My daily ride needed to be unleashed and the V4 allowed to breathe. I acquired the twin Leo Vince slip on cans that took about 20 minutes to install while fighting around the license plate holder which we were too lazy to remove (the stock exhaust was quickly off with just a couple of bolts which made things a lot easier). As always, a lot of time was spent aligning the stainless steel cans perfectly (I’m very detail oriented).

I have to say that the sound is very similar to my R1 at low rpm’s, but when the revs pick up the RSV4 “sound” comes in to distinguish the V4’s unique howl.

To improve the fuel map and engine performance in general We installed a Power Commander 5. A very simple operation that literally to less than 10 minutes and required the removal of the seat and access to the right side of the bike and 2 fairing bolts removed to plug the PC5 in to the harness. In preparation for the dyno run we pinched off the air injection system (has to be done to get a good map setting) and then attached an O2 sensor from the dyno to the header to allow accurate sampling. To do those tasks we removed the left side lower fairing which too a little more than 3 minutes.

After 30 minutes of work on the dyno with roll on and partial throttle openings reviewed and altered, a very different fuel and power map emerged as an end result. Where the bike had been very weak and wheezy after 5-6,000rpm it now pulled cleanly from middle of the range all the way past 11,000rpm. Not bad for an 02 with 24,000 miles on it and a credit to the PC5 which took such little work to dial in.


For me, knowing I have more mid range and a smoother roll on with even power gains makes me know the bike can do things in traffic that it could not do before, and that could save my life. Add to that the delicious sound of the exhaust note and a visceral experience is on tap as soon as the bike is fired up!

– The final power and fuel map in the bike and readings it gave

FOOT NOTE: I’ve put almost 1,000 miles on the bike now and I really do notice the gains in the middle of the rev range which has made the bike much more pleasurable to ride indeed without losing much in the way of fuel economy unless I open the V-Tech up and then of course, mileage plummets……. The pipes are not loud at all, but they attract all kinds of attention when I pull up somewhere with people wanting to know what engine is inside those fairings! I tell them to buy a VFR800, get the Leo Vince slip on cans and then add the PC5 to the equation for hours of symphonic sounds from the exhaust.