[tcthomp66]

The headlight lamp is actually a good place to start. If the wattage was increased, it potentially could place a higher load on the system and reduce the power to the electrical starter system.

First, check your lamp socket for any corrosion. It can increase resistance, which will lower the output to the starter system.

Second, try removing the lamp and shorting the leads for the lamp together and then starting. If it starts, then your issue is in the headlight area. I would replace the socket and the lamp. (I know this may sound silly -- a lamp is essentially a fuse that provides light. However, I have seen improperly manufactured lightbulbs short or load a system before.)

In the future, there is an old axiom that I hold near and dear to my heart... If it worked before but doesn't work after I made a change, go back and check the change.