What is a dyno tune?
What is horsepower, torque and air-fuel ratio?
Does my bike need a dyno tune?
What are the advantages of a dyno tune?
Why are my exhaust pipes black if my bike is running correctly?

What is a dyno tune?
Simply put, a dyno tune is making adjustments to you bikes ignition, fuel and air supply, to achieve the most possible horse power and torque, while maintaining optimal air fuel ratio. To do this we use our state of the art Dyno Jet dynamometer.

What is horsepower and torque and air-fuel ratio?
Horsepower is top speed and torque is what gets us there. Air fuel ratio is how much air and fuel are mixing and entering the combustion chamber. This is how rich or lean the motor is running. Either end of the scale will cost you power, torque, economy, and efficiency. If you get the balance too far out on the lean side, damage can be done to the motor. If you get unbalanced to the rich side, you can foul spark plugs, dilute your oil with gasoline, and generally cause a noticeable reduction in performance.

All motors produced today that are in legal production vehicles have to meet Federal EPA requirements and are generally on the lean side of the scale. Changing exhaust systems, mufflers, air filters, carburetors, and sometimes even spark plugs, affect the way a motor performs. While making these changes may seem like the thing to do, one can end up with problems if these are not done properly. Like today’s cages,(automobiles) it is very difficult to attain the desired goal without the aid of specialized, and usually costly, equipment.

How do I know if I need a dyno tune?
For the most part any motor that has had changes made to the air filter system, muffler and/or exhaust headers, most likely will need to be tuned for the components adder or changed. It makes no difference if you bike is normally aspirated or injected. Both can be dyno tuned.

What are the advantages of a dyno tune?
The advantages of having your bike dyno tuned should become evident at this point. Horse power, torque, air fuel mixture are affected by anything we do to our bike’s motor. A normally aspirated bike has less adjustment range due to the fact that you only have a slow jet, needle jet and main jet. By changing the values of these jets in conjunction with each other, a satisfactory mix of the above values can usually be attained. In other words a dyno tune attempts to bring all aspects of the values needed to make a motor run, into the best possible ratio with each other, giving you maximum power and economy. Naturally, compression, cam lift and duration, valve size and port configuration, spark advance etc. are all needed to complete the picture.

With the injection systems of today and the availability of tunable ECM’s, like the Dyno Jet Power Commander, we can tune your bike to the best it can be with the elected performance changes. Another advantage is that if in the future you make additional changes to the motor a trip to the dyno room can re-map to compensate for the changes.

What other options are there for my injected bike?
There are several options available for Harley-Davidson® motorcycles.
1. Factory Download.
2. Power Commander.
3. Screamin’ Eagle® Race Tuner. Metric bikes / Sport bikes are limited to the Power Commander and other like products.

If your upgrades are limited to adding Screamin’ Eagle® slip fit mufflers, and a high flow air filter system, the factory prepared download will, in most cases, work just fine for you. This is the least expensive option. If you add additional performance options you will have to re-map again and depending on the extent of your modifications, you may not be able to use another factory download.

The Power Commander is a separate unit that is placed in line between the bike’s wire harness and the onboard ECM. This unit tells the original ECM what changes to make in fuel supple, timing, etc., to achieve the desired and expected results. It acts like and interpreter from one language to another. This actually works very well while leaving the factory ECM unchanged.

The third option is the Screamin’ Eagle Race Tuner. This is a program that connects your bike to the computer with a black box, called a key. This key is married to your bike only, and cannot be used on any other bike. This key is the only access you have to your ECM for mapping. This program actually re-maps the factory ECM. This is a good option for a Harley with space problems under the seat. This option is the most costly and takes the most time.

Why are my pipes always black if the bike is not running rich?
When lead was in our gasoline, you could read the mixture by looking at the spark plugs and the exhaust pipe for the rich tan color that spelled a good running motor. Today there is no lead in gasoline so all we have coming out the pipe that deposits is carbon. Carbon is black and builds up like soot on the exhaust pipe causing one to think their bike is running rich when in fact, it may be running lean.

The House of Harley-Davidson & Buell has the top of the line, state of the art, Dyno Jet dynamometer and trained professionals who run the dyno and write maps for your bike. We are a Certified Tuning Center for Dyno Jet and have the state of the art , exclusive Data Link Program from Dyno Jet. This program writes the map in real time as your bike is being run and put under load. You spend a little more up front but the result is a bike that runs at it’s peak for the options you have installed and that your air fuel ratio is a close to optimal s it can be for the selected components you have chosen.
Legal note: Any performance items you add to your bike will change the emissions from your motor. This may or may not be legal depending on the state you operate your motorcycle in. Any Harley-Davidson crossed flag performance parts you install on your Harley-Davidson or Buell bike may affect your warranty.