Q: What will having 2WDW flash my motorcycle's ECU actually do for me?

A: All modern motorcycles come with some form of restriction(s) built into the stock ECU mapping in one form or another for emissions compliance. Whether those restrictions come in the form of electronic throttle restrictions, ignition timing restrictions, and/or lean fuel mapping for emissions compliance is specific to each motorcycle's year and model. In most cases, ALL of those restrictions are present to varying degrees in Euro 4 and Euro 5 emissions complaint motorcycles (ESPECIALLY for US production models). With our ECU flash, all of those restrictions are removed.

Furthermore, installing aftermarket intake and/or exhaust components to improve airflow through the engine are incredibly popular modifications that many owners choose to make to their motorcycles, but without appropriate custom ECU mapping to match the improved airflow provided by those parts, the bike simply won't ever run as well as it should. With our custom ECU mapping, built SPECIFICALLY on our dyno for your motorcycle's EXACT aftermarket intake/exhaust combination, your engine's peak performance, throttle response (and on/off throttle transition smoothness), and longevity will be improved. In other words, this means that your bike will simply run smoother, stronger and cooler than it ever has before!

To better understand the performance improvements that will be made to your specific motorcycle with our ECU flash, check out the example dyno graph(s) listed in the Mail-In ECU Flashing Service product description for your specific bike.


Q: Do I “need” to flash my ECU if I modify my intake and/or exhaust system?

A: No, this is America and you can do whatever you want! USUALLY, flashing your ECU isn’t “necessary” in the sense that NOT doing so will somehow cause immediate and catastrophic damage to your engine (in most cases). That said, not having appropriate custom ECU mapping for your motorcycle's specific intake/exhaust modifications can SIGNIFICANTLY shorten the life of some expensive internal engine components, such as the pistons and valves.

In our opinion, the better question to ask is why would you NOT want to flash your ECU, remove any emissions restrictions and have custom ECU mapping to match your bike's specific intake/exhaust modifications?!


Q: Won’t my bike “self-adjust” for my new intake and/or exhaust system?

A: Not very well. Most modern motorcycles do utilize at least one O2 sensor that controls what is known as “closed loop operation”. Closed loop operation only controls VERY small portions of most motorcycle’s engine throttle, RPM and load range. Your bike’s O2 sensor(s) are also set to maintain a fixed, lean (generally 14.7:1) air:fuel mixture for emissions purposes, which is not optimal for performance, throttle response, or engine longevity. Once your bike’s throttle opening percentage, engine load and/or engine RPM exceeds the closed loop operation parameters (this is usually above only 10-15% throttle and roughly 1/3 of the way through an engine’s RPM range) the O2 sensor input is ignored in what is known as “open loop operation”. In open loop operation, without the input of the O2 sensor(s), the bike has no way of knowing that it needs to be adjusting fuel delivery for any modifications that you’ve made to the bike!


Q: Can I leave my O2 sensor(s) in place when I flash my ECU?

A: In most cases, no. The O2 sensor(s) should, almost, always be unplugged and closed loop operation disabled. Closed loop operation, as explained above, is already sub-optimal for most motorcycle engines from a performance, throttle response and combustion temperature standpoint. If not unplugged, the O2 sensors will allow closed loop operation to interfere with the custom mapping that we flash into the ECU, and throttle response and/or transition will not be nearly as smooth as it should be! There are some exceptions to this, as some motorcycle models’ closed loop operation can actually be manipulated and/or overwritten with our ECU flash, and some select models actually still function very well with closed loop operation maintained and fully functional for a number of different reasons.

Whether or not you need to physically unplug your O2 sensor(s) from your bike's wiring harness is listed as a NOTE in bold in each specific year/make/model's ECU Flashing Service product description. After reading those notes, if you still aren’t sure if your O2 sensor(s) should remain plugged in after your ECU has been flashed, send us an email and we’ll be happy to confirm one way or another!


Q: If my bike’s O2 sensors(s) are unplugged, how will my bike adjust for my specific environment and/or climate?

A: All modern fuel injected motorcycles are equipped with other input sensors (such as intake air temperature sensors and barometric pressure sensors) that still play a significant role in BOTH closed loop AND open loop engine operation fuel mapping algorithms! These other input sensors are left completely operational in ALL cases by our custom ECU flash, and they adjust for specific environments and climates extremely well. We actually tested several of these sensors in one of the most extreme riding conditions on the planet when we were supporting several racers and teams at Pike’s Peak, and they provided perfect fueling adjustments for the extremely wide variety of atmospheric conditions we were able to subject them to in this environment. In fact, almost all of the barometric pressure sensors we tested provided accurate fueling adjustments until around 10,000 feet up!


Q: Do I need to use different fuel in my motorcycle once my ECU is flashed?

A: All of our custom ECU mapping is built for 91-93 octane premium pump gas (E10), which is what most motorcycle manufacturers recommend using for almost all models. Using lower octane and/or quality fuel is NOT RECOMMENDED!


Q: Do I need to block off my AIS/PAIR system?

A: In most cases, your bike’s AIS/PAIR system (the stock air-injection system equipped on most modern motorcycles for emissions compliance) should absolutely be removed, plugged or blocked off in some way! Once an aftermarket performance exhaust system (without a catalytic converter) is installed on your bike, this system can cause significant backfiring on deceleration. It may sound "cool", but it is quite hard on the exhaust valves and will eventually blow the packing right out of your muffler. It also negatively impacts throttle response and smoothness by interrupting your engine’s normal exhaust pulse flow and velocity. In some cases, the AIS/PAIR solenoids used are “naturally closed”, which means that when we disable this system through ECU flashing software, the solenoid remains closed and no air can pass through the system! Unfortunately, most AIS/PAIR solenoids are “naturally open”, so when the system is disabled the solenoid still allows air to pass through the system. In these cases (most motorcycles fall into this category) the AIS/PAIR solenoid feed line should be plugged with a vacuum cap to prevent air from flowing from the airbox to the air injection solenoid. If you want to remove the system entirely, you can do so without issue once we flash the ECU, and you can simply install block off plates in place of the system! 

Whether or not you need to plug/block off your bike's AIS is listed as a NOTE in bold in each specific year/make/model's ECU Flashing Service product description. After reading those notes, if you still aren’t sure if you need to plug/block off your AIS after your ECU has been flashed, send us an email and we’ll be happy to confirm one way or another!


Q: So how does the Mail-In ECU Flashing Service work?

A:To have us flash your ECU, simply complete the following steps:

STEP 1: Place the order on our website for your specific year/make/model motorcycle.

STEP 2: Remove your ECU and ship it to us at:

2 Wheel DynoWorks

13209 NE 126th Pl
Suite 460
Kirkland, WA 98034


Note: When mailing in your ECU, please include a note with your contact details and list of any pertinent engine, intake and/or exhaust modifications done to your bike. You may include this note in your package or email it to

STEP 3: Receive and reinstall your ECU, and enjoy your flashed and tuned motorcycle!


Q: What if I’m local and just want to bring my bike or ECU to the shop in person?

A: No problem at all! We welcome walk/ride-in ECU flashing anytime during our regular business hours WITHOUT an appointment for most models. Some ECUs require quite a bit of labor (up to an hour) to remove & replace from your motorcycle. In these cases, additional labor charges may apply. Feel free to give us a call if you're going to ride your bike to our shop for us to flash your ECU, and we'll let you know if your ECU requires additional labor for us to remove & replace and what those labor charges may be!


Q: Why should I have you guys flash my ECU instead of someone else?

A: In the past decade, we have flashed more motorcycle ECU’s than anyone else on the planet for one main reason: ALL of our custom fuel and ignition mapping is built specifically for each motorcycle and intake/exhaust combination that we offer flashing support for! For throttle-by-wire motorcycles, our custom throttle mapping has been developed after thousands of hours of feedback and testing from riders on the street AND professional racers on the track. The combination of the custom fuel and ignition mapping that we build for each setup on the dyno, in conjunction with our custom throttle mapping, provides the smoothest AND strongest engine operation possible throughout the ENTIRE RPM range. On top of all of that, we offer FREE mapping updates for any future modifications you make to your motorcycle AND any improvements we make to our custom mapping through our constant R&D process. Building custom ECU mapping on our dyno is what we specialize in, so we are CONSTANTLY creating new custom mapping as new motorcycle models, intake and exhaust systems are released.

We also answer this question, and cover our ECU Mapping R&D Process MUCH more in depth in this video here:


Q: Will I have a check engine light on after I have my ECU flashed? 

A: In most cases, you will NOT. In SOME cases on newer Euro 5 emissions-compliant models, you may have a TEMPORARY check engine light on after reinstalling your flashed ECU. If this is the case for your bike, it is listed as a NOTE in bold in specific year/make/model's ECU Flashing Service product description. In NO case will the check engine light negatively impact performance until it clears.


Q: Can I get a "flame" or "pop/crackle" tune for my bike? 

A: Not from us! All of our 2WDW custom ECU mapping is designed to both improve engine performance AND increase engine longevity through proper combustion AFRs (air:fuel ratios) and ignition timing for each specific bike's exact exhaust and intake combination. "Flame" and/or "pop/crackle" tunes do NOT improve engine longevity; in fact, this type of ECU mapping WILL REDUCE THE LIFE OF SOME INTERNAL ENGINE COMPONENTS. The flames and/or popping that occurs from this type of tuning is known as "afterfire" and is a result of improper and/or late fuel combustion in the engine. We do not, and will not, ever offer any tuning service that is detrimental to the longevity of an engine.


Q: I don't see my specific year/make/model listed on your website. Can 2WDW still flash my ECU?

A: In many cases, YES! For the most part, we ONLY list bikes on our website when bench harnesses are available for the ECU, so riders can simply send us their ECUs via our Mail-In ECU Flashing Service. When a bench harness is not available, we generally need the whole bike physically in our shop in order to flash the ECU directly through the diagnostic connector on the bike. If you don't see your specific bike listed on our website, and you'd like us to tune it for you, feel free to email us at We'll let you know what your options are, what pricing for your specific bike's ECU flash and/or dyno tuning will cost, and what our availability is!


Q: How can I get even more information about tuning, or any recommended modifications, for my specific motorcycle?

A: For any ECU flashing/tuning questions about specific motorcycles and intake/exhaust system combinations, please email us at

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