From what I know it is a stock bike with a Yoshimura pipe. I have installed Ecliptech dual light driver kit to run 55w headlights safely, and also an Ecliptech LED tail light kit for that modern, bright look.
Bike goes well, sounds tough and I enjoy riding it. Currently been in my hands for about 2 months. Has about 28k kms on the clock, which no doubt is bogus.
It is my second bike, my first being a Ninja 300. I love the handling of the RVF400, which I experienced doing a natio run.
Looking forward to riding it on my Ls and Ps (soonish ).