I bought a 1980 cb650 a few months back and have pieced this poor thing back together replacing bad with new. I now have it running, well kind of. When running the bike runs smooth except when it needs to idle, well it wont idle. It acts like it is running out of fuel. I also noticed that cylinders 3 and 4 are running much hotter than 1 and 2. I have rebuilt the carbs as per Clymers manual. It could be that 3 and 4 are running lean. All four carbs are set the same. I need to sync the carbs but need bike to idle. Any help would be greatly appreciated. Thanks.