Speedometer calibration device By ksmason42 (Read 3,702 times)

[jct842]

Even if you could make a way to calibrate a chinese scooter that is going 40 to say 40, when it gets to 50 it will more than likely be off, they are not linear.

[Alleyoop]

I tried one of the Geared Bolt ons from UK they sell for mechanical and digtial speedos and IT was garbage took it off right away.
Alleyoop

[Deleted]

I just use a bike spedo and marked the accurate speed on the chinometer cover with a sharpie for night driving.

[jct842]

I just came back from riding 2 scooters with my replacement gps taped to my knee. a 150cc gy6 and a riva 180cc. The chinese dial is laid out non linear at the lower speeds and up to 25 is dead nuts on. from 30 on up is reads slow and at a true 55 it has to say 60 on the speedo. The jap speedo is layed out linear yet is high then low all the way up to 60 which reads a true 57.7. Conclusion no need to worry both are close enough that you would never get in trouble with the law. In all fairness the chinese one is more predictable and consistant in its error even though it has slightly more error at indicated 60. The jap one is slightly higher then lower when checked at 5 mph incrediments but at 60 true has less error there. THERE IS NO WAY POSSIBLE THAT A MECHANICAL DEVICE COULD INCREASE ACCURACY IN EITHER OF THESE TWO SCOOTERS/