I have a 2004 FLSTFI (Fatboy) fuel injected and the previous owner had put a Screamin Eagle Air cleaner and Vance and Hines Staggered big shot pipes on it but I don’t see or think he ever bought a tuner. I don’t see one anywhere on the bike. My question is with these modifications do I need a tuner and if so which one should I buy?

 

It's entirely possible the bike was tuned... not all tuners, IMHO the best ones, don't stay connected to the motorcycle. They just flash a new tune in the ECM.

During those years, Harley offered a tune cartridge that would flash the ECM with the proper tune through the data port.... then it was disconnected. A dealer could also flash a tune with their Digital Tech computer. Now there are several aftermarket tuners that can flash a tune into your ECM.

The best way to check if it was tuned, is to borrow a tuner from a friend, and get the ECM info. It's called "Vehicle Info" on the PowerVision tuner. Most tuners will read the ECM and trouble codes without being married to the ECM. The "Vehicle Info" will show what tune is in the ECM.

This is from my friend's bike. I got the info with my PowerVision tuner (not married to his bike):



This screen shows the Calibration Identification, "ECU CalID: 32725-04A". That calibration part number is the HD "1450 Stage I Legal" tune, flashed to the ECM by a dealer's Digital Tech computer. If it were flashed by the HD Stage I tune cartridge, it would be calibration ID "32957-04A" for the same tune.

If you have either of those tunes in your ECM, you are good to go....

If it were a non-HD tune in the ECM, the Calibration ID would not be an HD part number. It would be identified by whatever code the tuner uses for his tunes. That would also show the bike was tuned.

Specific to your bike, with the mods you listed, if you are not getting a lot of decel popping, I would suspect your bike has been tuned. That exhaust tends to pop a bit.

I have the V&H Big Shot exhaust on my 2003 EFI w/ 95" Big Bore kit. Even with the appropriate HD Stage II tune, it popped a bit on decel. I had DynoJet "tweak" the tune, I flashed that tune into my ECM, and now it's perfect... no decel popping at all. That was a Stage II, I believe the Stage I tunes don't pop as much with that exhaust, but I'm not positive about that.

I hope this info helps....

 

I did purchase the bike from a Harley dealership and was charged an additional 900.00 for a compleat service and prep. I also had the Screamin Eagle hydraulic tensioner cam plate and HV oil pump installed. So you may be correct that it was flash tuned before I took delivery.

 

I have a 04 Fat Boy with a K&N filter, Vance & Hines Big Shots and S&S 509 cams. After the rebuild the bike was running pretty good but had a surge at lower speeds and was running super lean. I ordered a Power Vision from Fuel Moto with one of their tunes and all issues are gone, couldn’t be happier.

I really like how easy it is to use, and the ability to tune with future mods. I just purchased a 2010 Electra Glide that I plan on turning into a performance bagger and with the PV I can buy an additional license and tune that bike as well.