The Hull of the Rio 51 is brilliant! Very strong and very light!
They pretty much all leak from the rear where the strut goes through.
All you need is a lil epoxy on the inside of the hull down the back and she'll be sweet!
It is true, the Fugi motor in them are useless, alot of torque, no Revs!!
Same goes for the exhaust header and muffler, if your header hasnt cracked yet, wait for it its coming. And if you use your boat in salt, the mufflers corroding from the inside out lol
They are also a pain at first to start, but to there credit once you have them dialed in it starts every 2nd pull. Ive since replaced with the Zenoah/ Hanson pipe and its now an awesome boat!
When starting, ( of course with needles on carb in the right position )
Pull plug off, pump primer till fuel up, put choke on, pull 2-3 times with choke on, put plug on, pull once more with choke on then turn choke off. Now Pull and she should start. My friend and i have the same boat and both swear by this routine.
Anyway, hope theres some help for ya! P.s get a shaft saver...