AC-CDI v10


  • Programmable AC-CDI
  • For ONE or TWO* cylinders
  • For [2 strokes engines] and for [4 strokes engines with wasted spark*] * On 4stk engines with 1 pickup on the crankshaft, one spark occur at compression stroke and one at exhaust stroke. Firing in the exhaust stroke is a wasted spark. Hence the name…
  • Microprocessor control unit
  • Easy programming with USB connection and terminal console
  • Compatible Windows, Linux, Mac
  • One programmable ignition curve
  • Rev from 10 to 20,000 RPM
  • Adjustable timing in 13 steps from 500 to 20,000RPM
  • Soft rev limiter.
  • 1 input for a inductive pickup (VR)
  • Automatic detection for pickup polarity
  • 1 output for a capacitive coil type
  • Non volatile configuration
  • Kill switch
  • Power supply voltage DC 10 to 16 volts
  • Current drain: 100mA
  • Protected against reverse supply voltage
  • Dimensions: 100 x 60 x 25mm (3.9 x 2.4 x 1inch)
  • Plastic box
  • Wires soldered, no connector provided
  • Made in France
  • Only available in the SHOP section
  • Source and hardware not available


If there is one separate pickup:
=> This AC-CDI works.
If there are 2 separate pickups (one for low RPM and one for High RPM):
=> This AC-CDI works.
If there is no separate pickup and the timing is done by using the High Voltage of the stator:
=> This AC-CDI will NOT works
If the engine works with Missing Teeth:
=> This AC-CDI will NOT works

* Twin-cylinders at 360° crankshaft angle:
The engine works with WASTED spark.
If there is ONE twin coil:
=> This AC-CDI works.

See: CDI compatibility

Remember that ignition coils are different from TCI to CDI system
– CDI coils have low inductance and impedance around 0.5-0.8ohm
– TCI coils have higher inductance and impedance around 1-3ohm

Remember there are AC-CDI and DC-CDI…


– 1 input for inductive pickup with 1 signal per crank rev.
– Pickup must puts out 3 to 30Vac
Points, reluctors, Hall sensor, optical sensors can be used as long as they give only 1 pulse per revolution.
– This CDI is not compatible with multi-pulses pickup or missing tooth wheel.

Rev Limiter:

The last RPM value you enter is the “rev limit” that stop all sparks.

Ignition timing

Draw the ignition timing in this XLS sheet.

Terminal console

Click here for more info
CoolTerm for Win/Mac/Linux
Teraterm, Putty, Kitty for Win
– Console commands for Mac:
ls /dev/*usbserial*
screen /dev/cn.usbserial-xxxxxxxx 115200 -L
screen /dev/tty.usbserial-xxxxxxxx 115200

– Console commands for Linux:
3 ways to find the COM-port:
tail -f /var/log/syslog | grep USB
dmesg | egrep --color 'serial|ttyS'
ls /dev/ttyUSB*

Config port:
sudo su
stty -a </dev/ttyUSB0
stty -F /dev/ttyUSB0 cs8 115200 time 10

cat /dev/ttyUSB0 & cat > /dev/ttyUSB0

HowTo setup

Setup ACCDIv10r0.pdf



Click here for more info



Connection to the box:

Setup a ignition timing:

Change the ignition timing:


Click here for more info

  • Version v10r0c0:

    • First Version.
    • 5 seconds temporization to detect console.
    • Wires come out at 90degrees.
    • LED on the length side.

  • Version v10r1c0:

    • Automatic detection of the console.
    • Wires come out at 180degrees.

7 thoughts on “AC-CDI v10”

      1. I’ll be very interested in how it works out on the xt200. I have 2 of them I’m rebuilding and have been looking for a good cdi solution. Thank you so much for all of this.

    1. Hi Mark,
      Beware ! AC-CDI v10r0c0 dont use Wifi but use direct USB connection for setup.
      The 2 last prototypes are available now in the Shop and I going to order some new PCB for the modification I had to make. (AC-CDI v10r1c0) So the next sell will be in April…

      I had good feedback from the guy who tested it on Yamaha XT200 – 1982. Some videos will come soon.
      PS: ACCDI v9 was Wifi but it’s End Of Live now. ACCDI v10 is much more accurate than v9

    1. Hi,
      thanks for your interest. The last one will be available next week and before 31 of May.
      Then a period of 2 or 3 weeks for restock then a bunch of 10 should be ready.

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