I have a stock 09 Road King. I am wanting to put a set of slip on vance and hines big oval mufflers on my bike. The store selling the mufflers said that I would not need a tuner to re map the injectors. He said if I added a Big Sucker air intake system then I would need to add a tuner.
My question is this, is he telling me the truth. If I only add the mufflers will I need a tuner. I do not like the way some bikes sound when they back off the throttle and get that sound like it is cracking or popping. Any help would be apppreciated.

 

I have the same problem, all im doing is putting slip ons on my bike. All 3 harley dealers in my area tried to sell me their tuners and try to get some dyno time ect ect. BOTTOM LINE: YOU DO NOT HAVE TO TUNE THE BIKE IF ALL YOU ARE DOING IS ALTERING THE EXHAUST! They also told me the same thing, once you alter the air cleaner yes you then do. Many people have done this and a way of telling if anything is happening is to change your spark plugs when you do the exhaust swap. That way you can tell by the plugs what is going on in your motor (ie fouling due to being rich ect) A good friend of mine has a 08 night train and put on 12000 mi since his slip ons and has no problems at all! Even his spark plugs are wearing normally too.

 

You don't need a tuner for safety. You will loose just a bit or torque and perhaps some edge but there are tons of bikes out there running with just slip ons. You could probably run well enough with the filter change, but you are pushing drivability and performance a bit, and I assume you are putting the cleaner on for performance. If you don't like decel pop then you need a tuner that is sophisticated enough to deal with it. The TTS tuning is the current hot ticket. I was able to easily tune decel pop and a surge out with it.

I would say to install the exhaust and see how the bike runs. Not all bikes and exhausts will decel pop, but the harley exhaust is relatively short and most do. If it turns out you don't like the pop or crackle or how its running, then get yourself a tuner of your choice, the TTS being a good choice if you are comfortable around a computer. Well you know how to get on this forum, so you are probably comfortable enough.

 

I just read this article in the March issue of American Iron Magazine concerning the installation of a Stage 1 Ness Big Sucker air cleaner on a bone stock 2008 Street Glide.

"Since 2008 and later bikes have O2 sensors in their exhaust header pipes; the stock EFI ECM module adapts this air cleaner change. That means we and you will not have to do any EFI map changes after this install".

The end result was 73.52 HP and 84.96 tq.

I have a SE Nightstick 2 into 1 slipon on my 2010 Road Glide which is 50 EPA approved. I'm just wondering with my exhaust and a Ness Big sucker if I need a tuner.

I have read countless articles saying that the Delphi ECM adjust the fuel automatically by the O2 sensors.

 

As said above, rule of thumb is pipes only, no need for a tuner. Add an air filter too, you need a tuner.

 

Why are you putting the Big sucker on, posing, looks, or performance?

The ECU will adjust close loop and apply some adjustments open loop, but its basis for making open loop fuel calculations, among others, will be off. O2 sensors don't measure A/F directly, the ECU calculates A/F for the rpm and load mostly based on the VE of the engine (how well it pumps air) and the feedback it gets from the O2 sensor. If the VE is off the A/F will be off optimum. It will run, however.

Try the mods if you like, it won't hurt nuthin, and the bike may run well enough for you. But if you are making the mod for performance improvement, you are not gaining much performance, if any, from the free flow AC without a corresponding EFI tune. Changing pipes hurt but not as much as a filter... and the sound may be worth it anyway.