I have an 05 nightrain efi. My ecm just took a crap and was looking at the thundermax open loop system. The only mods on the bike are Se air cleaner and V&H straight shots. Other than that, it's stock. A blank ecm is $340 plus the download and any labor, so I figure about another $200 out the door. The thundermax ecm is $485 and it's capable to go to a closed loop system in the future. Plus I don't have to get the bike to a dealer to do the repair. My bike being almost stock, they would have a map pretty close to the harley stageI download from Harley. I was planning some upgrades in the future, so I was leaning toward the Thumdermax system. Any thoughts or experiences? Thanks

 

I put the T-Max on my 03, however welded bungs on the pipes for O2 sensors for the autotune. I made a couple of timing and A/F changes and she runs like a scared rabbit. My fuel mileage is around 38mpg. I'm quite happy with it and do recommend it, but unfortunately can't tell you about open loop.