SEA JAY 485 HAVEN & NEW YAMAHA F70

Sea Jay’s side console 485 Haven and Yamaha’s latest 70hp 4 stroke are a mightily attractive combination, regardless of whether you’re Top End barra bum, an impoundment bass bumbler or southern bream bum freezer.

From several viewpoints it’s a good thing that the Sea Jay 485 Haven, powered by one of Yamaha’s latest 70hp 4 strokes, comes up for a test in the same issue as the Stacer Nomad featured nearby. To begin with, 
Sea Jay’s Haven is an excellent example of the industrial-strength tinnies so (deservedly) popular in the north. That, and it being yet another contemporary development of the ever-popular Top Ender style, do however pale somewhat beside the glow of the outboard powering it.
By some way the lightest 70hp 4-stroke we’ve seen (at just 15 kg heavier than its classic 3 cylinder 2-stroke), Yamaha’s new 4-stroke 70, designated F70, may well be the most significant new outboard so far this century. It’s a whopping 18kg lighter than Mercury’s classic 75hp 2-stroke, for example, so, unfair though it may well be to a darn good boat like the Sea Jay, we simply must devote a suitable amount of attention to the motor powering it.

But first things first: the Sea Jay 485 Haven. Having been critical of the basically 
ready-to-go-fishing Stacer for not providing any means of stowing the 2 or 3 or more rods we expect to take fishing (apart from some side-deck rod holders which, as I said elsewhere, are to my mind more holders for use while fishing, than a place to keep rods safely out of the way) the same comments must be made about this Sea Jay.

I’m not going to back away from these sentiments because I think it’s fair comment. Having said that though, Stacer packages its boats ex-factory pretty completely, including things like a factory trailer, a sounder, a VHF radio and a live-bait tank as standard fitment with an options list including little more than the shade top seen on the other test boat; whereas when you buy a Sea Jay the accessories inventory is left for you to work through with your dealer — or to organise after the initial purchase.

My point here is that many of us would actually prefer things this way. For some, choice of a trailer and sounder, for example, is a highly critical decision we’d prefer to make completely outside which boat and motor to buy. So while I may go on about test boats not having rod racks, I must also acknowledge that some people (myself included I admit) prefer a very well built if somewhat more basic boat like this one and proceed from there to set it up to suit myself. This can be done with Stacers too if you prefer; talk to your dealer about it…

Very well built describes Sea Jay boats in a few words, although one of their 2010 models is a far cry from the battered veteran Sea Jays you see so commonly in north Queensland driveways. One thing images in a magazine can portray accurately though is how a boat looks and I think you’ll agree this boat lacks absolutely nothing in this department…at all.

It’s a good-looking boat!

Sea Jay’s high standards of build quality are still there too and, if comparisons with the Stacer are unavoidable, the choice for you the interested potential buyer comes down to the differences between an internally-framed thinner skin construction and what is commonly, if erroneously known, as plate. Along with that, our Sea Jay is a generally beefier, higher-sided hull, featuring a more conservative (conventional is perhaps another applicable description) underwater shape.

Weighing 500 kilos, as opposed to the Stacer’s 415, is an indication of what beefier means. Some of this is due to plate construction adding weight; some to the higher sides etc.

The pros and cons of the two types of construction needn’t be debated here; suffice to say that Sea Jay’s 485 Haven with Its Ultimate Edge hull can be expected to deliver — and on the water it certainly does deliver everything you’d expect from a boat of its genre; albeit a notably well-built, and well-finished version of the genre with a contemporary hull design developed to a point where it sits amongst the leaders there…
Inside, this boat follows the same formula as our other test boat this issue. It has a raised casting deck in the bows and a full depth cockpit and aft bulkhead. There’s a side console obviously meant to suit seated driving and a pair of comfortable bucket seats with a choice of positioning sockets.
Roomy side pockets along each side of the cockpit do protrude past the side decks enough for your leg to encounter them before the support of the side decks is reached. If you fish open rough water enough for this to be a negative point, it’s possibly worth noting; although I’d suggest that most people looking at a Top Ender-type boat will be happier with the loose gear the side pockets can swallow than they’ll be upset about their intrusion into cockpit space.

Our test boat had a mounting pad for an electric on the bows and a 60 litre fuel tank hidden away below decks with its filler up on the side deck and a pair of breathers outboard on the transom where they all belong. A grab bar over a smoked acrylic windscreen and low bar work on the bows and aft end of the side decks are all useful fitments.

Looks are important these days and, if we’re already agreed the 485 Haven is a good looker, there’s no argument with a two-tone paint job sensibly omitted from the hull’s bottom where it’ll only end up looking crappy if painted anyway. Practical as well as pretty, there’s everything to like about Sea Jay’s 485 Haven. It’s a fine piece of work.

Yamaha F70
Our test boat’s hull is specified for motors up to 80hp weighing up to 180kg so our 70hp 120kg Yammie is well inside that. With 60kg up it’s sleeve and 10hp less than the max the hull/motor combination is rated for, it’s nonetheless a very nicely-balanced package. On the water, it trims out beautifully, staying nice and flat across chop and maintaining the kind of agility you need for hard turns around river bends and low tide channels.
Swinging a 15-inch-pitch prop, with only safety gear and 2 adults aboard on 
lightly-ruffled water, the top speed was a couple of decimal points under 61kph, or nearly 33 knots if you prefer, at 6300rpm. This may not be enough for Top Enders (people, this is; not boats,) facing long runs on big rivers like the Daly who might look at going to the max in power choices.

More importantly for others who don’t need to fly 60kph plus downriver to fish are the new F70’s cruising speeds on our Sea Jay test boat of 30kph at 3500rpm and 35kph at 4000rpm really come into focus when related against fuel consumption of 8 litres/hr at 3500rpm and 10 litres/hr at 4000rpm. People are talking kilometres per litre a lot these days, so let’s call it 3.6km per litre burned. At 5000 rpm and 46kph, the figures are 15 litres/hr and 3.1km per litre burned. Impressive!

At 996cc displacement, the F70 is a 
small-capacity motor compared to competitors, such as Suzuki’s 1502cc 70, and Honda’s 1496cc 70. The (fairly) heavy Sea Jay hull then is a good test of the new Yamaha’s mid-range 
torque delivery, torque which might be expected to be lacking in a smaller-capacity motor — but certainly isn’t if this test is any indication; which I’d suggest it clearly is. In fact, the F70’s torque spread across the entire rev range from sub-planing acceleration speeds right up to flying downriver as hard as you can go is one of its most impressive attributes.

The F70 is a 4 cylinder single overhead cam 4 valves per cylinder configuration so sits reasonably high on the transom. Visually, the sweeping silhouette of the powerhood doesn’t make it obvious. Our test Sea Jay’s transom arrangement handles the height without noticing it anyway.

When you consider how damn good the latest 70 (and 75hp) 4 and new-tech 
2-strokes are, the choice between 70(ish)hp motors just got a whole lot harder!

As a combination, Sea Jay’s side console 485 Haven and Yamaha’s latest 70hp 
4-stroke are a mightily attractive proposition for readers of this magazine.