1. Here's the Rocker ready...
1. Here's the Rocker ready to attack the streets with the Swept Speedsters installed.
Recently we had the pleasure of installing a new exhaust system from Cobra Engineering on a '08 Rocker C model. Cobra manufactures both metric and American motorcycle parts, and is located in Yorba Linda, California. The company recently released the Swept Speedsters exhaust system ($689.95) for Softail models. It's essentially a 2-into-1 system that looks like a 2-into-2 but it's been outfitted with a Power Port that connects the pipes to increase horsepower and torque numbers. So with the power and performance of a 2-into-1, you get the style and aesthetics of running a 2-into-2 system.
To go with the new pipes, Cobra also manufacturers a fuel management system called the Fi2000R O2 ($279.95) that is a plug-and-play unit for closed-loop EFI Harleys. The Fi2000R O2 comes preset and essentially works just like a jet kit on a carburetor. Depending if your bike is bone stock or you've added a high-flow air filter kit and pipes, you can make adjustments to the three pots to adjust idle, cruise fuel, and full throttle applications. Best of all, you don't have to plug anything into your computer to download programs or maps. It plugs right into your oxygen sensors and fuel injectors.
A K&N RK Series high-flow air cleaner kit ($215.95) was used for this project. This assembly was developed for Softail and Twin Cam models and was built around the iconic K&N high-flow air filter. The RK Series assembly includes a black powdercoated billet aluminum backing plate that eliminates external breathers and features a built-in, velocity stack. The result is an increase in airflow to the engine without sacrificing filtration. Best of all, the RK Series kit fits inside your stock air cleaner cover.
Installation was a snap and one could easily complete everything in his or her garage in no time at all. You only need the basic tools and some good music in the background.
 2. The Swept Speedsters come...  2. The Swept Speedsters come with head pipes, mufflers, chrome heat shields (shown here with heat shields mounted), mounting bracket, and mounting hardware. The Fi2000R O2 fuel management system is a 49-state legal fuel management system. California residents will need the Fi2000R ARB model. Also available is a passenger peg relocation bracket ($29.95) that mounts underneath the new pipes. |  3. This K&N RK Series assembly...  3. This K&N RK Series assembly includes a new backing plate, velocity stack, high-flow air filter assembly, and all necessary mounting hardware. |  4. We got started by removing...  4. We got started by removing the stock exhaust system. First, we unbolted the nuts from the exhaust studs, and then unplugged the O2 sensors from the stock pipes. After the stock pipes were removed, we took the O2 sensors from the stock pipes and installed them on the Swept Speedsters. |
 5. But before mounting the...  5. But before mounting the new exhaust, we had to install the mounting bracket to where the swingarm meets the bottom of the frame (arrow). |  6. Once we installed new...  6. Once we installed new exhaust gaskets, and the mounted the stock flanges and retaining clips to the new pipes, we tightened them at the heads and also at the new mounting bracket. Then we slid the new mufflers onto the headers and tightened them down. Here is where the Power Port is located (arrow). |  7. Then we installed the...  7. Then we installed the chrome heat shields and tightened up the heat shield clamps. |
 8. The Fi2000R O2 mounts...  8. The Fi2000R O2 mounts under the seat, next to the battery and plugs right into your stock fuel injectors. First, we disconnected the battery cables, propped up the rear of the tank, routed the Fi2000 wiring to the injectors and plugged the new male connectors into the stock female connectors of the fuel injectors. |  9. Then we routed and plugged...  9. Then we routed and plugged in the Fi2000R O2 sensors to the stock plugs located in the front (arrow) near the voltage regulator), and also in the rear (located next to the oil bag). |  10. Once the Fi2000R was...  10. Once the Fi2000R was hooked up, we moved onto installing the new air cleaner assembly. We removed the entire stock air cleaner assembly. Then, we built the backing plate of the K&N assembly by attaching the new velocity stack from the rear with the provided gasket and hardware. Next, we bolted the new assembly with the provided breather bolt extensions and stock bolts to the heads. |
 11. The new air filter assembly...  11. The new air filter assembly was attached to the new unit and the stock air cleaner cover was reinstalled. The install was complete at this time. |  12. Here's the Rocker with...  12. Here's the Rocker with the Swept Speedsters, Fi2000R O2, and K&N RK Series kit installed, waiting for some passes on the dyno. |  13. Dynojet Research The...  13. Dynojet Research
The stock Rocker C produced a baseline run of 57.92 hp and 75.42 lb-ft of torque. Once all of the components were bolted on, the numbers jumped to 67.53 hp and 80.91 lb-ft of torque. That's an increase of 9.62 hp and 5.49 lb-ft of torque. After we put a few miles on the bike, we'll play with adjustments on the Fi2000R O2 and we bet we'll see even more increases! |