I've only seen one other do that.....and it was mine. 250 XS Opti with a Sportmaster. I pulled my hair out trying to figure why I had a 89 mph porpoise.After all was said and done.....the stringers had separated from the bottom of the boat. Stratos crushed that one. All had a porpoise between 55-65......but if you're way up there in speed you need to have it looked at professionally.
