clunking noise under load???

[ellisjay2]

Im getting a clunking noise under a load at driving speeds that comes and goes. When it comes I ease off accelerator or ease it on down to increase speed, clunk,clunk clunk, clunk,clunk,clunk,clunking noise gets louder, faster then goes away and im able to hit high driving speeds. I think i hear it through intake manifold as if it could be valves, or something thats rotating, possible lifter or push rod maybe?? It feels as if its a misfire on a cylinder at a certain point the way it stumbles and lacks power the few seconds when it happens, Im just trying to get an idea on where to aim though I know I will be rebuilding top end from what it sounds like soon because lacking power is no way to ride. Whats the best way to chase down a misfire, go through all the wires while running and pull loose to see how engine responds?? Or does deeper inspection need to occur, im all ears........

I will video when it makes clunking noise at idle while reving sounds as if its backfiring....