How to improve your bike with a flash tune

Have you upgraded your bike’s exhaust? Replaced the restrictive factory air filter? Chances are you have, and you’re not alone. These are often the first and most popular mods made to many motorcycles to allow the engine to breathe better, sound better, go better and weigh, err, better.

But does your beloved bike really go that much better? As in, has it achieved the performance gains the aftermarket brands claim? The answer is no – at least, not without recalibrating your bike’s computer, better known as a flash tune (reflashing the ECU), to get all the benefits of those changes and make it run the best it can. Without it, those upgrades are only half the story.

Whether you’ve got a sportsbike, a race bike, a learner bike, an adventure bike or a cruiser, let’s look at why your modern motorcycle needs a flash tune. Note: If your bike is fuelled by a carburettor, not EFI, then this does not apply to you.

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Opening the airbox and adding a high-flow air filter and exhaust allows your bike’s engine to draw and better extract more air. More air means a bigger bang, which means more power, doesn’t it? Not exactly. Drawing more air without adjusting the ECU means your engine’s air-fuel mixtures will err towards being lean (too much air and not enough fuel for the engine to burn properly), which typically results in a loss of power and torque, and a very real risk of mid- to long-term engine damage.

The flipside is an engine that runs too rich, which drinks like a sailor, wreaks of fuel and evidenced by the undesirably dark colour of its sparkplugs.

Ask yourself, is my bike:
• Popping and banging on deceleration?
• Hard to start?
• Emitting an excessive amount of heat?
• Feeling laggy or stuttering under mid-speed acceleration?
• Snatchy in its throttle action and more like a light switch instead of feeling nice and linear?
• Feeling as if it’s being pulled in the opposite direction under a steady throttle?
• Running rough and generally difficult to control no matter how smooth my throttle inputs?
• Sapping my confidence?
• Making me grimace instead of smile when I crack the throttle?

If you answered ‘yes’ to any of the above then do your bike and yourself a favour and get a flash tune.

Reflashing the ECU, or a flash tune, involves modifying your bike’s engine control unit, or ECU (it’s also commonly called an engine control module, or ECM). This involves changing fuel and ignition mapping values to optimise performance characteristics around your bike’s upgrades. Combined, it’s a sure-fire way to increase power and torque outputs and characteristics, improve fuel use, engine smoothness and throttle response, and general rideability. In other words, all bikes will benefit from an ECU reflash. But this is no job for the home mechanic. Best leave it to the professionals who’ve invested in expensive and powerful equipment (such as scan tools that read and clear fault codes and diagnose faults among others) and know what they’re doing.

The internet is full of flash files to buy for your bike, but it’s strongly recommended to buy a file designed for Australia.

If you buy a file from the US, for example, and look at the brand’s performance claims, you’re not comparing apples with apples for two reasons. Firstly, the US market traditionally gets diluted versions of many global models, which are exported stateside with restricted performance compared to what we get here in Australia. That means the gains by the American ECU brand claims may not be relevant to us.

The second problem of buying a flash file from the US is the fact that it’s designed around their fuel. North America’s regular-octane fuel is generally 87 RON, and the best they get is between 91 and 94 RON, which is considerably lower than what we can get here.

The octane difference means US bikes need to add a lot more fuel to their engines than what we add. That means if you’re using an American tune here in Australia then your bike will run excessively rich to the point where it will foul sparkplugs and guzzle fuel. The more serious problem you’re likely to face in maybe 5000 or 10,000km time is issues with effectively lubricating the cylinder bore and piston rings, bore glazing, and excessive oil use, all of which ultimately mean an expensive job to rebuild the engine.

You could otherwise have a big build-up of carbon on the valves to the point where the valves start leaking, resulting in a loss of compression and power, and the engine mightn’t start and run as cleanly anymore.

Key takeaway: Don’t be fooled. Get an ECU flash tune from Australia.

Professional ECU tuners and dyno specialists such as Dave Edgecombe of Dynobike, in Melbourne’s south-east suburb of Moorabbin, typically create and test several tunes for each motorcycle model before making it available for purchase. That includes separate tune files for each exhaust brand with each bike model.

“When it comes to choosing what ECU file to buy and where to buy it, you need to look at the overall result and how it affects the riding in general,” Dave says. “Will you get more acceleration and throttle response while riding on the streets? Will the engine run cooler? Will the transition from on- to off-throttle be smoother, more predictable, more linear and, ultimately, more controllable? That’s the difference between a good tune and a bad tune and, ultimately, the difference between a great ride and a horrible ride,” the former Team Honda race mechanic says.

The results of an ECU reflash mightn’t be massive gains in power and torque but rather considerable improvements in how it makes those numbers.

“Don’t get sucked into horsepower claims. How the bike makes its power through the entire rev range – especially down low – is far more important,” Dave says.

“It’s easy to add more power at redline and brag to your mates, but it won’t improve how it rides at 3000 or 4000rpm where you realistically spend most of the time. Instead, you want to improve how it feels on the road, and that’s exactly what an ECU reflash does. It means your bike will run nicer; smoother; it’ll be more responsive; more torquey; it’ll accelerate much harder and it’ll run much cooler. These are the gains you want – real-world gains.”

You can either drop off your bike or send just your ECU to a shop for reflashing. In Dynobike’s case, an Australian flash tune typically costs between $500 and $600.

Furthermore, tuning the bike specifically for its mods on Dynobike’s dyno, for example, typically starts from $895 and, depending on complexity of the bike’s system and the time required, can be as high as $1500 in the case of a Ducati Panigale V4.

Dynos are essentially big treadmills for bikes or cars and an extremely effective tool to measure a host of data such as power and torque characteristics as well as air-fuel ratio – all of which determine whether your bike’s fuelling is lean or rich, thus the best the engine can be.

Good motorcycle tuners spend very little time analysing peak power and torque figures because they know that only occurs at maximum revs and briefly. It’s the rest of the power curve that gets the attention, especially low throttle openings where you need the power to be smooth and controllable to allow you to open the throttle aggressively, inspire confidence and plenty of enjoyment.

So, on your next ride, carefully consider how your bike runs and as yourself the aforementioned questions. Once confirmed, you now know what you need to do. Good luck.

Remember:
• Don’t be fooled. Get an ECU flash tune from Australia.
• Don’t get sucked into horsepower claims. How the bike makes its power through the entire rev range – especially down low – is far more important. Power is nothing without control.
• Check your bike’s warranty – flash tuning and custom dyno tuning may void your warranty.