CDI for XT400-550-600

Why a home page on the XT600 Yamaha electronic ignition?

Incidentally! Following the third CDI out of order on my motorcycle bought in 1986, I was in front of a dilemma… What to do of this worthless bike?

– To throw it !
– Buy a new ignition in a scrapyard? (about 150 €uros, very difficult to find and no guarantee that it works)
– Buy a new ignition at 465 €uros? This is approximately what the bike worth!
– A last, a not investigated possibility remained: a DIY CDI! Hence this web site…

I suggest 5 differents ways to build your own CDI, hoping that my experience will be useful for other bikers.

 

What will you need to build YOUR OWN CDI?

  1. A few mechanical knowledge.
  2. Electronics skills.
  3. Measure equipment (multimeter, scope 2 channels if possible).
  4. The Workshop Manual obviously.

The simple ignition and the programmable ignition have been tested successfully on models 34L and 43F (1983-1986) SRX600 XT550 XT400 (see the list of the codes yam 237Ko)

You need to know how the sensors works. How to test the ignition sensors?

 

Description of those five ignitions.

Analog CDI

  • Easy to build.
  • 12 components for 5€ !
  • Advance curve slightly tuneable.
  • Need a alternator for charging the capacitor.
  • Don’t need a battery

 

CDI with µproc PIC 16f628 Version6

  • Adaptable to other mono-cylinder bikes.
  • High precision (0.07 degree).
  • Preprogrammed for XT400/550/2strokes (84 or 106 points).
  • Software source unavailable (only .HEX).
  • Need a alternator for charging the capacitor.
  • Need a battery

 

CDI with µproc PIC 16f628 Version7

  • Adaptable to other mono-cylinder bikes.
  • Precision (0.5 degree).
  • Software source unavailable (only .HEX).
  • Advance curve is in EEPROM and can be freely modify
  • Need a alternator for charging the capacitor.
  • Need a battery

 

CDI with µproc Atmel AT90S1200

  • Adaptable to other mono-cylinder bikes.
  • Tuning of the advance curve (4 points).
  • Software source available (.ASM).
  • 10.000RPM max
  • Precision (1.2 degree).
  • Digital display of RPM and temperature.
  • Need a alternator for charging the capacitor.
  • Need a battery

 

DC-CDI with µproc Atmel AT89C2051

  • Adaptable to other mono-cylinder bikes.
  • Tuning of the advance curve (255 points).
  • Software source available (.ASM).
  • 7.500RPM max
  • Compact & economic.
  • Don’t need a alternator.
  • Need a battery

 

Summary of AC-CDIs

Features Analog V5 V6 V7 Atmel

Ajustable steps 2 131 225 95 245
Battery needed No Yes Yes Yes Yes
Programmer needed No Yes Yes Yes Yes
ASM available Yes No No Yes
Quartz No Yes No No Yes
RPM Limitation No Possible Possible No Possible
Microprocessor No 16F84/16F628 16F628A 16F628A 89C2051
Accuracy bad 1° to 5° 0.07° 0.5° 1.2°

Cost in €uros 5 30 30 30 ??