I recently got a 1986 sprotster 1100 running again. I replaced the plugs and rebuilt the carb. When I put some new gas in it, it started as soon as I hit the switch. But when it started, IT REAAAALLLLYYYY STARTED!!! It actually scared me a bit and I had to jump and turn it off. The throttle was completely off. The throttle screw was backed all the way out and the choke was 3/4 of the way out. I decided to screw the idle mixture screw down tighter and that didnt help. So I backed it out and it helped a little. Then I messed with the choke and I found a happy medium at the HALF WAY MARK. (which is really weird, never seen a carb do that) If I drop the choke all the way down (where a normal idle would be), the engine screams. If the choke is all the way up (where a realativley high idle would be) the engine screams. When the choke is at the middle, the idle is lower but it is not a steady idle. There is no harley put put... put put... put put..., it is an unsteady idle. Does anyone know what I did wrong on my carb rebuild??????