I have just inherited a K1100LT with 30,000 miles on it that has been sitting in a garage for the past seven years. I have installed a new fuel pump along with a new sending uint because the old ones were rusted and gummed up from the old fuel. I had to also to replace the ICU because the original was lost when the battery was removed somewhere along the way of storage for the past seven years. 
The bike starts up everytime and as soon as it is warmed up it seems to be running fine. It just seems to have no get up and go to it. While running at 60mph I can increase the throttle and it seems to take about five to ten seconds before the bike starts to pick up more speed. This is my first BMW but it seems to have no power.

If your bike is a 2 valves per cylinder...
This could be a result of a sticky Mass Air Flow sensor(MAF) or maybe simply a sticky Throttle Position switch(TPS).

First thing to do is to disconnect the TPS.

Three or four tanks of 91 octane with a half bottle of Techron.  Get it out and open up the throttle and flush the injectors and fuel pressure regulator.

Have you checked the air filter box and filter it's a favourite place for mice to make a nest.

Crazy Frog wrote:If your bike is a 2 valves per cylinder...
This could be a result of a sticky Mass Air Flow sensor(MAF) or maybe simply a sticky Throttle Position switch(TPS).

First thing to do is to disconnect the TPS.

If your bike has two valves per cylinder then it is not a K1100.

duc wrote:If your bike has two valves per cylinder then it is not a K1100.

OOPS, my bad! I didn't pay attention. 

I pulled the air filter out and checked the air intake along with the air filter box. All was clean and it is quite a job with all the fairings on this bike. But a least that is one item to check off my list.
I will run it as much as time allows to push a couple of tanks of gas through it. And yes I'm running high octane.

I'd be inclined to do a few checks first before you go running it for any long length of time.
I was going to suggest reading some of the info off the portal page but yours is a 4v 1100 so some of that may not be all that relavant.
Quite often you'll find it's just something simple

• First check your battery for static charge as well as the charging voltage from the alternator.
  

• Check your brakes aren't rubbing.
  
• Check your SPs for colour. They'll tell you quite a bit about what's happening fuel wise. Dark and oily or clean and dry (rich/lean). This will tell you if you are getting too much or too little fuel.
  
• Try new SPs or test the old ones with a multimeter.
  
• What's the tail pipe look like? Soothy or clean?
  
• Test the water temp sensor. Is it eathing? Does it return the correct impedance-to-temp reading?
  
• If the engine runs smooth and idles, I doubt it will be the injectors but if they're old and haven't been serviced for a while the O-rings may be leeking air into the intake. A new kit will fix that. Crankcase breather could be doing the same.
  

Sounds like an air/fuel/mixture issue to me.

Good luck

Ok I have ran about three tanks of 93 octane with techron additive, still low power. Its soiunds like the bike is not getting enough fuel. What should my fuel pressure be? I replaced the old fuel pump with an after market fuel pump. When I turn the key on the fuel pump comes on every time, also there is fuel returning to the tank everytime I turn the key on, is this normal? Even if I never start the bike but just turn the key on and off for about five times the fuel pump comes on and fuel is returning to the tank.

Are you seeing evidence of a lean fuel mixture?  Is the loss of power due to fuel starvation? Does the engine ping at full throttle under load?

My gut feel about your observations is that even if the fuel pressure regulator is working to control pressure in the rail, once the rail is pressurized fuel will be returned to the tank.  If you have ever disconnected a fuel line you will know that the fuel system stays pretty well full of fuel and thus won't take much to re-pressurize and then dump fuel back to the tank.  Bottom line is that it sounds to me like you are getting fuel to the rail, it just isn't getting to the cylinders.

I don't recall how long you said the bike sat without running.  Since it sounds like some fuel is getting to the cylinders I suspect that the injectors may be gummed up beyond what a couple tanks of Techron can remove.  There are videos on YouTube that cover ways to check and clean injectors.  Some are fairly simple.  One place to check is the filter screen at the top of the injector.  I haven't done it myself, but I understand they are fairly easy to change, and the filters can be had on eBay for a couple bucks each. 

I would go there next or possibly send them out to a shop that specializes in cleaning/rebuilding them.

diveshadow wrote:I have just inherited a K1100LT with 30,000 miles on it that has been sitting in a garage for the past seven years. I have installed a new fuel pump along with a new sending uint because the old ones were rusted and gummed up from the old fuel. I had to also to replace the ICU because the original was lost when the battery was removed somewhere along the way of storage for the past seven years. 
The bike starts up everytime and as soon as it is warmed up it seems to be running fine. It just seems to have no get up and go to it. While running at 60mph I can increase the throttle and it seems to take about five to ten seconds before the bike starts to pick up more speed. This is my first BMW but it seems to have no power.

Just rereading the original post. You say a new sending unit?  and are you sure you have the correct ECU there are several variants among them even the R1100 ECU will plug into the bike but not sure if it will actually start and the K model units have different units depending on whether you have O2 sensors or a CO2 adjustment. Its the colour of the label that tells you which it is IngeK knows more about that than I do.

"The bike starts up everytime and as soon as it is warmed up it seems to be running fine" 

.... I doubt it would be injectors or fuel pressure. If they were blocked or fuel pressure was low, I think it would be hard to start, running very uneven with poor idle.

What sort of throttle response do you get from idle, with no load ie; in neutral

Honestly... check your spark plugs. That will tell you if its running lean or rich. Also, you'll get poor fuel ignition and low power if they don't have a good spark. The SP washer can flatten out and start to leak so you could be losing compression.