Flight Suvarnabhumi Airport departs from Bangkok Suvarnabhumi Airport at 10:15 and arrives at Chiang Mai Chiang Mai International Airport at 11:30.
The flighttime is about 1h 15m. The distance travelled ("as the bird flies"): 221 Km. So the average speed is roughly 177 Km.
The best day to arrive at Bangkok is Tuesday and it would be best to avoid Friday, as prices are on average 59.02% higher than on Tuesday. (Average prices, based on 11067156 datapoints.)
We have a lot more statistics for flights TG 104 and between Bangkok and Chiang Mai.