hi i want to make a cdi with rev stop does anyone have a schmatic or know how to start the project
found a cdi that has what I'm looking for but want to make my own miun as there is always poor quality of compinents

 

How accurate do you need the rev limiter to be??OR is it to actually be a speed limiter? And do you simply want ignition cutoff, or just every other spark missing? Or some other mode??
Would it be battery system powered, or generator system powered, or magneto powered??
Details matter.
Also, is this for a MOPED, a motorcycle, or an automobile? And how many cylinders in the engine??

 

How accurate do you need the rev limiter to be??OR is it to actually be a speed limiter? And do you simply want ignition cutoff, or just every other spark missing? Or some other mode??
Would it be battery system powered, or generator system powered, or magneto powered??
Details matter.
Also, is this for a MOPED, a motorcycle, or an automobile? And how many cylinders in the engine??

Hello! I don’t want a speed limiter; it should be an RPM limiter. The CDI should be powered by AC, and I want to take the pulses from the crankshaft trigger. I’d like to be able to set an RPM limit between 3000 and 7000 RPM using one or more buttons, preferably with an "antilag" function if possible. It should be powered by the trigger pulses (I think this should work). This is for a moped with a standard GY6 engine one cylinder.

 

OK, now it is interesting indeed. An adjustable limit set "with one or more buttons", which, if there was a display included could be : UP, Down, and SET, allowing a lot of adjustability. The "simple" rev limiting scheme is to set a timer that is triggered by the pickup and closes the trigger gate for the next pickup pulse until the time is done. That scheme enforces the RPM limit by stopping every other ignition firing when the limit is reached. It is the equal of the dwell time extender limiters used in the 1960's era.
That scheme will require a small processor to implement.

 

OK, now it is interesting indeed. An adjustable limit set "with one or more buttons", which, if there was a display included could be : UP, Down, and SET, allowing a lot of adjustability. The "simple" rev limiting scheme is to set a timer that is triggered by the pickup and closes the trigger gate for the next pickup pulse until the time is done. That scheme enforces the RPM limit by stopping every other ignition firing when the limit is reached. It is the equal of the dwell time extender limiters used in the 1960's era.
That scheme will require a small processor to implement.

worked a little on this sketched in kicad think this should be right if you want to get a rev stop limiter. By using a microcontroller though, I don't know exactly how much volt is coming from the motor pulses to the trigger

 

worked a little on this sketched in kicad think this should be right if you want to get a rev stop limiter. By using a microcontroller though, I don't know exactly how much volt is coming from the motor pulses to the trigger

A series resistor and a power diode 4 diode series clamp circuit clamp can limit the pulse to about 5 volts. and one reversed diode in parallel to clamp any negative voltage.