Re: Idle speed for 50’s OMC’s ? Home › Forum › Ask A Member › Idle speed for 50’s OMC’s ? › Re: Idle speed for 50’s OMC’s ? frankrUS Member - 1 Year (includes $3 online payment fee)Replies: 6715Topics: 51 June 15, 2018 at 8:30 pm #77998 I love it when they’ll get down around 500 rpm. Not many can do that. An old Scott or Champion single can do it with ease.