No broken cam tensioner and nothing wrong in the valve train,
They cranked it up last Saturday before they closed and it was running on one cylinder. They tore into it Wednesday. Pulled the plugs, compression good on both cylinders. Opened the cam cavity, tensioner and everything looked fine. Looked at primary drive chain, tension was correct. Queried ECM...no fault codes. Ran without the Dyno Jet, no problems. They did notice that the plug gaps were too tight. I installed them two weeks ago and gapped them per the direction on the back of the SE box they came in...035 for that part #32192-10. The service manager said they should be at .040. I looked at the box later that night, there are three plug part number where it calls out a .040 gap (32187-10, 32188-10, 32189-10.) The part number I purchased clearly calls out .035. I told them to hold on to them. Having a hard time accepting that plugs brought all this on. Also heard HD motors can sometimes start up and run backwards and sound like it's about to come apart. Maybe I had that going on. Has anyone heard of this before? If so what causes it? And if this did happen wouldn't a fault be declared (crank sensor sensing the crank is spinning in the wrong direction?)
They've put 50 miles on the bike with no problems. I won't be able to pick it up till next Friday. I told them to crank it up and run it each day. He said the noise I heard was spark knock on one of the cylinders. I told him I've heard plenty of that before on small block chevys but nothing that violent. I talked to a friend who's owned multiple Harley's and said a spark knock on a HD V twin can sound awful. With no water jacket surrounding the cylinders to muffle the sound, it sounds like the bike is about to come apart.
I'd certainly like to hear what everyone has to say. Maybe I just had one plug go out and the noise I heard was typical for a V twin running on one cylinder. That's why I didn't hear the noise on the 3rd attempt becuse the bike only turned over but would not start.