Hey guys new to here and yamaha sled world. I was hoping i could get some advise on a issue im having with my 85 ss440. It will start up and run like hell then when you hit around 35-40 it falls on its face. Im thinking its eother a float adjustment or a fuel pump issue cuz if you give it a little time at light throttle it will take off. Also the keihin carb has a mixture screw on top that doesnt change anything at all when i move it, any ideas what could cause that. I love this sled but i hate that carb is there a good swap for them? maybe dual carb. Thanks in advance everyone.