Power Commander vs. ECU flash: Which is better for tuning your motorcycle?

Which method is better? 

We’ll get to that, but before we do, our lawyers insist we point out that altering your bike’s emissions in any way makes it illegal for road use. Hence, the clear and prominent “race use only” warnings on the packaging of products like exhaust systems and fuel controllers. Also, installing a Power Commander or flashing the ECU may void your factory warranty since it manipulates the stock engine parameters. So consider those two factors before proceeding. 

With that out of the way, you might be wondering why you would want to “put a tune” on your bike in the first place. What’s the point? More power and improved throttle response, mainly, by way of optimized fuel and ignition curves. Because even in stock form, government restrictions, plus liability and reliability concerns from the manufacturer, likely mean your bike isn’t performing as well as it could in, say, a world without speed limits or concerns over greenhouse gasses. 

And of course if you’ve replaced your exhaust system or installed a high-flow air filter, or done any motor mods like a big bore or cams, then you need to tune your fuel (and perhaps ignition timing) to suit the new setup, or you’re leaving power on the table. You also need to tune your fueling to ensure your engine is safe, because if you’re running lean due to changes to the intake or exhaust, you could be at risk of damage. 

As mentioned earlier, to tune a modern EFI bike you either get the ECU flashed, or install a piggyback module like a Power Commander.

“Piggyback” means the unit sits on top of the existing stock hardware, literally. The Power Commander’s wiring harness plugs into the fuel injectors, throttle position sensor, and other sensors and the module manipulates the signals so that the ECU makes the desired changes to the fuel and ignition curves.

More recently, the “flash” technique emerged, and FlashTune is by far the biggest name in this field. With a flash, the code within the stock ECU itself gets rewritten. Basically, the bike’s brain gets fully reprogrammed. 

Look at it this way: A piggyback ECU is like wearing glasses to correct your vision. The glasses alter the light before it enters your eyes so you can see better. With an ECU flash, you’re getting Lasik surgery. They’re going right in there and changing things at the source. 

And because a flash cracks into the ECU programming, that means there are many more parameters that can be adjusted. Sure, you’ve got fuel and ignition control, but a flash can also remove speed limits, change when the cooling fan comes on, or keep the throttle plates cracked just a sliver on deceleration so there’s less engine braking, just to name a few things. And, it does it all with stock components, so there’s no additional wiring or hardware to install.

An ECU flash is undeniably more advanced and streamlined, and generally speaking it costs about $250 to $300 to have a shop perform a flash, which is actually cheaper than buying a Power Commander. 

However, flashes aren’t available for every application — it’s mostly just Japanese sport bikes — and unless there’s a licensed service center nearby to perform the flash, you’ll need to remove and mail in your ECU. 

Alternatively, you can buy a kit to flash the ECU yourself at home. That costs about $380 and you’ll need a PC to run the software. If you’re OK with all of that, then it’s hard to argue with a flash since it’s so advanced. That being said, you have the potential to really mess things up if you get carried away. When it comes to ECU tuning beyond a standard flash, it’s definitely best to go to a professional. 

With a Power Commander, the cost of admission is usually between $350 and $400, and DynoJet has modules for pretty much any bike you can imagine, from dual-sports to cruisers. The Power Commander comes pre-programmed with a base map for your bike, which is nice, and there are plenty of other free maps available to match whatever mods you’ve done, although you’ll need a laptop and the Power Commander software to make changes.

All you have to do is install it, and while the kit has detailed instructions, it’s still a pain since you almost always have to remove the bodywork and tank to plug everything in. However, you can also reverse the whole process and remove the module any time you like and be back to stock, which is nice.  

So which method is better? From a performance perspective, the refinement and comprehensiveness of an ECU flash is tough to beat. It’s cheaper, too, and easier to do, assuming you have a service center nearby (or spring for the DIY kit). However, flashes are only available for limited applications, so it might not even be an option for your bike. In which case, a Power Commander is a solid, proven option for tuning your bike’s fuel and ignition curves.