Caution – S&S Cycle Speedometer Calibrator (Part 55-1007) User Manual

Page 2

The S&S

Speedometer Calibrator allows owners of Harley-

Davidson

and Buell

motorcycles equipped with stock electronic

speedometers (those with LCD mileage displays) to correct
inaccurate speedometer and odometer readings. Typically, these
are caused by the installation of different transmission or wheel
sprockets, early stock or aftermarket transmission gears, or rear
tires with a diameter other than stock.

The S&S Speedometer Calibrator allows the rider to correct
Harley-Davidson

electronic speedometers easily and without

special tools or expensive test equipment. Adjustments can be
made between -29% and +69% in 1% increments.

The calibrator’s small size permits convenient mounting, and
sensitive components are sealed for protection against weather
and vibration.

To prevent possible damage to motorcycle electrical system,
disconnect battery ground lead (“-”) from motorcycle frame
prior to installing calibrator.

Installation

Place pressure on release clips and unplug wiring connector
between speedometer and transmission sensor. Connector is
usually located under seat. See Picture 1.

Attach male and female ends of connector to respective
ends of S&S Speedometer Calibrator and secure calibrator
and wires to motorcycle. See Picture 2. Route wires to avoid
stretching, pinching, and chafing against frame. Reconnect
battery ground lead to frame.

NOTE - Calibrator features screw-eyes, but can be mounted with
wire-ties if desired.

Improperly routed wires may wear and short against frame,
causing extensive damage to motorcycle electrical system and
possible fire hazard.

Initial setting of adjustment screws should be “0” position.
See Picture 3.

NOTE - Slot in each screw has small notch in one end. Notched
end must point toward selected number. Screws can be rotated
full 360 without damage.

Determine Calibration Percentage

Determine amount of speedometer error. Most common
methods are to compare speedometer reading to
speedometer known to be accurate, or compare odometer
reading (mileage) to measured distance. Highway markers
are usually accurate, but readings from several different
markers should be taken and compared for confirmation.
Radar can also be used to determine actual speed. In case of
gear change, number of teeth on original and replacement
sprockets can also be used to determine percentage of
speedometer error. Note that formulae for transmission and
wheel sprockets are different.

Calculate percentage of speedometer error using one of
following formulas:

Actual Speed (or mileage) - Indicated Speed (or mileage)

Indicated Speed (or mileage)

OR:

# of teeth on new trans. sprocket - # of teeth on original sprocket

# of teeth on original trans. sprocket

OR:

# of teeth on original wheel sprocket - # of teeth on new sprocket

# of teeth on original wheel sprocket

CAUTION

Picture 1

Picture 2