I have a 2008 fxdf. The compressor is rated at max 15 amp . Seems to me the bike puts out 30 amps. will this work? Should i use the sae connector or do I have to hook directly to the battery posts?

 

The common SAE 2 pin flat connector, commonly used on trickle chargers, is OK at 15 amps. The compressor probably only draws that much briefly. The normal operating current is probably far less.

Connector or not, I would run the compressor power leads from the battery thru a relay. The relay will allow a much smaller switch to be employed for control.