Cooter69

I am new here don't kmow how this works I have picked up a 1982 XS400J Have cleaned the carbs gas tank, have spark on left side no spark on right side until ya let off the starter button. a few very loud backfires that is all I get hopen some one can help with this problem

I just joined 03/20/2012 been reading about 400 I just recived a 1982 Yamaha Maxim It is red and it was made 03/1982 but not real sure what it is ??? XS400J or what could use a little help please