Picking Brains

Hello all again, My Bonneville wants for nothing so she's all covered up. I need to pick the brains of properly some of the older members of the community, who I have noticed build other bikes beside triumphs and are used to those older big single thumpers.
Unfortunately I have bought a 2006 Royal Enfield Bullit 500cc single simply because it was cheap.
I have managed to get it running, it mis fires a bit when the throttle is opened but this is improving the more I run it properly wants good blast down the road, I don't know.
Main problem I don't know anything about is that when I put on the front brake, push hard down on the forks, and as the forks return up there seems to be a knocking noise just as thy reach the top of there travel, This bike has been standing in a greenhouse for about 3years, but not sure that's relevant.
Any suggestions please. Even what a knob for buying it.
Thank you
mallywoods (again)

 

Wouldn't I be able to feel/see any play by having the front wheel of the floor, and pulling the forks back and forth.

 

Thanks for reply, I will check it out.

 

That's good news for me, Thank you.

 

I know it's now running, I think it will get a mot know I know about that bit of knocking on the forks rebound, then believe me I will no longer have a 2006 Royal Enfield. Your right.

 

That's the best offer I've had so far.