Quick question...can a bad O2 sensor cause a hard cold start?

 

The O2 sensor doesn't function until after the bike is running, so that in and of itself isn't going to cause that problem.
It's possible a bad O2 sensor has given you a rich condition which could foul your plugs, giving you a hard start condition. Start pulling some codes to see what it shows.

 

Yes the fuel management system does not use O2 sensors until the engine reaches a set operating temp, it just runs off of a fuel enrichment map. Once temp is reached the system goes into a closed loop mode with sensor feedback. As stated, maybe a bad or weak spark?

 

Quick question...can a bad O2 sensor cause a hard cold start?

No.... First check would be the engine temperature sensor. I'm assuming it's a thermistor with an ohm range based upon temp. Knowing Harley, it could be a switch type sensor though. I'm sure someone here knows. This could be the cause because if it is stuck in one position, the PCM would think that the engine is fully warmed up when you try to start cold and not give any cold start enrichment.

 

I'd try a new set of plugs first.

 

I turned the ACR off by mistake with the super tuner. It caused my 13 limited to have hard start problems.