Do I Need A Tuner?

For most riders, when they get a bike, that start making changes. Some of those changes may be cosmetic, comfort, or performance oriented. These changes / upgrades leads to the most common questions I get..."Do I need a tuner?". The answer, can vary greatly depending on what changes you are making. This is a quick overview of what a tuner is, the types of tuners, some scenarios of when you do or do not need a tuner, and some things to be aware of.

What Is A Tuner?

A tuner is a device that is used to adjust the air to fuel mixture, throttle response, and change the ignition timing and on your motorcycle. Tuners are used to improve the performance of the engine and improve running quality when changes are made to the engine. If you have a professional tune your motorcycle, they will add a tuner, and use that to upload a base map. A map is a program or software that is uploaded to the computer on the motorcycle that will make adjustments. Some maps will make actual adjustments or try to trick the computer to get the desired result. After the base map is uploaded, they will tweak and fine tune the programing to optimize the performance of your motorcycle. This will usually involve the use of a dyno to get real readings of horsepower and torque throughout the RPM range. There are some great shops out there that do an outstanding job of optimizing performance.

The truth is that there aren't many performance combinations that have not already been tried. That means that there is a very good chance that the correct map for your motorcycle and upgrades already exist and simply needs to be uploaded. Maps are usually provided with the tuner or available for download. This, paired with the fact that most riders make the same basic modifications, makes tuning your motorcycle very Do It Yourself friendly. Assuming you have a basic mechanical knowledge, of course. If you do not feel confident, seek a professional.

Types of Tuners

There are three basic types of tuners. The first is a tuner that simply flashes the computer, or Electronic Control Module (ECM). This tuner is attached to the motorcycle and is used as an interface to a computer to upload the correct map. The older style of Harley-Davidson tuners (Pro Street Tuner and Pro Race Tuner) are some of the most common examples. Usually, these types of tuners are married to the motorcycle once they have been connected. That means they can not be used to tune multiple bikes. So, be extremely cautious about buying a used tuner.

Another type of tuner is a Piggy Back Tuner. This type of tuner will stay attached to the motorcycle. These tuners might be controlled by an app, which will allow you to customize the parameters of the engine. A Vance and Hines Fuel pack and Dynojet are great examples.

Finally, there are tuners that simply replace the ECM. Replacing the ECM gives you the most control allowing you to change many aspects of the performance of the motorcycle. These tuners allow you to fully capitalize on the performance upgrades you have made to your motorcycle. ThunderMax, is the king of the hill in this segment.

So, Do I Need A Tuner?

Now, that we have covered the basics, let's get to the question at hand, Do you need a tuner?

As a rule of thumb, if you are changing the air flow through the engine, then yes, you need a tuner. Let's go through some scenarios of air flow:

• Stock air cleaner, stock head pipe (with catalytic converter), and slip on exhaust

  • No tuner needed. You are not changing air flow, because it is the stock air cleaner and the converter is the most restrictive part of the exhaust. Adding a tuner wouldn't hurt, but no use spending money if you don't have to.

• Performance air cleaner, stock head pipe (with catalytic converter), and slip on exhaust.

  • Yes. You are increasing air flow because of the air cleaner

• Stock air cleaner, with full exhaust system (replaced head pipe)

  • Yes, you are increasing air flow due to the full exhaust system.

• Performance air cleaner and full exhaust system

  • Yes, this one should be obvious by now...more air in and out.

There are some upgrades that always require a tune. If you increase the displacement of the engine, change the cam, or the throttle body, you will need a tuner. All of these changes are major and require recalibration.

In summary, the answer to the most asked questions about a Harley-Davidson is probably. Tuning a motorcycle, even a stock bike, can see some performance improvements. As you upgrade, a want may become a need. The cost factor is often a consideration when upgrading your bike. Be sure to account for the tuner when making the decision.

A Few Precautions

If you decide to make some upgrades that requires a tuner, but do not tune the motorcycle or do not tune it properly, there are several possible outcomes. First, you may not realize the full potential of the upgrades. If you spend the money for an air intake and slip ons, the bike will still run, it just won't fully take advantage of the upgrades you have done. You might experience some popping or backfire. The more you modify your engine without a tuner, the worse it will run and you risk harming your engine.

The EPA has really been cracking down on the tuner market. Because of this, some tuners on the market will not allow you to retune for a cam change. So, be sure you read the descriptions to ensure the tuner you are looking for will meet your requirements.

You will also see that some tuners, like a lot of performance upgrades, will say "For track use only", or "Not for use on public roads". If you live in California, these restrictions are even more severe. Obviously, there are a lot of bikes out there running track use only components on the street. My advice is always to follow the law, but it's your decision to make. You should also be aware, that turning a motorcycle with an aftermarket tuner could void certain aspects of your warranty. If your motorcycle is tuned with an aftermarket tuner and you take it to a Harley-Davidson dealer, your VIN could be blocked. That means that if they connect your bike to the computer, the computer will detect a change in the program outside of specifications and Harley-Davidson will automatically be notified. Dealers do not want you to loose warranty coverage and many will make suggestions or at least give you a heads up to the possibility. With that being said, if you have a bike and the VIN is blocked by Harley-Davidson, that does not mean you have no warranty. It just means any warranty repairs must be authorized prior to repair. They do this to evaluate if the change you made could have caused the failure. If so, they will deny the claim. If you have an issue with an unrelated system, you would still have coverage. So, you put a hot cam in and tuned the bike, then the radio quits working, the radio would still be covered because it isn't related to changes you made.