I accidently posted this in the Softail Section, but needs to be here. I changed my pipes on my Fatboy 06 to Vance Hines Big Short Shots. The Harley dealer stated that after the 1000 miles check up to have it dyno'd. The bike exhaust has been popping (but getting worse) and today it backfired. The bike seems to be running rough. What should I do? Is this a service problem or the dyno?

Thanks for the help,

Ride Safe

 

What fuel management unit are you using?????

Kinda important......

'cuz if you are just running the Stock or even a Stage flash to the ECM, you need to get either a PC or SERT to fix it first, and use the Dyno time to Dial it in....

 

Bob:
To be quite honest, I do not know.

When I changed out the pipes, the dealer also, did a stage 1 exhaust. I hate to sound like a dummy (my first bike). I am really not mechanical-but learning fast. Where would I get the info that you asked?

Thanks.......

 

You just told me what I needed to know.....

The reason that your bike is running like crap is that you are using an incorrect Fuel / Spark map....

See, the Stage I ECM Program that your dealer installed into your bikes ECM (Computer), was designed for a SPECIFIC Performance package... SE A/C unit, and SE Race Muffler (If it is the Stage I Race).... If it is Stage I Legal, then it is only for the A/C Unit, no mufflers....

Sorry, but I think that your dealer should have at least Kissed you for doing that flash with those pipes.....

No one in their right mind does that, unless of course they don't care about the customer......

Now that you have installed a set of V&H Pipes, that ECM Programming is useless, as it can't compensate for the additional flow/lack of backpressure ......

What you are left to do is decide what kind of Fuel management system (Power Commander, SE Race Tuner, Fuel Pack, Digital Fuel Optimizer, etc....) that you want/need to use to get your motor to work with those pipes.....

Have I painted a picture that you can understand?

 

Yeah Bob!

They sold me an incomplete package. Is there a specific performance package that should be with the Stage 1 OR what fuel package would be the best??? Can I install the fuel package or do I need to bring it in to a service center?? Not being an experienced buyer and mechanic, I am learning lessons, but you would think the dealer would have done the right thing knowing that I would not know.

So, if I had paid for a dyno, it would have been a waste of time???[:@] Is the dyno then done after the performance package is installed??

Thanks for the info......................

 

With your build (SEAC, V&H, 1450) I'd suggest the SERT (Screaming Eagle Race Tuner)......

Keep this in mind.... It allows the Tuner to manually manipulate the data in the ECM to compensate for things that are not in the Stage Package realm....

Example is your build.... A stage I Race for an 06 bike is SE A/C and SE Pro Performance mufflers ONLY!!!!!!!

Now that the entire exhaust system has changed, there is a different dynamic of the exhaust flow, which will lead to Lean pop (Actually it is unburnt fuel in the exhaust that is superheated and then explodes in the pipe)... Left unchecked, you will damage your motor (Burnt pistons, excess heat leads to oil consumption, rider discomfort)...

All your motor is, is an air pump... It can only bring in so much, but it can only get rid of what it brings in, but to bring in more GOOD Air/Fuel, it needs the exhaust to assist in creating backpressure...

The less expensive alternative is the PC IIIUSB .... same principal as the SERT in how it modifies the ECM data, just a less expensive unit that us plugged into the wiring harness, vice reprogramming the ECM Proper.....

Not all dealerships take pride in what they do... Some of us do....

Research around your neck of the woods, talk to other riders, find out who was pleased, who was pissed about their tuning experience....

Check out some of the shops, ask the tough questions, namely "Will it run RIGHT?"

And yes, if they put it on a dyno, it would be more $$$$$ gone, and probably not even cab fare when you went out the door.....

 

Shop around to try and find some one familiar with the new Fuel injection.Alot of old school mom and pop shops where I live like to hock the DFO/TFI type fuel enrichening systems.These work fine if you only need to add fuel but they can't do anything else.I have the DFO on my 06 Dyna and it's practically useless it has no adjustment in the low range and will never eliminate the constant popping and backfiring I'm getting with my SEAC and Thunderheader.However if you don't have the closed loop fuel injection or very agressive intake and exhaust mods they may work fine.Older versions of the DFO for the non closed loop FI have more adjustability.If you want the best get a SERT and get it dynoed.