One of the first mods anyone does to their bike is changing the exhaust. Generally speaking replacing the stock exhaust makes your bike lighter and sound significantly better, but it also changes the amount of air coming out of the bike.
No matter if it is a Slip-on or a full system, it is important to do some sort of fuel management to go along with it. Since you added more air flow you need to correct the amount of gas being fed, otherwise you’d be running lean (Air > Fuel). If you run your bike lean you may experience hotter than average engines, jerky throttles, and your exhaust may crackle and backfire. Yes, crackling and backfires sound cool but thats not the best thing for your bike.
There are a few ways to address this on fuel injected bikes.You can flash a new fuel map onto your bike’s ECU, install a tuning kit (Rexxer), or install a booster plug. There’s no definitive answer as to which you should choose but I highly recommend choosing one of these options. In a nutshell, your bike will run much better and if you decide to do more performance mods in the future it will make your life so much easier.
What does a tuning kit do?
Installing any form tuning kit will allow you to re-flash your ECU to your hearts content. These kits tap into your bike and basically tell the injectors how much fuel to feed your bike at any given RPM. You can increase or decrease this according to your exact set up. Every setup will be different, it is all dependent upon any performance mod you have. For example, say you have a Scrambler with a full aftermarket exhaust and a new air filter. You can buy a Rexxer kit and have it sent to you with a specific map for your exact bike model and set up, and if your setup changes you can download a map online. Keep in mind these are general tunes, if you want to achieve the maximum potential of your mods you will have to get it dyno-tuned at a shop, which usually costs a significant amount more. In addition to tuning, a Rexxer unit will let you read and clear check engine light, reset maintenance light, reset TPS, adjust trimmer, and clear adaptive parameters. One of these kits will set you back about $600, but it’s well worth the investment.
What does a booster plug do?
A booster plug is a more budget friendly option at around $200. It fits in your bike’s air intake temperature sensor and tricks the ECU into thinking that the running temperatures are lower and adjusts the amount of fuel being fed to the engine. It automatically adjusts your bike to run richer (Fuel > Air) to even out the Air-Fuel. It balances the mixture, but there is nothing else up its sleeve.