Electronic Throttle Mapping

Let's talk about throttle control, and how we can make yours smoother. Just about everyone has heard the old saying "slow is smooth, smooth is fast" at one point or another, and when it comes to throttle control on a motorcycle that phrase couldn't be more accurate! Being able to precisely control your throttle opening when exiting a corner is vitally important, both in terms of rider safety AND when looking to shorten lap times at the track.

When exiting a corner on the track, the goal is to get to WOT (wide open throttle) as fast as possible, for as long as possible before you hit the braking zone of the next corner. That said, if the throttle opens too soon, you run the risk of losing rear tire grip at higher lean angles, or you could cause the bike to "stand up" and run wide when exiting the corner. At best, you have to roll back off the throttle to correct your line, and at worst you could experience a crash. This is why, on electronic throttle motorcycles, we spend MORE TIME dialing in and perfecting the ECU's throttle mapping than we do on almost ALL OTHER MAPS (fuel, ignition timing, etc) added together! 

There's two different types of electronic throttle control systems that almost all manufacturers use to control throttle plate opening on modern fuel injected motorcycles. The first (and arguably more antiquated) is an STP (secondary throttle plate) system. With this type of throttle control system, there are two throttle plates on top of each other in each throttle body; one is still 100% mechanically controlled by throttle cables and your wrist while the other is 100% controlled by the ECU. This means that (for example) even when your wrist is giving the bike a WOT input, the STPs may not be anywhere near fully open. In fact, on some models, the plates may NEVER fully open in some gears with stock mapping. These older STP systems generally don't cause the same "twitchy" or "jerky" sensations that the newer electronic throttle systems are notorious for, but they almost always leave a LOT of performance on the table when stock ECU mapping is still in place. These systems have been in place for nearly two decades on some models, such as GSXR600/750s, pre-2017 GSXR1000s, ZX6Rs, pre-2016 ZX10Rs, and many more.

The second, more modern, electronic throttle system is the fully-ETV (electronic throttle valve) style. With bikes utilizing full ETV systems, there is ZERO mechanical connection between what your wrist is doing with the throttle tube on your right handlebar and what's ACTUALLY happening with the throttle plates in the bike's throttle bodies. These systems were first brought into the mainstream by Yamaha with the R6, R1 and most of the FZ/MT model lines; now, these systems are used in nearly every manufacturer's flagship hypernaked, sport and supersport models! They allow the manufacturer to very easily set limits on throttle opening for emissions purposes. They also allow for multiple "rider modes" that have become incredibly popular on most newer models, and they allow for sophisticated TC (traction control),SC (slide control) and LC (launch control) systems! Unfortunately, they are also the cause for just about every rider's frustration when they purchase a newer bike, as they often cause very "twitchy" throttle responses and abrupt on/off throttle transitions. 

Most "tuners" are only utilizing ECU flashing software to simply remove the restrictions put in place by the manufacturer's stock ETV mapping, in the example shown below, which only allows for ~70% throttle opening about 10,000 RPMs when you're actually requesting 75-100% throttle with your wrist!

To accomplish removing these restrictions in the example shown above, only 24 points in a throttle table of 900 points (30x30) are adjusted. In fact, this is EXACTLY what is done with most of the generic "unrestricted" files you can find online for free. This is also why, in most cases, your throttle will still feel "twitchy" or "snatchy" from other tuners, because over 95% of your throttle mapping is still STOCK.

Removing this restriction is a good start, and necessary, but it does absolutely nothing to address the twitchy throttle response throughout the rest of the throttle and RPM ranges/positions! As we said previously, getting to WOT for as long as possible between corners is the ultimate goal, but you first have to be able to GET TO WOT as smoothly as possible. To accomplish this, THE OTHER 876 POINTS (when talking about the single example map shown above) need to be adjusted, and there is anywhere from SIX to SEVERAL DOZEN OTHER throttle maps that are referenced by the ECU at any one time depending on what gear you're in, rider mode you're using, and what TC/SC settings you've selected on the dash! With our custom mapping, almost every single throttle map and parameter is adjusted.

There also isn't a one-size-fits-all approach to smoothing out throttle mapping. Decreasing requested vs given throttle values in many areas will simply result in a more sluggish response, and increasing them in other areas can yield even worse results. At best, when you increase these values too quickly, you'll cause the engine to "bog" due to the overly-quick throttle opening actually REDUCING intake velocity at lower RPM ranges in many modern engines. At worst, you can create an even twitchier and more uncontrollable throttle response than what's in place from the factory!

We've spent COUNTLESS hours on the dyno AND on the track testing, tuning and dialing in our custom throttle mapping for every bike that we offer ECU flashing support for (regardless of which electronic throttle system the bike utilizes). For guys riding/racing at the track, the end result is a MUCH smoother transition from "off-throttle" engine braking to "roll-on" throttle response, which allows for MAXIMUM acceleration through corner exit to WOT with MINIMAL disruption to the chassis. For street riders, this will simply feel like a much "easier" riding experience when riding through busy city streets or navigating traffic on the highway! 

To unrestrict AND smooth our your throttle mapping, select your bike with the year/make/model filter on our homepage and purchase an ECU flash! If you have any questions about your bike's specific electronic throttle control system, the limitations of that system's stock mapping, and what we do to unrestrict AND smooth out that mapping, please email us at support@2wheeldynoworks.com.