My story is a common one: The original exhaust system rusted out rather badly at its lowest point within 5-6 years of the bike being new. At that time I put on an aftermarket 6-into-2 that I believe was made by Kerker. However although louder, the CBX didn't make as much low-end torque where I used it the most. After living with the Kerkers for awhile I knew that someday I would want to return to stock exhausts and so bit the bullet and ordered a pair from Honda. They took 3 months to arrive for the outrageous cost of around $700 for the pair.
At that point they went into dry protected storage.Fast forward several more years and I am ready to install them. That's when I finally noticed that there were NO DRAIN HOLES at the low points. Every Honda Four I had ever owned had these holes from the factory to allow moisture to drain from the pipes. No wonder the CBX pipes rusted so quickly! So before installation, I drilled a single 1/8" hole in each pipe at the low point and sprayed aluminum rust preventative paint through the holes. From that point on, following every ride I have religiously sprayed WD-40 or a similar rust preventing lubricant through these new holes and also sprayed it into the holes under the muffler outlets until it drips out of the bottom holes.
Although there is sometimes a little smoke as this oil burns off at the beginning of each new ride, it has kept the new exhausts structurally sound for 10 years.
FWIW, Milt
and rubber band some baggies over the ends when washing. Thought about slugging them full of silver Rustoleum and hanging them up and let it drip out, heard somewhere this was an old beemer trick.