One thing I have noticed, and do correct me if I'm wrong, is that the IPL speed gun is clearly adding a few clicks to some bowlers. I mean I saw Bhuv hit 140kmph for the whole overy and there has been other instances through out the IPL.
Bhuvi does bowl in early 140's when he is in rhythm. There is nothing wrong with the speed gun. In fact one of the reason why he lost his natural swing recently was because he focused too much on increasing his pace. He has definitely increased his pace but in that process, lost his swing which was his strength and therefore struggled last year. Seems like he is doing decently in the IPL but needs to show that when he playing for India to retain his place.