Had a little experiment! With a bit of time to kill I took my flapper valve out, left the cross shaft with cable and servo still operating just undid the screws holding the flap on . It's made a big difference especially at 3-4k rpms when around town or in traffic as it's stopped the annoying surging. In all the bike feels smoother and slightly less hesitant at low and mid range
Drill the flapper valve out all together....i did a detailed walk through on it....its here somewhere....
I removed the flap and left everything else in place.makes the bike a lot nicer to ride around town and in traffic. I am lead to believe its only purpose is to get the bike through noise emissions . This makes sense as the bike sounds a little better.
Yeah that's what I did as I've read removing cables throws up error codes as the servo needs to hit end stops on start up
Yarp - you need to get it to a good dyno operator....if he knows his stuff the flapper valve motor can be deleted within the ecu settings - you can pull the whole lot out then!
Not sure where you are in the world but if your near Bristol book your bike in with CJS racing....If youre serious about keeping your bike long term, get a full system on it, also, change the air filer for a K&N or the like, better still a velocity kit (not sure if they do them for an 821 though) get it to Chris and I absolutely guarantee youll be hanging on to it after he's done his stuff....it will be a night and day change to the way it goes.
Not sure....it is only for noise...and, if you bought a full system there wouldnt be a need for the valve motor anyway...(posting this from the top of a shipping container at gorse lea , McGuiness just went past...)
