What causes bow waves when sprinting? Is it that the boat is reaching full hull speed? A high rocker? etc

I had the BB when we paddled out to Eastern Egg Rock one time. I sold it about 3 years ago because I couldn’t get the cockpit comfortable anymore, no matter what I tried. Only got $500 for it, because they’re not “Chic” anymore, at least around here. Very happy with just the 'Bou and the Anas. Judith’s Silhouette was a temptation every so often, but it’s outfitted for her and I’m a bit bigger than I used to be. But if she ever decides she doesn’t want to paddle it anymore…

Silhouette is still a very nice boat. Speaking of Eastern Egg, got out there with puffins still in the water last July. First time in a few years. Well worth the dogged long paddle back, Ma Nature decided to skip the afternoon wind part and go dead flat.

I backed it up with facts that shouldn’t be a problem. To me better than just saying I do not believe. It is a discussion forum correct?

OK, here’s my point - those speeds were “Top Speeds” recorded by the GPS, which means they could have been for 5 feet. You are talking about average racing speeds, which is a huge difference. I also use a GPS cycling, and on a long steep hill it can accurately record 45 mph as a top speed, which would only be for a few seconds going down a hill. No real effect on the 14 MPH average speed over the 30 miles I rode. GPS records both. In a distance racing situation, 14 is the only number that matters. I was talking about top speeds recorded by a GPS in a short all-out sprint. Nothing more than to show that different hulls have different points where they climb their own bow wakes.

I’m talking about a two hundred yard sprint with professional racers. The hull is not capable of 13 MPH even for a nano second without super currents and or wind.

My GPS says high numbers at times too. They are not real.

World record is about 13 mph or 21 kph

K1 200m flat water paddling world record belongs to Mark De Jonge and is slightly above 33 seconds, which makes the average speed of 21 km/h. Taking into account that they accelerate from zero, at some point the speed must be higher than 21 km/h to get this average, but not much higher.

Take into account that these speeds are reached by the strongest sprinters in the world and the 500m record is 95,5 seconds, with the average speed dropping to 19 kph

I took the above off another forum.

Far cry from a Caribou or my Nomad

1 Like

The actual kayak speed record is 19.2 MPH. It was done with a kayak that had hydrofoils on it, so it has nothing to do with bow waves.

In truth; actual paddling has little to do with all of the stats about what a hull can do. Those calculations are from fluid dynamics and mean little in the real world. Hull design, cockpit placement and paddle type are not heavily studied.

Racing boats have the cockpit much further forward than rec kayaks. They react to bow waves differently than fluid dynamics can state. The whole reason for specific rules is to find a way to bend them, or take them to places the rule writers didn’t foresee.

This discussion started around a Romany paddling with Valley boats, and I would not be surprised if the specific one mentioned was an older Aquanaut. Issue of a given GPS’s reliability is probably best assessed when someone is present when said GPS is being used.

One question was whether the rocker causes the water to peel off the bow differently than in the other boat. Given the post that the equation involved the length of the hull in the water, seems to me the answer is yes? Since the Romany is a foot shorter and the rocker further diminishes the length of hill in the water?

The other part was an observation that the longer Valley boat does not have the same phenomenon. Meaning the bow wake at the same speed where the Romany sets one up? Suggests this goes back to length in the water - the greater length means that when the Romany is starting to do that the 17’ long Valley boat would not yet be at that point. Regardless of paddler weight being at the higher end.