RPM Sensor · In production · Pre-order

MicroDyno-RPM
RPM off the coil

A tiny Bluetooth module that reads every ignition edge straight off the coil and streams it to the Microdyno app. The app derives true, instantaneous RPM — no microphone, no audio tuning, no guesswork.

incl. VAT · +shipping · ships in ~14 days
MicroDyno-RPMLive · BLE
8 240
RPM
<1 ms
Edge resolution
0–50k
RPM range
BLE 5.0
Wireless
~12 g
Weight

From spark to screen

The sensor taps the ignition pickup, cleans every pulse with an opto-isolated front-end, and streams the raw edge timing over Bluetooth. All the maths happens in the app.

01

Clip to the coil

Connect the input to the ignition/AC pickup. A PC817 opto front-end with TVS protection turns each spark into one clean digital edge.

02

Stream every edge

The ESP32-C3 timestamps each edge to the microsecond and pushes the raw stream over BLE — no averaging, no information lost.

03

Read true RPM

The Microdyno app turns the edges into instantaneous RPM and a full power curve — pick your pulses-per-rev and go.

Connect after the voltage regulator. Tap the regulated 12 V AC output only — never a raw, unregulated winding, whose voltage can climb past the input's safe range at high RPM.

Ground-truth, not guesswork

Edge-accurate

Reads the ignition directly, so RPM is exact even at idle or 15,000 rpm — no microphone tuning, no harmonic hunting.

Wireless & instant

Pairs with the app over Bluetooth 5.0 — no cables, no setup screens. Open the app, it connects, live RPM appears.

Over-the-air updates

New firmware installs straight from the app over Bluetooth — self-healing, checksum-verified, never a cable needed.

All-day battery

Runs off a small LiPo, sleeps between sessions and wakes itself on the first engine pulse — or a tap of the button.

Fits any engine

Set 1–24 pulses per rev in the app for VAPE, CDI, points or AC pickups. Single, twin, multi — it just works.

Tough & tiny

~12 g with an opto-isolated, TVS-protected input that shrugs off ignition noise and keeps the sensor safe.

The details

Measurement
Ignition-edge timing, µs resolution
RPM range
0 – 50,000 rpm
Pulses / rev
1 – 24, set in the app
Front-end
PC817 opto-isolator + TVS protection
Wireless
Bluetooth 5.0 LE (ESP32-C3)
Firmware
Over-the-air updates from the app
Power
LiPo, USB-C charge, deep-sleep + wake-on-pulse
Weight
~12 g
App
Microdyno for iOS & Android

Get the MicroDyno-RPM

In production now — reserve yours with a pre-order and it ships as soon as your batch is built.

€49
incl. VAT · +shipping · ships in ~14 days
Pre-order now