Hi all. I have an 82, 15 HP. that I need advice on. If I let go of the throttle arm the motor speed slows to a very slow speed. I would like to adjust the tiller arm a little so that it stays where I set it but I can't find any reference to the adjustment in my manual. There is a part under the handle called a friction ring but there is no adjustment on it. Can anyone help? Thanks, Rick.