Does the motor have mechanical points - or is the ignition Electronic? - Some small 2 strokes have electronic modules that work on the dV/dt of the low tension coil output and use a transistor to take the place of points. If this is the case, you might have to figure out which is the low tension coil connection and tap into it - if that's the way you want to go. Another "Quick stop" possibility might be to have a spring loaded lever poised over the (bare) spark plug terminal. This is released by a soleniod (Or held in place by a solenoid) and shorts out the spark to stop the motor. Doing it this way would not require changes to the ignition system. Richard P Dale Botkin cc: Sent by: pic Subject: Re: [PIC]: Building a Servo microcontrolle r discussion list 10/08/01 09:06 Please respond to pic microcontrolle r discussion list On Thu, 9 Aug 2001, Mike Kendall wrote: > > :( The motor I am using (and no I can't change the kind of motor being > used! > > :) )uses a "coil flying by a magnet really quickly" approach to develop > the > > spark. > > Isn't that a "magneto" ignition that you are describing, similiar to the > old 2 cycle dirt bikes? > Regards, And lawnmowers, and chainsaws, snow blowers, Formula 500 race cars, and most small airplanes. Dale -- A train stops at a train station. A bus stops at a bus station. On my desk I have a workstation... -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu