When you already have a Exhaust (we hope you buy our Torque Hammer for the 1125) and Air filter for your Buell 1125R or 1125CR, and you only want too have a good running Bike, Buy this ECM with, our fuel and ignition map inside. I tested this ECM with all the big exhaust manufacturers, mounted on our test bike in our dyno room, before we released this product. It makes your bike run so smooth and strong. I made a new ignition and fuel map for this setup and tested it on more the 25 bikes now and more then 10 different exhaust manufactures. And I can only say, when you love your Buell take care of the Fuel. This product is a complete ECM reprogrammed for all 1125R and 1125CR models. Just change it with your original one, reset TPS by opening throttle 3 times, and go for it. You need to reset the TPS every time before you start the bike (You also need to do that with a stock ECM to prevent a bad running bike.