Hi guys, not sure if anyone would be still watching this thread but will give it a go anyway, had a worrying knock in the front of my 2011 fatbob and while reaserching the internet I came across this thread.
So after much investigation I had come to the conclusion the knock was in the forks, this morning I pulled the forks apart and replaced the oil. To my suprise the Climber manual that I purchased showed specs that looked nothing like the insides of my fork assembly, and where the manual advised 325ml of oil, I poured 725ml of oil out of the fork, so over to the nearest bike shop to have a quick talk to the local mechanic about this strange scenario I found myself in, the helpful, friendly mechanic advised that my forks had been modified with a shorter progressive spring and a half foot long spacer, "just make sure you leave 130mm air space" the mechanic advised.
Put it all back together and out for the test ride, knock still there. While leaning over the bike to listen to this incessant knock I was holding the tank and was sure I felt it move, when I pulled up I grabbed the front of the tank and gave a solid pull and, KNOCK there it was, after all that work it ended up being a loose front fuel tank bolt.
Anyway that's my story just incase anyone is still listening. Ride safe everyone.