It would be difficult to ride a motorcycle if the speedometer stopped working. You may cross the maximum allowed limit in a lane, which can lead to a penalty. When I was riding my Royal Enfield Classic 350, the speedometer stopped working. It was a very difficult motorcycle ride with a faulty speedometer.
So, what causes a motorcycle speedometer to stop working? A broken speedometer cable, a faulty speedometer gearbox hub drive, broken wiring, and a faulty sensor are why a motorcycle speedometer stops working or gives inaccurate readings. Replace the speedometer cable and change the box hub drive to solve the problem.
Table of Contents
- 1 How Does Analog Speedometer Work On A Motorcycle?
- 2 How Does Digital Speedometer Work On Motorcycle?
- 3 How To Fix Motorcycle Speedometer Not Working?
- 4 How Do I Know If My Motorcycle Speedometer Cable Is Bad?
- 5 Can A Motorcycle Speedometer Be Calibrated?
- 6 How Do You Fix An Inaccurate Speedometer?
- 7 How Much Does It Cost To Calibrate A Motorcycle Speedometer?
- 8 Conclusion
How Does Analog Speedometer Work On A Motorcycle?
A typical mechanical speedometer on a motorcycle is not a complex piece of equipment, and its working is very simple.
It consists of an analog speedometer gauge and a cable typically connected to the motorcycle’s front wheel.
A magnet is attached to the other end of the speedometer cable. When the front wheel rotates, the magnet attached to the other end of the speedometer cable also rotates. Due to the rotation of the magnet, the magnetic field also rotates the aluminum speed cup, which deflects the hairspring, and the speedometer needle shows the motorcycle’s speed.
How Does Digital Speedometer Work On Motorcycle?
A digital speedometer is a complex piece of equipment that shows the motorcycle’s speed more precisely. Generally, the digital speedometer comes in expensive superbikes.
In a digital speedometer, a sensor is installed near the transmission gear. The teeth of the gear trigger the sensor, which sends a square-wave signal to ECU, which further calculates the motorcycle’s speed due to a change in frequency.
How To Fix Motorcycle Speedometer Not Working?
My Royal Enfield Classic 350 has a mechanical speedometer that stopped working while highway-riding. Fortunately, I discovered that my speedometer cable was broken. Due to a bad cable, the motorcycle speedometer stopped working. So, I replaced the cable, and my speedometer came to life.
There could be several more reasons why your motorcycle speedometer isn’t working. We shall find out all possible causes and try to repair them.
Let’s start the repair…
1. Arrange All Required Tools
You should have all the necessary equipment ready before repairing any motorcycle speedometer. You may need to remove the speedometer cable, front-wheel gearbox hub, and speedometer gauge to rectify the issue.
Get the following things ready before starting the speedometer repair:
- Matric wrench set.
- Power drill.
- Microfiber towel.
2. Replace The Speedometer Cable
The functioning of a mechanical (analog) speedometer is pretty straightforward. A cable is attached to the front wheel that revolves when the motorcycle moves.
The rotation speed depends on how fast your motorcycle’s front wheel moves. This cable rotates the aluminum speed cup in the speedometer gauge, which moves the needle and indicates the motorcycle’s speed.
If the speedometer cable breaks or gets worn, it won’t rotate the aluminum speed cup. As a result, the speed reading needle doesn’t move.
A faulty speedometer cable is the most common reason your motorcycle speedometer doesn’t work. So, first, remove the speedometer cable from the front wheel hub and rotate it with the help of a power drill.
If your speedometer gauge doesn’t show any reading and the odometer reading doesn’t move, it means the cable is faulty and needs to be replaced. You can buy an aftermarket speedometer cable for your bike model and replace it yourself.
In my case, the speedometer cable was the culprit, and I replaced the cable myself. You need to loosen some nuts, and the speedometer cable will come out. Install the new cable similarly, and your speedometer will start functioning.
3. Replace The Speedometer Box Drive Assembly
A speedometer box drive assembly is attached to the motorcycle’s front wheel. This box drive is coupled with the front wheel with small gears. When the motorcycle moves, the front wheel rotates this box drive and the speedometer cable.
But, sometimes, the speedometer box drive assembly gets damaged due to wear and tear. As a result, your speedometer cable doesn’t rotate, and the speedometer stops working.
You can replace the speedometer box drive assembly at home. Just unscrew the front wheel nuts and take the bolt out.
Remove the defective speedometer box drive assembly and install the new one. Tighten all the nuts and restore the front wheel to its original condition.
Your motorcycle speedometer will start working again. If it doesn’t work, it means there is some major fault with the speedometer gauge, and you should replace it.
4. Replace The Speedometer Guage
If you have tried all the above fixes, but your speedometer is still not working, it means your speedometer gauge is faulty.
You can buy an OEM speedometer gauge for your motorcycle model and replace it yourself or get it done by a professional mechanic.
The gauge must have some faults if your speedometer needle moves freely or shows inaccurate readings. I found a great video tutorial on repairing the faulty speedometer gauge.
How Do I Know If My Motorcycle Speedometer Cable Is Bad?
If your speedometer needle is waving or not moving, it means your speedometer cable is damaged, and you should replace it.
You can also remove the cable from the motorcycle’s front wheel and inspect the shape of the cable.
If the cable has gone ‘round‘ instead of ‘square-ish,’ it means it has gone bad due to wear and needs to be replaced.
Can A Motorcycle Speedometer Be Calibrated?
A motorcycle with a mechanical speedometer can not be calibrated, but a digital speedometer can be.
The digital speedometer uses a speed sensor triggered by the transmission gear’s teeth and sends square-wave signals to the ECU. Your ECU further processes the signal frequency and calculates the speed.
How Do You Fix An Inaccurate Speedometer?
You cannot calibrate the inaccurate speedometer at home. You need to visit the nearest motorcycle dealer or an ASE-certified mechanic garage to re-flash the ECU. They will calibrate your motorcycle’s digital speedometer.
How Much Does It Cost To Calibrate A Motorcycle Speedometer?
A motorcycle’s digital speedometer can be calibrated at the nearest dealer shop or a mechanic garage. The speedometer recalibration costs anywhere between $50 to $100. The cost will depend upon the location and motorcycle model.
A faulty speedo cable is the most common reason your motorcycle speedometer is not working. You can replace the cable yourself or visit a mechanical garage to get it replaced.
But, sometimes, issues could also be with the sensor and speedometer gauge. So, follow the above troubleshooting guide to fix the issue.