The Harley-Davidson 1200 Sportster is frequently modified and customized with both Harley-Davidson original parts and aftermarket add-ons and accessories. The 1200 engine can be easily modified to produce more horsepower and torque. Kits are available from Harley-Davidson Screaming Eagle, Revolution Performance and Weisco. All kits involve essentially the same steps, and many bolt to the original cases with no modifications.
Things You'll Need
- Big-bore kit
- Basic standard tool kit
- Torque wrench
- Carburetor jets
- Air intake kit
- Exhaust kit
- Ignition module
Establish a game plan and purchase necessary parts. Determine what big-bore kit and heads you want to increase the horsepower on your Sportster. To accommodate these changes, you will also need to increase airflow by changing your air intake and exhaust system. You will need to rejet your carburetor also and use an aftermarket ignition module. These are available from several manufacturers. Also remove the stock rev limiter and ignition map designed by Harley-Davidson.
Remove the engine from the frame and remove the old heads, cylinders and pistons. Thoroughly clean all parts and set them aside.
Install new pistons, ensuring that piston pin clips are installed properly and pistons are facing the correct direction. (An arrow usually points to the intake side of the piston.) Using a piston ring compressor, install the new cylinders on the pistons, taking care not to damage the new piston rings.
Install the new heads. Using a torque wrench, ensure that all fasteners are torqued to proper specifications. Adjust valves to the specifications provided with the kit.
Place the engine back in the frame, tightening all fasteners with the torque wrench. Install the new exhaust kit and the ignition module.
Rejet the carburetor and install it on the bike. The kit instructions will often tell you what size jets are needed for the carburetor to function properly at your altitude. Install the new air intake kit.
Run the bike through the break-in procedure recommended by the kit manufacturer and have it dyno tested. Depending upon the kit you chose, the engine should be in the 100-115 hp range. If not, rejetting the carburetor using dyno analysis and reprogramming the aftermarket ignition module should provide the desired horsepower.
- Photo Credit I will be back shortly image by A. Leonardo from Fotolia.com
How to Increase the Horsepower of a Sportster
How to Increase the Horsepower of a 2007 Harley Sportster 1200; HD 1200 Sportster Performance; Print this article; Things You'll Need. Performance...
How to Get More Power Out of a Sportster 1200
How to Get 100 HP From a 1200 Sportster; How to Tell a 2000 Sportster 883 From a 1200; Comments You May...
Disadvantages of the Sportster 1200 Conversion
A 1200 cc big-bore kit is an engine upgrade. ... Increasing the horsepower of your Harley Sportster 1200 involves trade-offs between performance...
Harley-Davidson 1200 Engine Specs
How to Get 100 HP From a 1200 Sportster; Harley-Davidson Engine Specifications; 1997 Harley-Davidson Sportster 1200 Specs; Comments You May Also Like.
Sportster 1200 Specifications
2001 Harley-Davidson Sportster 1200 Specs. From its introduction in 1957, the Sportster has remained a best-seller for the Harley-Davidson Motor Company. For...
How Do I Convert Sportster 883 to 1200?
How to Install a Chrome Customizer Kit for a 2001 Sportster. There are a few dress up kits on the market, ......
Harley-Davidson Screamin Eagle Exhaust Tips
Harley-Davidson Screamin Eagle Exhaust Tips. Harley-Davidson is a leader in the industry when it comes to motorcycles. ... How to Install Harley...
Harley 883 Performance Technical Tips
Harley-Davidson Sportster 883 models produce 40 horsepower in stock factory condition. Several incremental modifications can be made to double the stock horsepower...
How Fast Is the 1200 Sportster?
How to Get 100 HP From a 1200 Sportster. How to Do an Oil Change on a Harley Davidson Sportster. How Fast...
1988 Harley Sportster 883 Specifications
The 1988 Harley-Davidson XLH Sportster 883 Standard was a classic bike equipped with a 48-horsepower engine, whereas the Harley-Davidson XLH Sportster 883...