Take it for a 10 - 15 minute ride.  Using something with an edge but not too sharp (don't want to scratch) metal would be OK but some other type of material that won't melt would be better, I used a couple of Popsicle sticks, scrape the hopefully now soft goo off the best you can trying to not cut into the stainless, just softly scraping the surface.  After the pipe cools completely use some kind of soft rag and metal polish to clean the remaining material off.
I use this stuff, don't know if you have anything similar in OZ or not.  It is wadding that is impregnated with a polish compound.  You tear off a piece and start polishing.
I did this process on one of the StainTune pipes on my Ducati when my wife touched the hot pipe with her tennis shoe.
HTH and good luck.
Gerry

I always use #0000 steel wool, get it at a hardware store, great for polishing good chrome... don't put too much hand pressure on it though.
But you will have to heat it up first and scrape off what you can, you can use the steel wool to kind of "mop" it off the pipe while hot, but I would wear some really good heat resistant glove.

Thanks guys