jonmrock

got an 86 radian yx600 -- 599cc. it's a blast, not the biggest of bikes but it gets the job done. i took it to tennesee from chicago and it did surprisingly well. that being said i think next time ill take the backroads. its not a great highway bike.

I also have an 86 Radian with 15,000 miles. I am also having the same knocking sound problem EXACTLY as you described, when its cold, and under 1300 rpm. I'm going to take it in and have the valves looked at as well as havee the carbs synced. ill let you know what happends.