I took a bit of a different approach to the modifications on my R, having read everything I can find regarding aftermarket items it just doe's not seem like you get a realy big bang for the buck's spent.
Air Box- I took a big paper clip and attached the flapper door in the open position, still not happy with the size of the intake I decided to look for options to get it more air. I ended up using 3, 1" soffett vents in the air box door, 1" wood bit worked great. The ones I have drain back to the outside should they get water in them. Easy to tape over if wet conditions dictate. I want to get an aftermarket filter soon.
PIPE- wanting to see if I could improve the flow a bit as well as keeping the quiet close to stock as possible. I ride where spark arrestors are mandatory so an aftermarket tip would not work. I ended up taking the end cap and spark arrestor off an drilling 2-3/8 holes in the center down in the muffler. Spark arrester and cap back on, in business.
Started it up and it sounded a bit stronger, rode around the block and is seemed to pull better. Went on 130 mile ride yesterday and I felt I was coming off the corners much harder.
I was pretty careful to do mod's that could be put back to stock very easily as well as staying withing the adjustability of the stock ECU.
My biggest expense was $16.95 for the 24" 3/8 bit
Swarty