Should I be using a tuner?
Seasoned HDF Member
Joined: Sep 2009
Posts: 17,145
Likes: 6,168
From: SE Michigan
First, probably not, 2nd, how long have you been riding in this configuration? 3rd, I doubt your bike will blow up if you don't use a tuner, 4th, what is a brother slip on?
Seasoned HDF Member
Joined: Sep 2008
Posts: 14,143
Likes: 11,212
From: San Diego, CA
I'm assuming you have an EFI bike, not a carb, correct....???
If so, your 2004 Delphi ECM runs an all open loop tune. That means that the entire tune is based on algorithms derived from the OEM parts put on that engine. You do not have any O2 sensors, so there are no real time adjustments made to the AFR in the cruise portions of your tune...
You have increased the airflow to the engine, without "telling" the ECM you have done that... You will be leaner in all areas of the tune, and could be very lean in the critical areas of the tune (high load/high RPM)...
If you ride easy, you would probably have no issues.... If you are a spirited rider, ride two-up with gear a lot, or "drive it like you stole it"... You will be very lean in areas of the tune and could cause damage to your engine...
This topic is hotly debated... but I always change the tune, when I change the airflow of the engine... on any of my EFI bikes..
In some cases it just makes the bike run better, and in some cases it makes the engine run safer... sometimes a lot safer...
Your choice, but IMHO.... retune the bike...
Good luck with your decision...
Last edited by hattitude; Jul 18, 2022 at 07:03 PM.
Seasoned HDF Member
Joined: Mar 2012
Posts: 5,157
Likes: 740
From: new caney, tx
People say yes, and people say no. Let the bike tell you. You will know if it's acting differently, we won't. Despite what other may say, when most of us add an intake and exhaust we add a tuner. The bike can learn some stuff based on what you have added but it can only do so much within its capabilities.
Cruiser
Joined: Feb 2021
Posts: 186
Likes: 38
From: bendigo
hattitude is correct but i think your bike is carbed? if so it would be running lean. could be very lean. How long have you had the bike. Lean engines can run quite well but do damage, if very lean. If someone else fitted the freer breathers they might well have re jetted. Pull a plug and see what it tells you. If in doubt get it checked.
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Cruiser
Joined: Jan 2015
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From: ohio
I'm assuming you have an EFI bike, not a carb, correct....???
If so, your 2004 Delphi ECM runs an all open loop tune. That means that the entire tune is based on algorithms derived from the OEM parts put on that engine. You do not have any O2 sensors, so there are no real time adjustments made to the AFR in the cruise portions of your tune...
You have increased the airflow to the engine, without "telling" the ECM you have done that... You will be leaner in all areas of the tune, and could be very lean in the critical areas of the tune (high load/high RPM)...
If you ride easy, you would probably have no issues.... If you are a spirited rider, ride two-up with gear a lot, or "drive it like you stole it"... You will be very lean in areas of the tune and could cause damage to your engine...
This topic is hotly debated... but I always change the tune, when I change the airflow of the engine... on any of my EFI bikes..
In some cases it just makes the bike run better, and in some cases it makes the engine run safer... sometimes a lot safer...
Your choice, but IMHO.... retune the bike...
Good luck with your decision...
If so, your 2004 Delphi ECM runs an all open loop tune. That means that the entire tune is based on algorithms derived from the OEM parts put on that engine. You do not have any O2 sensors, so there are no real time adjustments made to the AFR in the cruise portions of your tune...
You have increased the airflow to the engine, without "telling" the ECM you have done that... You will be leaner in all areas of the tune, and could be very lean in the critical areas of the tune (high load/high RPM)...
If you ride easy, you would probably have no issues.... If you are a spirited rider, ride two-up with gear a lot, or "drive it like you stole it"... You will be very lean in areas of the tune and could cause damage to your engine...
This topic is hotly debated... but I always change the tune, when I change the airflow of the engine... on any of my EFI bikes..
In some cases it just makes the bike run better, and in some cases it makes the engine run safer... sometimes a lot safer...
Your choice, but IMHO.... retune the bike...
Good luck with your decision...
Hattitude always has good info, but nothing is as good as checking the plugs. It's the best thing you can do and the first thing a shop will do if you ask them. They tell you everything.