Mark, If your Jawa has a Selectra mag and coil on it, all you have to do is ground the coil using the Black/White wire coming off of the coil or just attach your switch to the coil frame. This does not harm your coil. It just grounds the primary pulse and the coil never gets a chance to charge. Use a good high amp switch or it will shock the crap out of you if you flip it at 8K rpms.