Another vote for looking at the points.
A few things to add, replace your plugs and make sure the HT leads and coil are also in decent shape.
Make sure the battery has a nice full charge. Double check all the grounds, especially the ones in the ignition and starting wiring.
These bikes bounce and vibrate and stuff can get loose. Get a weak spark slightly foul the plug up and stuff spirals quick.
On vacation for a spell