Well my barn find 87 is just about ready to roll. I rebuilt the carbs, lubed the splines put oversize metzlers on it put a new fuel tank on, found a new factory fairing for it, installed a datel meter on the fairing with a direct feed relayed through to the battery, replaced the r/r, installed new fork seals,replaced the plugs, rebuilt the petcock,replaced the bullet connectors in the bucket with weatherpack connectors,replaced the crush gaskets, removed the fresh air solenoid and hoses, installed k&n filters, put new throttle and choke cables on, replaced the speedo cable, fixed the ignition switch , installed a luggage rack and a few other things. I just synced the carbs and notice at a cold start up the rear exhaust stays cold when the front heats up.The spark checks out OK. When the engine warms up and I rev it the rear exhaust warms up fast. The thing is I can not detect any miss at any time. I test drove it for ten miles and she goes good, no missing, no backfires. The cold exhaust stumps me though. What do you guys think?