My K5 750 had been running great for two years, and has run even better since I installed my Hondaman electronic ignition two months ago. This last week however, has been another story. The motor seems to have lost a lot of steam and the no. 3 header takes like 5 min to get as hot as the others. I switched the high-tension leads with no results. Battery is good, valves have set twice, compression 120-125 cold, points timing are spot on, cam tensioner set, float level checked, new plugs, carbs cleaned -synced all this week with little results. plugs look sooty save for no. 4 which is a tad lean. Jetting has been perfect for two years so I'm sure they are not to blame. I haven't checked for air leaks because there is no surging. Am I missing anything?