Those old Shovels are difficult to start sometimes. But, never make the assumption that a battery is good. Take it to an automotive parts house and have them check the battery. There is usually no charge for this service. If the battery is in NEW, has it been charged and does it have sufficient cold cranking amperage (CCA) to do the job. It takes at least 250 CCA for that bike with it 80 cubic inch engine. If you live in a very cold climate and you're running 60 weight oil in the engine, you need an even stronger battery.
Next, are all the connections good? Not only the connections to the battery but also the ones to the solenoid, starter, and the frame ground.
If everything I've mentioned here checks out and still makes that clicking sound, it could be several things. Where is the clicking sound coming from, the solenoid or somewhere else? If it's coming from the solenoid, the contacts in the solenoid could be burned. Disconnect the battery and all the connections on the back of the solenoid. One each screw terminal on the solenoid, there's a nut. Take these off as well. There are two screws left, take them out and carefully pull the black end cap off of the solenoid. Now look at the two bolt type connections that are made of copper. One or both of them may be badly burned and recessed. Notice the washer on the plunger inside of the solenoid. Does it look burned. If one of the bolts is badly burned with a recess that matches the edge of the plunger washer, you can turn it around 180° and reuse the bolt. If everything looks good, carefully reassemble the solenoid. If you try to tighten any of the nuts or the two screws, you can bust the phonelic cap rendering the solenoid useless. You can buy a solenoid repair kit if needed.
If the click is not coming from the solenoid, try to locate exactly where it is coming from. There is a starter relay that is usually located somewhere around the battery that will make a clicking noise. It's one of the plastic cube type about an inch cube. If this is making the click but not starting the bike, you need to use a test light on the small terminal of the solenoid. When the relay clicks, you should get power to the small terminal of the starter solenoid.
To test the solenoid, first make sure the bike is out of gear. Take an old screwdriver or something, on the back of the starter solenoid, jumper between the large terminal that the cable from the battery connects and the small terminal. When you do this, the starter should turn the engine over. If it does, your problem is before the solenoid and the starter. If it doesn't turn the engine over, it's either the battery, solenoid, or the starter.
If you still can't get you old Shovel running, contact me directly at firstname.lastname@example.org