RPM meter with OLED and Motor

Hello Guys.
I would like create a litle project with arduino.

I have a motorbike which have a mechanical speedometer ( I mean RPM meter from 0-8000 rpm/min ).

But his mechanical part was destroyed and cant possible to repair it…

I have idea… Use Arduino Nano for create a RPM meter…

RPM meter have average 80 mm and height 100mm.

I would like use OLED dislay for show a digital data: RPM meter and Voltage meter and MiniMotor for move original pointer ( scale is 270° 0-8000 rpm/min )

Motorbike have 12V Acumulator and Generator 14V DC, ( for supply arduino i would like use 7809 because sometimes the baterry have 11,5V )

I have Electronic ignition ( Engine is 2-stroke 2-cylinder = 1pulse/1 rpm )

Ignition signal from sensor is +/- 1V . ( see attachment )

Digital data is not problem, but i dont have any idea how can i controll minimotor for control pointer ( correct data )

Have anybody any idea ?
Many thanks



Plenty of circuits etc around for the digital tacho idea.

I'd be cautious about using the Oled display as they can be rather fragile and easily end up with a cracked screen. Care would need to be taken relating to just how it was mounted as motorcycles tend to have a lot of vibration.

For the operation of the original needle, I once used a small servo which was geared up to the needle so that 60 degrees( or slightly less) made the needle move 270 degrees.
This was done with a relatively simple code via a picaxe but I'd imagine even easier with Arduino via mapping.

Ignition signal from sensor is +/- 1V . ( see attachment )

Is that an actual oscilloscope trace you have taken? It looks suspiciously clean to me, like it's an idealised drawing of what the output should be, not an actual measurement of what it really is. Ignition systems generally produce a lot of electrical noise, which you have to be careful with if you don't want fried electronics.

bluejets: I know.. many circuits but not lot :smiley:

PerryBebbington: Thats not my measuremment, but i Used this picture from another website, where solving some problem with the ignition. ( same ignition )

But if i have a space in to the original box from tacho, why not.

I know OLED is a very rather fragile, i know.. My vision is save this OLED display on a elastic board.

But OLED is only my idea ( could be a another type, but i would like use OLED )
Originaly first idea, was be use four 7 segments display for showing RPM ( retro style ), but this idea still stayed in the game.
But If i wanted create a new project, where i have a many posibility, i would like use these possibility for show another data..

  • actually voltage. ( arduino sensor )
  • actually current. ( arduino sensor )
  • actually temp.( ds18b20)
  • motor temp. ( ds18b20)

When i think about it, i have small space for all it :smiley:

One button for change screens ? that is a possible solutions or no?