ACCDI v2.7 up to 350cc
ACCDI v2.7+ for above 350cc
Repair your vintage motorcycle with this ignition!
Affordable and easy to install, it fits a wide range of models, boosting reliability.
|Easier||Every function has its own DIP Switch. No jumper to cut or to solder.|
|Universal||More DIP Switches to adapt to different engines.|
2 trimmers to adjust timing.
|Safe||2 types of input to stop the ignition: Ground to Kill and Power to kill.|
|Powerful||V27: For 50 to 350cc engine with a 1uf capacitor.|
V27+: 50% more energy for bigger engine from 350 to 800cc with a 1.5uf capacitor.
|Reliable||V27+: High quality trimmer. (Piher, European brand)|
High voltage ranking capacitors. (400volts)
Drill the cover to pass the wires.
Once you are done for ever with settings, pour the box with PU resin or silicon sealant to make it waterproof.
Fill up the wiring hole with hot glue.
This ACCDI fits in this IP54 box.
IP54 rating means protected against solid objects and dust but is not fully dust tight (5 out of 6).
and protected against water splashing from any angle but not waterproof (4 out of 6)
How does it works?Click here for more info
On an ACCDI based engine, the charging coil (AKA stator) puts out:
– LV (Low Voltage of around 12Vac) for light and battery if any. (Lighting coil)
– HV (High Voltage of around 100Vac) to charge the ACCDI. (Charging coil)
This AC-CDI only uses the HV coil to charge a capacitor through a rectifier bridge.
When the pickup is triggered, the CDI turns on a thyristor that discharge the capacitor inside the primary of the ignition coil.
This burst of energy into the primary induces a high voltage of few thousand volts into the secondary wiring of the ignition coil, enough voltage to create a spark at the sparkplug contacts.
PICKUPClick here for more info
– This CDI works with 1 pickup and 1 reluctor (the metal strip on the flywheel) [A,B].
– This CDI works with 2 pickup and 2 bars [E,F].
– This CDI DOES NOT work with 1 pickup and multi-pulses pickup (ie 2 reluctors on flywheel) [C,D].
– This CDI DOES NOT work with 1 pickup and missing tooth flywheel [G].
– When the engine has only ONE pickup, the 2 wires are connected to HI and GND inputs.
– When the engine has TWO pickups (for Low speed and High speed), the 3 wires are connected to HI, LO and GND inputs.
– When the rising edge of the bar on the flywheel comes in front of the pickup, a pulse is generated.
This first pulse is used by the CDI to spark at high revs.
– When the falling edge of the bar on the flywheel leaves the pickup, another pulse of opposite polarity is generated.
This second pulse is used by the CDI to spark at idle.
A pickup has 2 wires.
– If you ground wire number 1, wire number 2 will put out a Positive pulse first when the rising edge comes, then a Negative pulse when the falling edge leaves. I call it PN.
– If you ground wire number 2, wire number 1 will put out a Negative pulse first, then a Positive pulse. I call it NP.
A genuine Yamaha pickup is often Positive first then Negative (PN) but if you swap the 2 wires of the pickup, the polarity will be Negative then Positive (NP) therefore the DIP switches setting for PN will NOT work anymore of course !
Solution: Rectify the pickup connection or use the settings for NP engines.
Be careful: If the wires are swapped then the pickup polarity will CHANGE !
To find the polarity connect the pickup to an “old” Analogue meter set to it’s lowest voltage setting (around 1volt).
When a non-magnetized steel object (eg a screwdriver) is approached and comes into contact with the top of the magnet the meter needle will indicate a momentary deflection (ie – negative or + positive volts).
When the screwdriver is removed from the magnet’s top the meter needle will show a brief deflection in the opposite voltage. See: Video
HOW TO SET DIP SWITCHES?Click here for more info
You have to know if the bike has 1 or 2 pickups.
Then refer to those lists of settings for bikes with 1pickup or 2pickups
Also you have to know for each pickup what is the polarity:
PN (First pulse Positive then second Negative) or NP (Negative then Positive).
Connect a scope between Ground and pickup wire to check the polarity.
If you don’t have a scope at hand, you can see the polarity with an old voltmeter.
SW14-1, SW14-2: Advance timing
4 strokes engines: set Switches N°1 and 2 of SW14 to OFF (default).
On 2 strokes engines it’s necessary to lower the advance at HIGH RPM:
2 strokes with Small reduction of timing : set Switch N°1 of SW14 to ON.
2 strokes with Medium reduction of timing : set Switch N°2 of SW14 to ON.
2 strokes with Large reduction of timing : set Switches N°1 and 2 of SW14 to ON.
SW14-3, SW14-4 : KTM setting
All engines, set Switches N°3 and 4 of SW14 to ON (default).
KTM engine, set Switches N°3 and 4 of SW14 to OFF.
SW14-5: pickup Sensitivity
Pickup that puts out 2 to 30volts, set Switch N°5 of SW14 to ON (default).
Pickup that puts out 30 to 150volts, set Switch N°5 of SW14 to OFF.
Sensitivity Fine tuning
The Sensitivity of the CDI to detect the first pickup pulse (at start and idle) is adjustable with RV2 potentiometer.
– Start the bike with RV2 at max value (4)
– Try different position of RV2 from (4) to (0) to find which position gives the easiest start with no kickbacks.
SW14-6: Not used
Can be on or off.
TIMING ADJUSTMENTClick here for more info
This CDI doesn’t have seamless advance, it jumps from LOW advance to HIGH advance.
The RPM when the CDI jumps from Low to Full advance (in fact when it switches from the first pickup pulse to the second one) is adjustable with RV1 potentiometer.
– Run the bike at idle with RV1 at max value (4)
– Try to rev up the engine while slowly unscrew (toward 0) until the bikes wants to rev up.
– When she wants to rev up you’ve got the setup.
|2200 rpm with RV1 at 4:
CDI uses the second pulse = Low advance
|2200 rpm with RV1 at 1.5:
CDI uses the first pulse = High advance
INPUTS OUTPUTSClick here for more info
A Kill switch input is available “K“.
Ignition stops if connected to GROUND.
A Safety switch input “S” is available (for Side stand, Clutch, Neutral, Main switches…)
Ignition stops if connected to a positive voltage from +2v to +12Vdc.
– If the charging coil is internally grounded, then connect the only wire to “ALT” input and leave “ALTg” not connected. Note that DIP SW13-6 will have no effect.
– If the charging coil is NOT internally grounded, then connect the 2 wires to “ALT” and “ALTg” inputs.
Order has no importance.
SW13-6 DIP ON: Less voltage.
SW13-6 DIP OFF: More voltage (default).
A tacho output “TAC” is available. The output voltage is +12v (even if no battery or 6v battery)
Notice that it’s not a pure square signal.
Connect a tachometer that does NOT need a 50% square signal (50% off, 50% on)
Click here for more info
You will need a DC voltmeter. The best is an old “Analog Needle meter”.
Download troubleshoot step1
– Don’t connect any pickup.
– Don’t connect the Kill Switch or any Safety switch.
– Connect the GND plug of the CDI to the ground (minus battery or motorcycle frame)
– Connect the ignition coil to the COIL output of the CDI.
– Remove the sparkplug from the engine and connect the metal body to a GOOD metal frame (an unpainted bolt).
– Connect a DC voltmeter between GND(ground) and KILL pad.
– If the stator/charging coil IS NOT internally connected to ground, it has 2 wires:
– Connect any of them to ALT and the other to ALTg input of the CDI.
– DIP Switch SW13-6 can be ON for full rectification or OFF for half rectification (Don’t hesitate to test both position).
– If the stator (charging coil) IS internally connected to ground, (One wire is already internally connected to ground):
– Connect the only output wire of the charging coil to ALT input of the CDI.
– DIP Switch SW13-6 has no effect. (can be on or off).
Other DIP switches positions don’t matter for step 1.
– Electric start or spin the engine with a drill or Kick start a few times to load the capacitor.
The voltmeter should raise up to 100 or 200Vdc then quickly decrease.
(Due to the capacitor discharging into the CDI and the voltmeter).
If not: Check grounds, connections, joints, charging coil (stator), change switch 6 position.
Download troubleshoot step2
– Same connections as Step 1 (Still no pickup, no kill nor Safety switches connected.)
– Turn SW13 DIP Switches positions 1, 3, 5 to ON.
– Turn RV1 to the minimum resistance (Position: 0).
– Kick start or electric start a few times to load the capacitor.
– Once the main big capacitor C1 is charged and the voltmeter shows 100 to 200Vdc, then in the same second:
– Connect the + 12v battery to HI input:
– Labeled “P” Led turns on.
– The big Capacitor discharge into the ignition coil and one spark must fire at the sparkplug.
If not: Check grounds, connections, joints, SCR, ignition coil, spark plug cables, spark plug.
Redo this Step 2 but this time connect the +12v battery to the LO input. (Led won’t light.)
Download troubleshoot step3
– Same connections as Step 1 ( Still no pickup, no kill nor Safety switches)
– Turn SW13 DIP Switches positions 2, 3, 4, 5 to ON.
– Turn RV1 to the minimum resistance (Position: 0).
– Connect the pickup coil between a GOOD metal frame (ground) and HI input of the CDI.
– Kick start or electric start to load the capacitor and send trigger pulses:
– The main capacitor C1 is charged and the voltmeter should read 100 to 200Vdc.
– At the same time, when the piston approaches the TDC and passes in front of the pickup, a pulse is produce by the pickup:
– LED blinks. (P or N or both leds according to the type of pickup)
– The pickup pulse then trigger the SCR and the big capacitor C1 discharges into the ignition coil, a spark must fire at the sparkplug.
If not: Check grounds, connections, joints, pickup coil, RV1 is set at 0, reverse the 2 wires of the pickup coil.
Suzuki GN400 with ACCDIv27+
Marty bought a 1984 wrecked XT600 without ignition and harness wiring.
Got it running again even if it seems like he has some carbs works to do…
Click here for more videos
Pickup polarity (PN or NP):
Analog CDI v2.4 on a XT125/1982:
Analog CDI v2.4 at 15,000rpm: