Rainbows - oil on the street
Rainbows in the Mountains - When angry locals in the mountains put diesel fuel in the corners in an effort to stop sports bikes street fighting.
Raised Tranny - Harley bikers would use a spacer to raise the transmission on their bikes so when riding in dirt and mud to try to keep the primary cover away from anything that might knock into it.
Rake - Rake, measured in degrees, describes the angle of the front fork or the steering axis from the horizontal or vertical plane.
Rat Bike - Bike made from several machines and kept on the road using as cheap as possible and painted matt black. Now has a class of its own and defined as any thing Mad Max would shoot at.
Rat Bike (#2) - A cosmetically challenged bike. It can be anything from a 'no maintenance' bike to a fine running 'sleeper'.
Rat Bike (#3) - The bike you use in foul weather or when you are going into a questionable neighborhood. A cheap reliable bike, but if lost or stolen is no big deal. This bike never gets washed.
Rebound - Rebound defines the return stroke of the suspension.
Reduced effect - In some countries certain motorcycle models are sold with less horse power to comply with legal or insurance regulations in that country. For instance, a country might allow 16-year-olds to drive 125 cc bikes with no more than 15 hp. The bike would then have to be modified to output no more than 15 hp. In another example insurance companies may not want to insure bikes with more than 100 hp, or may increase insurance rates for these bikes to the extent that most people would want to buy a reduced-effect version of their bike instead.
Revolutions per minute (or REV) - The number of revolutions the engine makes in a minute. Abbreviated RPM and often referred to as "rev".
Revolution - The Revolution engine, Harley-Davidson's first water-cooled engine (V-Twin, produced from 2002 - Current Day)
Rice Burner - Slang term for a Japanese made motorcycle.
Rice Rocket - Japanese Sport Bike
Ride Captain - The leader of a group Ride.
Ride Lieutenant - The last (and most experienced) rider in a group ride.
Rigid or Rigid Frame - A type of frame that has no swingarm, it is a one piece neck to rear axle frame.
Rippin' it Up - (1):When a biker pulls away hard and fast from a stand-still and leaves behind a patch/line of rubber (2): A term used to describe generally fast, skillful and/or aggressive riding.
Road Agent - Another term for Highway Patrol Officer or State Trooper.
Road Gator - 18-wheel Tire Pieces
Road Rash - A Wipeout that scrapes off some of your skin. Marks left behind on a biker's body after falling down while moving.
Roadie - Yamaha Road Star
Rocker - Part of M/C Colors usually designating geographic location. The curved patches of a club's patch, typically denotes the club name or chapter on one and resident town or city on the other.
Rocker-Clutch or Rocker Clutch Pedal - This term was used to describe the foot clutch pedal's that rocked back and forth on a central pivot point hence the term Rocker-Clutch) and the rider would step on the front toe section to disengage the clutch and the rear section with the heal of your boot to engage the clutch.
Rolling Basket - Basket case bike, fairly intact but does not run, needs work
Rolling Chassis - Incomplete project, has everything but mill & tranny
Roost - The spray of dirt off the rear wheel of a motocross motorcycle
Roun To-It - Instrument used to delay a job, as in " one of these days I'll get around to it".
RUB - Rich Urban Biker. A term usually used by real Harley Bikers to describe the weekend wannabe accountant types who buy a Harley ''cause they can and the status of it, but couldn't tell a camshaft from a brake pad. Bikers that ride with more money than knowledge, experience, and ""street savvy"".
Rubber - Tires, tyres
Rubberside - Towards the bottom of the bike, or bottom area of a part or component
Run - Riding for a particular function or purpose