Hey all so a few months back I purchased a 1985 red k100rt which had been sitting for about ten years. I've changed the fluids and filters and she cranks just fine but no fuel is being pulled by the fuel rail, I hooked up my external gas tank to test it.  I suspect it's the fuel pump, I can't hear it click when I turn on, and so I went ahead and ordered another one figuring that one of my two k100's probably needs it or at least will in the near future. It will be here Sunday and was 50 bucks with Amazon prime. 

My second k100 is a 1987 white k100rs with 19,002 miles that has sat Ina garage for ~18 years. I have also changes its fluids filters and tires and it doesn't start either but I can't verify whether it pulls any fuel into the rail because I haven't pulled the tank yet. All the lights work on both bikes. 

Any suggestions are much appreciated.  

Welcome to the forum. You will find that that fuel filter should be changed as well. Anything that normally  is covered by fluid and has rubber will perish so the pump may be ready to throw away. You may also have problems with the water/oil pump as it likes to be active and gets grumpy and hard when resting for too long. Luck may be with you and the seals only may have to be replaced. In the US one person you need to listen to is Two Wheels Better.... an Aussies on  leave from our shores... he also works at a BMW dealership. Good luck.

Welcome to the forum.
You won't hear the pump click when you turn the ignition on. Just a buzz when you press the starter button. If the engine doesn't start it will buzz for a couple of seconds after you release the button.
Common problem if they've been sitting for a while is that the connector to the tank and, hence the pump, can corrode and go high resistance. Worth checking and cleaning.
Whatever it is, it won't be serious.
Fuel filter change is a good idea. Don't ask me how I know.

Thanks for your replies, I will change the fuel filters and swap the pumps on Sunday and post again with the results, I have never heard that buzzing you're talking about so I think both might have shot fuel pumps