Ignition system

[CWells]

I have an old 1-cylinder 2-cycle engine that has bad points. I can't get new ones, and I really don't want to pull the flywheel off of it.
I was wondering about the possibility of making an ignition system, with either a Hall effect sensor, or perhaps an optical sensor. Would a Picaxe be fast enough for this? Max rpm would be about 4000-5000...if the Picaxe can't do it, what are some faster microcontrollers that aren't too expensive, and where could I find schematics/diagrams of CDI or other electronic ignition systems?

 

[demonicpicaxeguy]

a normal pic running at 4 mhz would hande that with time to spare or maybe a picaxe 28x2 running at top speed

 

[papaof2]

Try some of these links.

http://www.highlandsun.com/hyc/ignition/

http://www.freescale.com/files/microcontrollers/doc/app_note/AN4006.pdf

http://www.freescale.com/files/microcontrollers/doc/app_note/AN2159.pdf

http://www.sportdevices.com/ignition/ignition.htm

http://catherine.myhab.net/favorite/sj10_image/diode.pdf

list of magazine articles: http://www.nleindex.com/index.php?pID=HTDI&sID=BrowseIndex&tID=E/99

http://www.st.com/stonline/products/literature/an/5201.pdf

http://www.foxvalleykart.com/timing1.html

 

[Charliem]

Hi Chris,
This may help.
<A href='http://www.jerry-howell.com/IgnitionModules.html' Target=_Blank>External Web Link</a>

 

[gengis]

Two cycle engine? Magneto? or &quot;energy transfer magneto?&quot; (coil separate from pickup inductor). Does it use a battery for ignition?

All the Brigs and Stratton I've worked on (are four cycle) and use magnetos. All the outboard marine 2 cycle are energy transfer magneto systems (from 4 HP to 150 HP)

In the case of Brigs - they offer a solid state replacement that seems to be nothing more than a thyristor triggered with a coil - very inexpensive, but gets rid of the points.

SS replacement was around $9 and points $3 last time I checked - and you'd still have to pull the flywheel.

Outboard marine switched to SCR a long time ago but you can still find parts for antique point style magneto systems.

Not everything is replaceable with a PIC and sometimes it makes very poor sense to try.

Perhaps a gear puller, skinned knuckles,arm waving, head-scratching and cursing will fix it faster.

If I can fix a scanning electron microscope - I can damn sure fix a lawnmower - or that's what I tell myself.