So, after several tanks of testing I found out that the best way to get better performance has got more to do about the Fuel injection & ECU than the exhaust. This is a non scientific test, but after changing between the stock exhaust and the LeoVince full system a few times it became very clear. As far as ECU re setting goes, I simply disconnected the battery for 45min at each exhaust change & ground out the terminals to remove any power in the system.
First, when I put the Leo on the bike ran very lean. It had no bottom end, almost no midrange, but had better top end power due to the non restrictive exhaust. It took a couple of days, but the ECU re-mapped and the power was back, running sweet, strong bottom end & midrange, and going a lot faster, revving easier than when stock. The bike was great. Now I started playing.
I pulled the Leo off & put the stock exhaust back on. The first thing I noticed was, Wow, there is not much difference? I don’t remember the stock exhaust being this good. It had good low & midrange, but it was revving clean up to about 10,000rpm, and it’s never done that before, it always slowed down from about 8,500rpm. It was also using more fuel, but going a lot better, the reason, THE ECU had richend the fuel map when the LeoVince was installed. After a couple days it slowed up, and started to feel restricted again as the ECU leaned the bike off back into commute mode. Obviously the ECU is looking for a specific fuel/air target. By fitting the Leo the ECU has to add more fuel to achieve target, and because it is more efficient than the stock muffler I didn’t notice any big MPG changes with the leo. Based on the running I did it looks something like this. Stock bike around 77MPG, Leo around 70MPG, with the stock back on and rich ECU around 60MPG. (Now this is non scientific, just what I put back into the bike. And as it was going really good I was probably giving the throttle cable a workout too)
So my unscientific results are telling me that, as expected, Honda have the ECU set to map for economy/emission, not performance. That putting a Slip on or Full exhaust system does make a difference, but the ECU is still looking for economy, not performance. If you want performance I would start with the ECU and not the exhaust. If you want to change the look of the bike and don’t care about maximum performance just change the exhaust, it does go faster. If you want to get the best out of the bike, change both...