My mate Bob suggested I get the Booster Plug for my bike to help smooth out the touchy throttle of the Kawasaki Vulcan S. The modified exhaust has already made a big difference there, but I’m getting a lot of popping under engine breaking conditions and the Booster Plug is supposed to help that situation so I ordered one. It was a relatively easy installation and I found a couple of related videos on how to replace the air filter, which is in the same location. Anyway, if you want to find out more about the Booster Plug, which suits nearly all bikes produced after 2008 then check out the link below.
The BoosterPlug
https://www.boosterplug.com/shop/frontpage.html
The service manual said that the ECU will remap automatically once I ride the bike for 3 riding sessions of 20 minutes each. That was completed today (29th June) and the engine light has now gone out which means the ECU has re-calibrated.