By Justin Woolich, Specialist Motorcycle Engineer
When your bike is hesitating, when it’s spluttering while you’re cruising a track, that’s not an accident. It’s not a problem with your bike. It’s meant to do that. It’s pre-programmed by default. In a nutshell, you’re not in control of your bike, a computer is. It’s overriding your decision to ramp up the revs because of emissions laws. It’s switching between open and closed fuel loops, so it complies with environmental law. So how does it work?
Please Note: Woolich Racing Products are designed specifically for racetrack performance
Woolich Racing is the top choice for professional motorcycle racers and track riders. Our ECU flashing allows you to tune with more precision across more engine systems. Woolich Racing’s precision tuning, especially tuning that removes OEM settings, limiters and adjusts air-fuel ratios, is designed for track use only. We recommend you seek advice about emissions and other applicable local laws before removing the speed limiter and adjusting your air-fuel ratio if you intend to ride on the street.
How Your Bike’s Air and Fuel Gets Mixed
How well your bike runs depends heavily on the Air-Fuel Ratio (AFR) in the engine. If it runs too rich (too much fuel) or too lean (too much air), it will greatly impact performance. How you ride, the altitude, the temperature, the road… lots of variables will impact how much air or fuel should be mixed. Learn more about Motorcycle Air-Fuel Ratios.
How AFR is controlled comes down to what mode your bike is defaulting to.
How Air-Fuel Ratio is Determined Inside Your Bike’s Engine
Two ways, open and closed fuel control. Open is controlled by the pre-programmed “instructions” (or maps) in your bike’s computer. Closed is controlled by (nearly) real-time monitoring in the engine. Both have limitations, and switching between the two has its own problems.
Closed and Open Loop Fuel Control in Motorcycles
The lambda sensor, its fuel controller, and the bike’s ECU (computer) use different measurements to decide roughly what the best air-fuel ratio is at any given time.
Closed Loop Fuel Control
Closed Loop Fuel Control is where a lambda sensor monitors your engine’s output for inefficiencies in air-fuel ratio and adjusts it by “looping back” information to the fuel controller. It’s all about being super fuel efficient (and compliant with emissions laws at the time of manufacturing). Your bike will automatically go into closed loop mode when you’re not putting many demands on it. This is to limit emissions so the bike complies with environmental laws.
Provided your bike has a quality lambda sensor and everything is working as it should, it will perform an automated compensation if it finds signs of a too rich or too lean AFR. Lambda sensors live a hard life. For this reason, it may be among the first things that need replacing on your bike. When it’s wearing out, your bike’s performance problems will get a whole lot worse.
Open Loop Fuel Control
Open loop is where your bike defaults back to the standard instructions installed in the ECU by the manufacturer (or your dyno tuner). These instructions are your motorbike’s ECU maps. Learn more about Motorcycle ECU Maps here. While your ECU may use signals from the Lambda sensor (among other signals), the lambda is no longer in control of the air-fuel mix – the loop is open. ECU mapping at a manufacturing level must comply with state and federal (and international) emissions laws.
Problems with Relying On ECU and Lambda Sensors to Manage Air-Fuel Ratio
In short, a computer is riding your bike for you. It has control, not you. And that’s mostly because it has been programmed to pass combustion efficiency tests on the factory floor.
Poor fuelling is an issue that harks back to long before emissions restrictions. But wow, they’ve escalated the issue. Emission restrictions and our obsession with mileage mean your bike’s performance is compromised on purpose at the manufacturing level. The default on a lot of makes and models is overly aggressive open to closed switching. To pass emissions laws, your manufacturer has programmed your bike to revert to closed loop fuel management, aggressively and often. What does it feel like? A sudden jerk while you’re cruising at a constant speed. Your bike may feel unresponsive or hesitate when you ramp up the revs. This is the bike trying to override its pre-programmed instincts.
How Can You Take Back Control of Your Bike’s Performance?
When you’re heading to a race track, you can use Woolich Tools to reprogram your bike’s brain to optimize for performance. You can’t remove your O2 sensors without creating a bunch of problems in your bike’s computer. You can install an O2 sensor modulator that tricks the computer into giving your bike more fuel – but this completely eliminates closed loop mode – which means you’ll be burning a whole lot of fuel, even in idle. Both these options have downsides that can turn into expensive fixes and new performance problems.
Undo Your Bike’s Default “Brainwashing” On The Track
When Justin Woolich told his parents he’d be an engineer, they probably pictured him in a fancy office. Instead, he spends his days on a dynamometer, hacking into motorcycle computer systems. No, it’s not illegal to reprogram your ECU. ECU Flashing is where you change the default “rules” programmed into your bike’s brain to overcome problems like aggressive fuel control and top speed limiters, and to max out the bike’s performance for use on a race track only. ECU Flashing brings your aftermarket exhaust or upgraded throttle into the mix so your bike works with the customizations to produce the ULTIMATE performance results.
Do Our FREE Course in DIY Motorcycle Flashing
Is Motorcycle ECU Flashing Worth It?
There are a thousand “piggyback” options on the market, where you can install some code that tells your bike to do something differently. They will help, but the results are limited. Woolich Racing ECU Flashing is about TOTAL control of your bike. You can tune it to the limit of performance. That’s why so many world champion riders choose Woolich.
Is it worth it to not feel that chug? Is it worth it to shave off a few seconds going zero to sixty? Is it worth it to optimize your gear changes to precision perfection? That’s up to you. We believe that it’s your bike, and you should be able to ride it your way. Woolich Racing is how you do that.