Making your Harley-Davidson Ultra Classic go faster can be accomplished in progressive stages.
You can make a Harley-Davidson Ultra Classic go faster in a number of ways. The Harley-Davidson community divides these modifications to add power and make the Ultra Classic go faster into stages. Each stage makes progressive improvements in performance that will make the Ultra Classic go faster. One doesn’t need to all the stages to make the Ultra Classic go faster but one cannot, for example, complete a Stage 3 modification without completing Stages 1 and 2 first.
1. Improve fuel efficiency. The factory settings of the Ultra Classic are purposely not tuned for the bikes most efficient and powerful settings. This is done in order to comply with emissions controls and keep production costs down. A Stage 1 modification includes a new aftermarket exhaust system, a larger air filter and changes to your air to fuel ratio to burn fuel more efficiently. The purpose of a Stage 1 modification is to improve the flow of fuel through the system.
Fuel mixture is determined by your electronic control unit (ECU). Once the new performance exhaust and air filter is installed, the motorcycle fuel mixture must be adjusted. If the fuel mixture is too lean, fuel will be wasted and damage to the Ultra Classic could occur. If the fuel mixture is too weak, the motorcycle won’t run smoothly. To remap that fuel mixture and get optimum power, another electronic unit will need to be plugged into the ECU. The new until will control fuel flow into the system. There are a number of units on the market that plug into a factory ECU. Some only manage the fuel system while others can do much more and would be necessary for stage 2 modifications and above.
Once installed, map out and adjust your fuel system for optimum efficiency either through settings provided by the electronic unit’s manufacturer or at a shop with a dynamometer.
2. Complete a Stage 2 modification. Stage 1 might not give the Ultra Classic the power to reach the speeds desired. If so, complete the next stage of modifications. Stage 2 modifications can be done by a Harley-Davidson certified mechanic or done by someone with the requisite skills and knowledge of motorcycle engines.
Stage 1 improves the flow of fuel while Stage 2 is about keeping the valves that let fuel into your engine open longer and thus burning more fuel for more horsepower. In order to increase the flow into the engines, new cams are installed. Once installed, the Ultra-Classic fuel system will need to be re-mapped in order to ensure that power and efficiency is maximized.
3. Complete a Stage 3 modification. Stage 3 will also require an experienced motorcycle mechanic. Stages 1 and 2 must already be complete. While Stage 1 and 2 helped to more efficiently put more fuel through your engine and exhaust system, Stage 3 involves swapping piston heads in the engine to allow greater compression. Greater compression means more power. More power translates into a faster Ultra Classic. Stage 3 will offer about 25 to 30 more horsepower compared to a standard Ultra Classic engine with out any modifications.
4. Complete Stage 4. A Stage 4 modification is essentially turning the Harley-Davidson Ultra Classic into a racing bike. Just about anything that can be done to improve the performance will be done.
Stage 4 modifications will be more expensive and there will really be very little of that factory Harley-Davidson Ultra Classic left. Examples of changes might be a new transmission to make the Ultra Classic go faster and a stiffer suspension. One can bore out the compression chambers in the engine to make them larger. This of course would mean new, larger piston heads. Larger ports, stronger valve springs, larger valves and larger valve ports will all help improve engine power and make the Ultra Classic go faster. But be forewarned, these changes may also make the motorcycle run poorly in lower gears – making it difficult for street use, because the Ultra Classic will no longer want to go slow.