thanks for the feedback. I was concerned about the precheck when the bike checks the valve unit and noticing it not there. I found this video on youtube ,For bikes built before model year 2017 you won't get an error on the dash. There is a "silent" error when you hook up a GS-911 diagnostics gadget or the bike dealer connects to your bike, but it doesn't affect the running of he bike. I have a 2014 bike and it's run completely fine for the best part of 5 years without the flapper valve.