I'm hunting for the cause of my surging bike, and I've had carbs & fuel suggested to me a few times. I checked out what my dealer service manual had to say, (nice 4 port digital tool incidently) and got myself a vacuum gauge.
My problem is, at idle, the vacuum is completely unreadable because it oscillates around so much. At 2000 rpm it begins to firm up and 2500 - 3000 it is pretty rock steady.
Does this indicate I have a vacuum leak? Could this be indicative of fuel supply issues? I tested 1st and 4th and got the same behaviour and then called a halt since I didn't know how to interpret the data.
Is this normal behaviour? thanks for any insight