Just to eliminate other problems/solutions,I thought I'd start off with some things that are already checked off. My 09 FJR is topped off with coolant. At the same time, the water pump appears to be working just fine. All hoses and connections are securely tightened, so there are no leaks. I also burped it a time or two in order to get rid of any air bubbles in the system.
Every time I start the bike, the temperature gauge steadily climbs to where it's at the very top. This is especially the case when I put it into gear and go around the block a time or two. There's also been a couple of cases where the bike gets pretty hot at first, and then cools down and retains a good temperature throughout the rest of the ride.
This particular problem first started when I had to take cooling pipe out in order to access a wire and fix an electrical problem. Since then, I also had to buy a new pipe, because the old one seemed so bent, I couldn't fit it back into the cylinder head. The new pipe I received fit just fine with a new pair of O-rings. There's no leaking of antifreeze anywhere. Any ideas?