There's a lot going on in that big goofy goiter hanging off the side of the VFR. To meet noise emissions testing a bike like this needs a quiet muffler. A quiet muffler is a restrictive muffler and a a restrictive muffler restricts performance. So they defeat the noise testing by fitting a muffler that is quiet within the testing range only (usually up to 50% of max RPM... 5000rpm in this case) The way they do this on the VFR is by using dual exhaust outlets. There is the small outlet on the bottom, no more than 2cm in diameter that exhaust gasses flow through below 5500RPM. Then there is a larger upper outlet that allows more exhaust volume to flow above 5500RPM. The flow is controlled by a "flapper" valve that is opened up using an electric servo motor, allowing exhaust to move through the larger outlet. Honda designed a sort of "failsafe" on the VFR1200 where they reversed the manner of operation. The default position of the exhaust flapper is the "open" position, and the servo motor actually holds it shut in the noise testing range. Due to this design, you can disable the system and the flapper will stay in the open position. The flapper is located in the end of the muffler, and the servo motor is located under the seat. They are connected by a cable. The easiest way to disable the system is to simply disconnect the cable. I went one better and removed the cable altogether. If would be nice to bin the servo motor as well, but it has a built-in feedback system to assure the ECU that the valve is in the correct position... if you remove the servo motor, you trip a fault code in the fuel injection and the bike goes into a "limp-home" mode with a flashing engine light.
Here's how it went:
Seat comes off:
Another example of quality... little rubber washers for the bolts that hold the cowl down
This is the flapper in the closed position:
Remove the cable from the bell crank.
The muffler swings away so the wheel can be removed. I took the cable out.
I started the bike and it definitely sounds better. More throaty and deep sounding. I'm looking forward to taking it for a ride and seeing if this helps improve the low-end torque.