Da una ricerca sul web ho scoperto che il dubbio da me manifestato è lo stesso che ha originato questo articolo sul sito dell'Associazione proprietari di barche USA:
Who Needs A Transom Savers?
By Scott Henze
Some boatbuilders think they’re vital, while others are offended at the idea
Are transom savers essential protection for your boat and motor, or simply snake oil designed to drain an extra nickel from you? It depends on whom you talk to.
My assumption before writing this article was that they are, at the very least, a good idea if not a requirement.
In some cases, this is true. The deeper I delved into this, however, I discovered that isn’t necessarily so.
Getting to Yes and No
Its name would imply that the transom saver is a device designed to protect your boat’s transom from undue stress while trailering your boat. A common argument against the need for one of these is that the forces exerted upon your transom during typical boating conditions greatly exceeds those encountered while trailering. To clarify this point of contention, I went directly to the source and contacted several major boat manufacturers to get the official company line and was surprised by what I found. Not only did the majority of the boatbuilders I contacted dismiss the need for a transom saver, but a couple of them seemed to almost be offended by my calling into question the structural integrity of their hull. As one tech put it, "You will be hard-pressed to find any builder willing to admit that their transom isn’t strong enough to handle the load," and he was right. Tracker Boats, on the other hand, endorses their use and includes a "motor toter" with all of their packages. These findings fall in line with the general notion that smaller jonboats and bass boats are more susceptible to transom damage due to their higher motor-to-boat weight ratio. Aluminum boats also seem to be more prone to damage (broken welds, popped rivets) than heavier, reinforced fiberglass transoms.
Ranger Boats is another transom saver advocate. “There is a great deal of impact on the transom while traveling down the highway,” notes Ranger’s Trailer Engineer Rick Huddleston, "and a transom saver [connected to the rear cross member of the trailer] is far more effective at preventing stress at the engine bracket and transom than using the 'tilt/lock' feature on many outboard motors."
Indeed, many outboards trailered across the country are set in the "up"position and held in place only by the powertrain tilt/lift system support. Advocates of this idea point to the fact that the weight of the powerhead is shifted forward so the transom actually is used as a fulcrum of sorts. It may work but one must remember the power tilt on an outboard was never designed to support the engine for trips over potholes and dirt roads, other than to lift it when in shallow water or when leaving the boat ramp.
Mercury, for example, recommends trailering with the motor in the full vertical position, and no additional support is required. If this is not possible due to limited ground clearance, additional support is recommended. Newer Evinrudes, on the other hand, have a built-in spring-loaded support that completely eliminates the need for an aftermarket product. One universal word of caution is that the outboard’s tilt bracket is designed to support the motor during maintenance or storage only and should never be used when trailering.
Variations on a Theme
Without a transom saver, a skeg (center) can hit the pavement. Evinrude outboards use a lock arm (right) instead of a traditional transom saver (left) that attaches to the trailer frame and outboard.
If you decide that a transom saver is right for your situation, there are several different options from which to choose. The most common type is essentially a bar that extends from your outdrive to your trailer, such as those offered by Swivl-EZE and West Marine, available with either a fixed shaft or one that is spring loaded to help absorb some of the road shock. The motor end has a “V” that the outdrive rests in and the trailer end has either a “U” that fits over the rear roller or a pin which affixes directly to the trailer frame. If your outboard is equipped with hydraulic tilt and/or trim, it should be lowered so that there is enough pressure to hold the bar in place. If you do not have hydraulics, the transom saver must be securely fastened at both ends with a strap or bungee cord to ensure that it doesn’t pop out as the motor bounces around.
Another option is a rigid tube that installs directly over the trim rams such as T-H Marine’s Motor Stick, the M-Y Wedge, and Yamaha’s Outboard Trailering Support. These products are easy to use and are very small (only a few inches long) and easy to store when not in use. To install these devices, simply trim the outboard up, slide the wedge over the tilt rod, and trim the outboard down until it’s snug. This is obviously not an option for motors without hydraulics. A variation of this "wedge" type of product is the Lock-n-Haul. "If the motor is moving up and down diagonally on the tilt pivot, then a trailer support like the traditional transom saver makes more sense," observes Jim Smith of Lock-n-Haul. "But since most boats have a power tilt system that doesn’t let that happen and transoms that are rated for particular outboard sizes, the 'trailer tether' is effectively obsolete."
Rather than sliding over the trim ram, the Lock-n-Haul consists of a pair of aircraft aluminum rods that wedge between the motor’s lower unit and the mounting bracket. Again, power tilt is required with this system. Some opponents of these different wedge types argue that while they may offer some protection for the outboard, they do not take any of the strain off the transom. In light of the fact that Grady White, Chris-Craft, Boston Whaler, to name a few, neither require nor recommend a transom saver for their boats, this seems like a rather moot argument.
Still, as inexpensive as they are, they’re cheap insurance. Better to have one and not need it than to need it and not have it, right? Or do they do more harm than good as the detractors allege? I was actually surprised at the amount of negative feedback I found. The most prevalent argument against them centers on the fact that a transom saver transfers the weight and energy from an area that is designed to handle it (the transom) to an area that is not (the trailer). Additionally, while the boat and motor move together, the boat and trailer move independently from each other, causing road vibrations to be transferred back to the outdrive where they can potentially cause even more damage.
As always, there are a variety of different scenarios and what may be right for the next guy may not be right for you. In general, I found that smaller boats and trailering situations where there is limited clearance between the outdrive and the ground benefit the most from the use of a transom saver. The best advice is to follow the recommendations from your boat and motor manufacturer.
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