I know these sportsters are noisy engines, but notice a new sound like a rattle if I am maybe one gear high and I give it a fair amount of throttle, now I am not lugging the bike I know they don't like that but if I am coming up to a red stop light and I am letting off the throttle and then it turns green a and I start to accelerate with out down shifting any ideas, this is a new noise and the bike is an 05 1200R with 7k miles thanks

 

I would check the adjustment on the primary first.

 

mobil 1 - you will thank me

 

From how you described it, it sounds like clutch rattle. Basically it's when you have too much torq being applied on the clutch, and the clutch is slipping which results in either a moaning sound, and sometimes more of a rattle clatter type sound. The rattle actually comes from the tranny, when the clutch slips quickly your transmission gear dogs slam forward and backward on the gear that their engaged in. So obviously it's not good for your tranny, so try to avoid doing it!!! Either drop gear down where it should be, or atleast really feather the clutch release while getting your speed up for the gear selected. Also like molsenice said, try mobil 1 v-twin 20w-50 v-twin oil, it'll help with smoother clutch action, really reducing clutch moaning, and helping with overall operation.

 

i am using mobile 1 vtwin, it does not feel\sound like clutch chatter i am not lugging it and i do feather the clutch when needed (i have many years of offroad experience), thanks for all the input guys