Hard shifting 2005 speed triple 1050

I'm new to triumphs and just bought a 2005 triumph speed triple with 37,000 miles on it. I was told the bike has been regularly maintained and had all the necessary maintenance and check ups done on it but I seem to be having some problems. Some times when shifting between gears (from first to second seems to be the worst most often) the bike won't shift or has a very hard time shifting. It seemed like it was happening only when the bike was cold after 10 miles or so it wouldn't get stuck in gear. I changed the oil in it and used the recommended 10w 40 fully sinthetic Mobile 1 racing 4t and it seemed to fix the problem for a while but the issue came back not 100 miles later. It's better now that I have changed the oil but it still will get stuck in a gear and not allow me to shift sometimes unless I rev the engine up to about 5,000 rpms with the clutch in while moving, when I do this it will slide right in to gear. Other times when shifting it will miss the gear and ratchet around until finally sliding in to gear (the ratcheting symptom has only happened a couple times). Before changing the oil these symptoms would happen everytime the bike was cold until about 10-15 miles of riding with out fail and it was pretty extreme taking me multiple trys to change gears. Since changing the oil it is not nearly as bad but I've still noticed it getting stuck in gear sometimes still. If anyone has any ideas or if the occasional hard shifting is normal for the speed triple please let me know!! I just want to know if I bought a bum bike for $4,300 and what I have to do to fix the problem. Thanks.