idle issue

[revhead]

but once revved the bike will hang at about 1700rpm,

id be spraying a little mist of water using a little spray bottle ,across the inlet tubes while it is running to see if you have an air leak,it will splutter, there is one little bastard of an air line that has a T piece init this sits between the bottom of #2 an#3 throttle body,also check the little rubber blank offs on 2,3,4 throttle bodies as they perish,