12oClockLabs LLC
Calculate Using Your Gearing and/or Tire Size
If only using sprocket info, leave tire settings as default.
If only using tire info, leave sprocket settings as default.
Only the fields you change will be used in the calculations.
Circumference measurement of the tire is much more accurate than using a tire code.
You can use inches or mm for circumference, but both fields must be same unit of measure.
If you have a YXZ1000 GYTR Gear Reduction Kit with 30" wheels, click here for auto calculation.
  Front Sprocket Rear Sprocket Tire Circumference
Factory Specs:
Your Specs:
Factory Error: % WR250X/R is about 7.7%
Most sportbikes are about 5%
Use 0.0% if unsure

Calculate Using Your GPS
NOTE: You must perform a programming reset before each GPS comparison test drive.
GPS Reading:   Acceptable Inputs are MPH, KPH, Miles, or Kilometers.
Both input values must be the same unit of measure.
Tip: It's best to drive until your GPS reads 60mph or 100kpm, or
if using distance measurements travel at least 60 miles, or 100km.
Vehicle Reading:  

SpeedoDRD Version Type: (Look at white sticker on unit, example 3.62M is Version M)

Calculation Results
Please Select a SpeedoDRD Version.
Version info is at the top of the instruction book or on the back of the SpeedoDRD device.
Look for an M or an X after the version number. M is the newest verison, X is an older version.