Making tachometers and speedometers

**tonyfoale** · May 21, 2023, 02:50 PM

Originally Posted by th62

........ I've bought a magnetic sensor speedo so I don't have a great heavy cable running down beside the fork.

I have just checked the schematic for my tacho and a speedo will be much easier to wire up. Most of the components in the tacho are for conditioning the noisy signals from the ignition system and you will not need that circuitry. A magnetic or optical wheel sensor will feed directly into the Arduino which feeds directly into the stepper.

Please post a link to the speedo that you bought so that I can check out that the sensor is suitable. Also how do you plan on triggering the sensor? You may be able to do that off the bolts that hold the disc, unless they are non-magnetic stainless. You will get a smoother display with multiple pulses per wheel revolution. It is only a setting in the software to accommodate any number of pulses and the maximum speed that you want to display.

**Saltfever** · May 21, 2023, 07:32 PM

Oh my goodness, this sounds very interesting! I have been looking for an excuse to learn Arduino-ese for the past few years. Was even thinking about learning Python from my grandson to see if I could do sumptin useful. And, now Tony, of all things, you have cast away ESP32 tech to tempt us with the Arduino world!

So here is my problem. It is quite difficult to get good resolution on a high revving engine when all the tick marks are crammed into a 270-300 degree clock face. For example, if a shift point is around 9,500-10,000 rpm, usually everything (in my application) below 6,000-7,000 rpm is useless noise. I would love to display only the top 2,500-3,000 rpm in that same 300 degree window with the correspondly wider tick marks giving much better resolution. My apologies to our motorcycle friends for inferring that 10k rpm was a high number.

Also, Tony, this tacho thread may take on a new life. Maybe its own thread would be suitable? And, THAN YOU for your always creative and interesting ideas.

**tonyfoale** · May 22, 2023, 02:38 AM

Originally Posted by Saltfever

.... And, now Tony, of all things, you have cast away ESP32 tech to tempt us with the Arduino world!

I used the Arduino Nano in this project because they are small and I had some. Also it is a task that the Arduino can handle with ease. Any new projects will probably be done with an ESP32, an Arduino on steroids.

Originally Posted by Saltfever

So here is my problem. It is quite difficult to get good resolution on a high revving engine when all the tick marks are crammed into a 270-300 degree clock face. For example, if a shift point is around 9,500-10,000 rpm, usually everything (in my application) below 6,000-7,000 rpm is useless noise. I would love to display only the top 2,500-3,000 rpm in that same 300 degree window with the correspondly wider tick marks giving much better resolution. My apologies to our motorcycle friends for inferring that 10k rpm was a high number.

Easy-peasy.

Originally Posted by Saltfever

Also, Tony, this tacho thread may take on a new life. Maybe its own thread would be suitable? And, THAN YOU for your always creative and interesting ideas.

th62 I do not want to hi-jack your bike building thread so would you prefer that I move any additional content to a new thread or keep it here? It is your call.