The 05 has an auto decompression cam and it works properly. I just replaced the starter relay. There is also a shutoff relay but I don't think it can affect the performance of the starter. It either allows the main starter relay to activate or it doesn't, depending on whether the bike is in neutral or the clutch is pulled in. I also tried jumping the relay which didn't help and I tried directly bypassing the relay with a car battery which also didn't help. I'm tempted to replace the wires going to the starter but I don't measure any resistance in them. I think it is something in the motor. My kick starter doesn't hangup. It works properly. I've taken my torque limiter out and I can't find anything wrong with it. I am guessing it has to be the starter clutch, but I don't know anything about it. I don't understand how the starter clutch could add resistance during the start but not while running. If there was any added resistance while running, parts would overheat quickly and something would fail. I guess I need to take the case apart and check the starter components.
also, I did the blue/white wire mod which was very beneficial for kickstarting and e starting at the same time. I had this problem before I did that. I did the mod because I was having to kick and e start at the same time.
The bike does have a lot of compression and is hard to kick but I assume every wr450 is like that. I literally ripped a hole through the sole of a cheap pair of boots over the course of a couple rides from kick starting it. I should probably have a mechanic start it. Someone that would know if it is harder kick than other bikes.