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For those interested in learning about Maverick Spark ...I put together scans from several articles:

One of those old-timey left hand threaded sparkplugs! Almost as good as the article that had an eight-sided wrench flat area. T

Jeff

Thanks for going to all the work to post it. Way Cool

eeeeek that page turning noise is sick!!!! (in a good way)
love the articles format.
great work.
dave

David,
Try left clicking on the page corner, holding the mouse button down, let's you grab the page so you can flip it with the mouse ... even "sicker" than the sound?

Jeff

VERY COOL

dave

By Bill Hermsted;

Hello Jeff;

Can a well modified Power Products AH 58 go into maverick spark, or are only the Macs able to do this
consistantly?
Take care, Bill

Bill,
Here is a little article I wrote that gives a quick overview of what Maverick Spark is all about:



... any point ignition system on a high reving 2-stroke will go into Maverick, the points will float once the rpm's climb. On most engines, the position of the flywheel magnets matches the normal point timing ... so there is no significant advance of the ignition timing. Engine tuners making use of the Maverick affect, will advance the flywheel magnets to create an "automatic" timing advance that kicks in when the points float and the ignition goes to Maverick. This is why McCulloch came out with the "5 degree" flywheels, the magnets are advanced 5 degrees relative to the key slot.

Going to your question about the AH-58 ... you can play with making offset flywheel keys out of round stock .. or simply file off one side of the key to advance the magnets. If you try filing off a key, or not using a key at all .. you will have to lap the flywheel to the crank using a lapping compound (available at most auto stores). Another vintage authentic alternative to using point float to control where your Maverick comes in, is to put a Maverick ignition button on your steering wheel, wire it so that pushing it, opens the point circuit (as opposed to grounding it as a kill switch would do) ... you hit the button maybe a 1/3 to 1/2 way down the straight, if the flywheel is advanced, it should provide a slight kick.

With all of this, do be careful ... too much ignition advance can lead to detonation and/or over heating, which usually ends badly for your poor old vintage motor!

Jeff

Hello Jeff;

Great article! I'm finally beginning to understand.
Ever since a kid my dream was to make a two cycle turn ultra high rpm's, like a modal airplane Cox .049!
I never thought that the breaker points' floating tendency, the usual barrier against high rpm, could be exploited in this way to reach maverick.
As for being careful with the spark advance, it's obvious now why you racers like alky!

Thanks,
Bill

Remember you will either run into the mechanical limit of the engine and blow it up, or the heat limit of the engine to dissapate heat and seize it up...........