Can anyone explain the engineering theory behind the fact that the current Yamaha 90 hp two stroke motor has a compression ratio of 5.76:1 in cylinder 1, a compression ratio of 5.67:1 in cylinder 2 and a compression ratio of 5.86:1 in cylinder 3. The 70 hp two stroke which is also a 3 cylinder engine has a compression ratio of 6.1:1 in all 3 cylinders.