The GYTR Power Tuner allows you to quickly and easily alter your fuel and ignition mapping on fuel-injected Yamaha’s. The compact tuner can fit in almost any tool box and holds up to nine different maps while only requiring AA batteries for power. To allow for optimum customization, it features nine separate adjustment points for both the ignition and fuel maps ranging using throttle position and RPM to determine the point. In addition to changing your mapping, you can also view the run time on the motor, adjust your idle timing, and monitor several different sensors while also having a self-diagnosis function. The tuner works with the current YZF’s, YZFX’s, and also the WR’s; however, a GYTR Competition Kit/ECU is required for the WR models.
There is a lot of overlap in the specifics to how the tuner works but broken down the fuel is adjustable in 3% increments per number change for a range of 42% overall or 21% richer or leaner. Ignition is done in 1 degree steps per number change for a 14 degree range with 4 degrees allowed in advance and 9 degree steps in retarding the ignition timing.
Yamaha’s GYTR Power Tuner is a very simple tool to use. Basically plug and play. With only six buttons and one of them being the power button, it makes it difficult to mess anything up or get confused. However, when utilizing the tuner, plugging it into the bike then powering the unit works the best. When plugging in the tuner while it’s on, it would often shut down and not work properly. Making sure the ECU is “hot” is also advised, so having just run the bike so that the ECU is not powered down will eliminate confusion. Also, the plug is easily accessible on the bike with it being mounted right in front of the airbox.
When customizing a map, it allows you to change the fuel and ignition maps in the low, mid, and high RPM’s at ⅛, ⅜, and ¾ throttle positions. This gives you nine different changes for each of the nine different stored fuel and ignition maps to fine tune a specific setting to your liking. Additionally, with the ability to have nine different maps, it allows you to create several maps and try them back-to-back.
Learning the programming and the buttons of the unit is simple. But then some of the questions it asks you to confirm or the wording is a little awkward until you learn it. Like most devices it is quickly learned and the function is fast. It takes about five minutes to create a map from scratch when you understand the system. Building a few and having them ready to go is the best way to test.
The whole process of switching maps takes less than a minute. Even small ignition and fuel changes are capable of changing the power characteristics drastically. It really changes the character more than the actual power, but we’re sure a dyno would tell you more specifically about this. We don’t ride dynos, but the changes definitely made some of the bikes feel much more (or less in some cases by design) powerful on the track.
We used the unit on just about every FI Yamaha dirt bike we’ve had. The Power Tuner can make a WR aggressive and a YZ tame, if deseired. It can help an aftermarket even work even better and or fine tune the delivery of power. It can improve fuel economy or make it worse too! And there wasn’t a YZ, FX or WR that did not benefit from having this unit plugged into it.
For example on our YZ250F, employing an aggressive map, it was a very noticeable change from the stock map. It gave the 250 a little bit more power and revved out quicker which some riders preferred. Contrarily, the smoother, less aggressive map didn’t provide much of a change from stock and wasn’t preferred by anyone.
On the YZ450F and YZ450FX some or our riders were creating less aggressive maps, especially in the low RPM and low throttle position zones to tame the power and make the bikes easier to ride. In the upper zones even some of these maps were tuned to be more aggressive in effect making the power more progressive. All in a matter of minutes though testing out all the options takes some time.
On WRs with the competition ECU installed we were all over the place depending on the conditions and setup of the bike. Most changes were actually to accommodate for a less restrictive exhaust by leaning out the fuel in most cases. Or when running the stock very quiet muffler, tuning the ignition maps for some additional throttle response.
It is pretty easy to know how to change the maps if you think about the power character you are looking for. The simple way to look at it is fuel adds traction, so more fuel = more traction. Ignition is throttle response, more aggressive ignition = more aggressive throttle response. This works to a point until it just becomes rich, lean, sluggish or in some cases detonates. The unit has pre-set parameters to keep you pretty safe. And after trying a few setting, like suspension testing, most riders get a feel for the possibilities and really appreciate the usefulness of this tool.
The GYTR Power Tuner is basically the single best tuning tool you can have for YZ and if equipped, WR. It's so nice to be able to tune without getting gas on your hands or needing lots of tools or a full-blown laptop computer at the track. Considering the cost of a new exhaust system or engine work, it is pretty cheap as well with its sub-$300 price tag. It will allow you to get the most from your engine no matter how you want that “most” to be delivered. The tool can be shared between bikes and it is simple enough to make changes at the track in a matter of minutes. Changes equal to swapping an exhaust or throwing in different cams. And after buying the unit, each change is free!
