14 Motorcycling Acronyms to Know

By Ricardo N Feliciano ·

The military is notorious for its use of acronyms. As a Navy veteran, I’ve met plenty of sailors and soldiers who have used the acronyms for so long that they no longer remember what they stood for. I have a hunch that there’s many of us in the motorcycle community that are in the same boat.

Whether you’re a seasoned motorcyclist who forgot what the term stood for or you’re newer to bikes and would like to learn some definitions, here’s 14 motorcycling acronyms to know.

  1. HP - HorsePower - this is a frequently misunderstood unit of power. Motorcycles are typically compared in terms of their horsepower however this isn’t always apples to apples comparison. In the United States we use hp (imperial) while in Europe they use hp (metric), which is 98.6% of the former unit. To add to the confusion, not everyone measures horsepower at the same location which effects the measurement. The most popular location measured by everyday riders is via the back wheel. Another popular location is at the engine crank, which is called brake horsepower.

  2. bHP - Brake Horsepower - is a measurement of horsepower (HP) taken at the engine crank. This gives a higher number then when taken at the wheels since it doesn’t take into account power loss from the drivetrain.

  3. RPM - Revolutions Per Minute - is the measurement of speed for something that goes in a circle. In motorcycles this speed can be at the wheels but is typically used for the engine crankshaft. Since engines are designed with specific RPM ranges in mind, the lower end of the range indicates the speed needed to keep the engine from stalling while the higher end of the range indicates the maximum speed the engine can safely run.

  4. ATGATT - All The Gear, All The Time - a philosophy that many riders live by in order to stay safe. While how strict a rider adheres to this will vary, in general it means to always wear all the safety gear you have without excuses. The typical excuses being, it’s a really hot day or, I’m just going down to the gas station.

  5. ECU - Engine Control Unit, Electronic Control Unit - this is a computer system on modern bikes. For an engine, this is the brains of the bike and controls aspects such as when and how much fuel to inject.

  6. ABS - Anti-lock Braking System - a system that uses speed sensors on a wheel to determine when it has or is about to lock up, and releases the wheel. This system helps prevent crashes when a wheel loses grip, especially when the road is wet. A motorcycle may have ABS installed on both or just one wheel.

  7. CC/CI - Cubic Centimeters, Cubic Inches - the volume of air an engine can displace (or pump) in its cylinders. This is the most direct way to compare engines of similar class in terms of power. CCs are used by non-American brands and CIs are used for most models of American brands. 1 cubic inch is about 16.387 cubic centimeters.

  8. DOHC - Dual OverHead Camshafts - a design aspect of some engines. This means the camshafts (two) are above the engine where they can more efficiently operate the opening and closing of valves.

  9. SFF - Separate Function Forks - instead of both forks doing the exact same job and being virtually identical, the functions are split. One fork has the spring and the other deals with damping.

  10. RSU - Rear Suspension Unit - all of the components that make up the rear suspension. This includes traditional mechanical components such as shocks and the swingarm as well as electrical ones on more modern bikes.

  11. TFT - Thin-Film Transistor - a technology used to make screens. Competing technologies are LCD, OLED, and E Ink to name a few. When TFT is mentioned in motorcycling, it’s typically used in the context of a superior screen for the dash.

  12. MSRP - Manufacturer Suggested Retail Price - this is the price a manufacturer such as Harley-Davidson or Honda suggest to their dealers to sell a particular motorcycle. This is rarely the actual price you will pay. Fees, taxes, discounts, etc can and usually do come into play.

  13. OTD - Out The Door pricing - unlike the MSRP, this is what you ultimately pay for a motorcycle in order to take it home. When shopping for a motorcycle, ask the dealer for the OTD price. This is the best way to know which bike is the better deal as MSRP and fees can be manipulated to cover up the true cost of a bike.

  14. TCS - Traction Control System - a combination of components designed to keep a motorcycle upright with both wheels on the ground. In its simplest form TCS can be just ABS however modern bikes have included newer systems. This can be lean sensors, wheelie control, etc and a computer to run these systems.

I hope these acronyms, what they stand for, and their definitions were helpful. Stay tuned for more terms in future blog posts.