When two boats share the same hull type — in this case both the Alumacraft Riveted Jon 1236 2011 and the Alumacraft Riveted Jon 1648 (15 & 20) 2012 are flat designs with aluminum construction — the buying decision usually comes down to a handful of practical questions: how many people are you putting on the water, how far do you trailer, and what does your tow vehicle weigh?
Size is the most obvious dividing line here. The Alumacraft Riveted Jon 1648 (15 & 20) 2012 measures 16,0 feet overall (2012), giving it roughly 4,0 additional feet of deck space compared to the Alumacraft Riveted Jon 1236 2011 at 12,0 feet (2011). Weight tells a clearer story for trailering families: the Alumacraft Riveted Jon 1648 (15 & 20) 2012 tips the scales at 285 lbs — 160 lbs less than the Alumacraft Riveted Jon 1236 2011 at 125 lbs. That difference is meaningful if you're working within a half-ton or three-quarter-ton truck's tow rating, especially once you factor in a motor, gear, and fuel.
Both boats share a closely matched power ceiling — 15 hp for the Alumacraft Riveted Jon 1236 2011 and 30 hp for the Alumacraft Riveted Jon 1648 (15 & 20) 2012. Real-world performance will come down more to which motor is actually bolted on, its load at the time, and whether it's a 4-stroke or 2-stroke setup.
For family outings this is probably the sharpest distinction between the two. The Alumacraft Riveted Jon 1648 (15 & 20) 2012 is rated for 5 passengers, while the Alumacraft Riveted Jon 1236 2011 caps at 3. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Alumacraft Riveted Jon 1648 (15 & 20) 2012 could be the deciding factor.
At this size, power-to-weight ratio matters more than outright horsepower. The Alumacraft Riveted Jon 1236 2011 comes in at 8 lbs per hp versus 10 lbs per hp for the Alumacraft Riveted Jon 1648 (15 & 20) 2012. The lower the ratio the more explosive the acceleration — meaningful on a short RIB where bursts of speed, quick planing, and agility in surf or tight waterways define the experience.
Bottom line: Choose the Alumacraft Riveted Jon 1648 (15 & 20) 2012 if your priority is putting more people on the water — it handles 5 passengers and at 16,0 ft it has the deck room to back that rating up comfortably. The Alumacraft Riveted Jon 1236 2011 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 3 that costs less to run day-to-day.