difference in yamaha 150 vs. 200

[ngleo]

I have been looking at the specs of the 150 and 200hp yamahas. It looks like the same motor except for .2 difference in compression ratio. Does this get 50 more hp out of the motor? All things being equal, would the 150 be more durable than the 200 since somehow it must not have to work as hard as the 200?

[PeteH]

Port timing (the location of the intake and exhaust holes in the cylinder), carbs, reed assemblies- all different. As for durability, in this case the 150 is underbuilt as opposed to the 200 being overbuilt. Both are very sturdy.