and everything that resides on the pavement we ride on.
This pic below is made from exactly the same stuff, lubricant and carborundum (fine soil particles)
View attachment 1586547
I use to be a faithful DuPont dry lube user, until experience taught me a lesson when it comes to chains. It kept my chain shiny and clean, happy customer, but then I found this out....
I am a competitive cyclist, been for years, still race Masters. Our bikes use an 11 speed chain and cassette, no O-Rings. The chains last around 3,000 miles and cost around $45. The cassettes last around 20,000 miles provided they never see a stretched chain, they go for around $450. Due to the expense of damaging the cassette, we measure our chains for stretch often and replace them when they get close to max stretch allowance.
I started using DuPont on these chains as soon as the original factory lube wore out. The chains developed a squeak after applying DuPont within 200 miles. The chain life reduced to below 2,000 miles. We train around 1,000 miles a month, so we change chains every 2-3 months, more than anyone will normally do on a Busa.
The only way to take care of a chain properly, is to remove it from the bike, wash it thoroughly in an ultrasonic submersible cleaner, then get lube into the pins and bushings and dry the externals as much as possible. This is not possible on an o-ring motorcycle chain.
For what it is worth, my Busa only has 11,000 miles since I purchased it new in 2009. My chain was cleaned at around 600 miles and never lubed again. It is still on the factory adjustment setting and the slack is still OK.