- Joined
- Mar 9, 2008
- Messages
- 2,595
- Reaction score
- 129
- Points
- 63
- Location
- San Jose, California (GMT -8)
A couple of weeks ago, I changed my front sprocket to 15T. I know this leads to speedo and odo error, and until I get a speedohealer, I wanted to know mentally what the speedo error was. Here's the setup I used:
First, tape a friend's GPS to your instrument panel. To get the tape behind the instruments, you have to remove your inner fairing (easy and takes 10 min). Be sure to use a friend's GPS! How crappy would you feel if your own GPS fell off and got ruined?
Next, place a video camera on a tank mount to video the whole instrument panel. Make sure the GPS, speedometer, and tachometer are all clearly visible in the field of view.
Go for a ride and video what the instruments are doing. Be sure to level your speed at approximately 10mph increments, and hold for several seconds. The instruments (GPS and speedometer) don't refresh instantly, and holding speeds allows the instruments to catch up.
Watch the video when you get home and input actual versus displayed speed in a spreadsheet. Plot actual speed versus displayed speed to get an idea of the error.
I will post my offset after I collect it tomorrow.
First, tape a friend's GPS to your instrument panel. To get the tape behind the instruments, you have to remove your inner fairing (easy and takes 10 min). Be sure to use a friend's GPS! How crappy would you feel if your own GPS fell off and got ruined?
Next, place a video camera on a tank mount to video the whole instrument panel. Make sure the GPS, speedometer, and tachometer are all clearly visible in the field of view.
Go for a ride and video what the instruments are doing. Be sure to level your speed at approximately 10mph increments, and hold for several seconds. The instruments (GPS and speedometer) don't refresh instantly, and holding speeds allows the instruments to catch up.
Watch the video when you get home and input actual versus displayed speed in a spreadsheet. Plot actual speed versus displayed speed to get an idea of the error.
I will post my offset after I collect it tomorrow.