Previously top speed on my jetski was consistently 49-51. Last weekend I Rejex'd the hull and top speed is now 51-53.
I assume other waxes would be comparable, but this is the first one I've tried.
Its Yamaha XL800. 3 seater, 120 hp.
A friend of mine saw this on your board and asked me to comment as the RejeX / boating specialist.
Although there has been some debate on the subject, the general consensus is that a smoother surface equates to less drag and therefore higher speeds. Other wax-type coatings (especially Teflon fortified, a.k.a. PTFE) create a smoother wetted surface thereby increasing speed to some extent. But usually it's not enough of a difference to be noticeable.
With RejeX, the effect can be pretty obvious. Early on, we received numerous reports from jetskiers who noted that their jetskis came "out of the hole" (i.e. planed) faster. RejeX's ultra-slick protective coating has become very popular among offshore powerboat racers who pick up about 2-3% on the top end as verified by GPS (this has been well documented in several boating magazines).
Recently, a friend of mine coated his J/80 performance sailboat with 3 coats of RejeX. He went on to win this year's North American championship by such a wide margin that they didn't even have to sail the last day of a regatta. He said Tiamo (the name of the boat) easily had 1/10th, maybe even 2/10ths of a knot on the entire fleet – that's a world of difference at that level of competition where any tiny advantage can mean the difference between first and last. He also noted that the boat was bone dry by the time the trailer came out of the water.
RejeX's slickness is a byproduct of its primary purpose, which is to protect surfaces and "reject" stains. The reason it makes a jet ski go faster is the same reason why it inhibits bird droppings and bug splats from sticking to your car and keeps brake dust from adhering to you wheels.
If you have any questions, I'd be happy to answer them at [email protected]