Choosing a kayak
Introduction
The River Canoe Club (RCC) participates in a wide range of paddling activities on rivers, lakes, estuaries and the ocean. The club has an active whitewater group, but it is fair to say that most club paddles are medium distance (20-25km) and undertaken at a moderate average pace of 6-7km/hr on flat water, in mild river/tidal flows, in choppy waters and small swell and surf. This guide provides advice to people wishing to participate in these general paddles and not specialist paddles such as whitewater. The joy of paddling with the RCC is that paddles are social; we aren’t racing or out for a workout. Instead, we paddle together as a group, chat and enjoy our surroundings.
Before purchasing a kayak, you should think carefully about the type of kayaking you wish to do, seek advice and if possible, try out various kayaks to help you decide which is right for you. The club has a variety of boats you could paddle before buying your own plus knowledgeable paddlers to guide you. Don’t rush and consider perhaps buying a nice paddle or PFD/life jacket first as these make a huge difference to your enjoyment in the sport.
For group paddling it’s best that people paddle at roughly the same speed. Once you have a good paddling technique your kayak design is very influential. Put simply, if we paddle in similar boats we tend to have similar performance regardless of our individual paddling skill. That’s good for everyone’s enjoyment and safety.
As well as speed there are some other performance characteristics you need to think about to suite the club environment. Stability is important. Primary stability is about how stable the boat is at rest and secondary stability is about how stable the boat is at speed. Resting during club paddles is common either to let paddlers re-group, to take in the scenery, to drink and eat or even to perform a rescue. Therefore, you will need a kayak with enough primary stability for your skill level.
The final performance characteristic worth mentioning is manoeuvrability. You will need a boat that can turn and negotiate bends in the river, obstacles and can be controlled in currents and surf.
People new to paddling often ask for advice on what kayak to buy. This webpage is intended to assist this decision by explaining certain design concepts and principles. Ultimately your choice of kayak is going to come down to a compromise between various performance impacting features including how easy it is to carry the boat to and from the water. It’s important for you to understand that your choice of boat may limit the paddles you can join.
Kayak Length
Most people in the club paddle a sea kayak of between 4.8m and 5.3m in length. A few people paddle boats a little shorter or longer. It is rare for people to paddle a boat less than 4.3m and despite any marketing you may read, boats less than 4.3m are recreational boats rather than a sea kayak.
The length of a boat is arguably its most important aspect. Speed and length are closely related. The longer the kayak the more energy can be built up between strokes and this increases speed and reduces effort so a long boat can usually be paddled faster and further with less effort. If you look at the wake of a short river boat compared to a sea kayak you will see that the river boat rises and falls and turns, producing energy sapping waves compared to a sea kayak that slices through the water with little wake.
Length also improves tracking (paddling in a straight line) and reduces manoeuvrability (turning) making a long boat better suited for distance paddling.
Shorter boats are generally better to control in waves due to a shorter waterline and an increased “rocker” (see below).
If you choose a boat less than 4.8m you will need to work harder to keep up with most club paddlers. You may not be able to join all club paddles, especially longer paddles, paddles where the speed needs to be higher, or paddles where the conditions are more demanding (chop and swell).
Width or Beam
Wider kayaks tend to have more primary stability (stability at low speed or when still) and are popular with beginners for this reason. The drawback is that they must push more water to the side which takes extra energy, reduces speed and increases the paddling effort to cover a distance.
By contrast narrower boats are faster but have less primary stability. This needs to be considered in the club paddling environment where stops are common to let the paddling group regroup or take-in the surroundings.
Popular sea kayaks used by members are typically have a beam of 55cm to 62cm. The boats around 55cm beam tend to be high performance kayaks whereas those 60cm or wider are more likely to be favoured by members new to kayaking.
Rocker
The rocker is the longitudinal upward curve along the very bottom of the hull and it is very influential to manoeuvrability. It is the measurement from the base of the bow or stern to the very bottom of the boat. It also helps to determine the waterline (the length of the hull in the water). A boat with very little rocker helps with the speed and tracking to keep it in a straight line. The more pronounced the curve (the bigger the rocker) the more manoeuvrable the boat will be but it will also be a bit harder to keep tracking in a straight line. You will need some degree of rocker but there are other aspects that also affect the boats manoeuvrability particularly the hull cross section.
Hull Design
The hull is the portion of a kayak below the deck line. The shape of the hull in the water has a pronounced effect on the speed, stability and manoeuvrability of a kayak. Below is a broad description of hull designs and their characteristics. In practice, most kayaks are a combination. For example, most sea kayaks have a very pronounced v-shaped bow and stern that transitions into a rounded, slightly “v” shaped or flat hull towards the mid-point.
Round
A rounded hull is common on narrow boats and allows them to cut through the water better. It tends to reduce primary stability and is more common in kayaks designed to travel distance offshore. Round shaped hulls tend to be more stable at speed. Surf Skis are good examples.
The lack of primary stability needs to be considered in the River Canoe Club paddling situations as there are times when the group will be slow or stationary in the water and therefore a round hulled boat is less stable and more prone to capsize especially with paddlers new to the sport.
Flat Hulls
Flat hulls tend to have good primary stability and ride on top of the water. They are often wide and can be good in surf. They tend to have lower performance in terms of speed and endurance than round or V-shaped hulls.
V-Shaped
V-shaped hulls cut through water well and provide good tracking (maintaining a straight line). This makes them good for distance paddling. They have better secondary stability than primary stability compared to a flat bottom hull. Many sea kayaks feature a shallow “V” shaped hull to provide a compromise between a flat bottom and a more aggressive “V’ shape.
Pontoon Hulls (not illustrated)
A Pontoon hull is popular on many fishing kayaks. It is like a flat bottom hull but has a raised profile running along the centre line so that the boat sits in the water on two outer tubes. These hulls are usually wide across the beam. This helps greatly with stability and in calm water it may be possible to stand upright to fish. However, these hulls produce a large drag in the water, making them slow and taking more effort to paddle. Boats with a pontoon hull not suitable for club paddling.
Chine
The chine is the term given to transition between the bottom of the hull and the side of the hull (see diagram above). Generally, a more rounded (softer) chine helps with secondary stability but reduces primary stability. A harder, more pronounced chine can also aid tracking but in currents and surf, a hard chine may also catch and make the kayak harder to control. Most sea kayaks have a soft chine but there can be exceptions, an example being a wooden kayak made from plywood. A soft chine is particularly useful on the “edge”. Edging a boat is when a paddler tilts a boat to one side whilst keeping their body over the centreline of the boat to avoid capsizing, i.e. the paddler is not leaning to one side, but the boat is no longer flat on the water. When edging is performed the hull profile engaging with the water changes to become more rounded with an increased rocker. This shape makes the boat more manoeuvrable without introducing drag from a rudder. Utilising the edge is a favoured method of turning and can also help maintain direction in gentle cross wind and waves.
Bulkheads and Storage
A sea kayak will normally come with two or three bulkheads. One will be in front of the feet and any others behind the seat. These have “watertight” hatch covers on the decks allowing items to be stored inside and kept dry. In practice very few, hatches are completely watertight especially if the boat has capsized.
Bulkheads are very useful for storing items, especially on long day trips and overnight camping. With the right gear you should be able to store everything you need for several days inside a sea kayak including lightweight camping gear. Anything stored inside a hatch that can be water damaged should be inside a watertight container such as a dry bag.
Storage aside, a bulkhead and dry storage is a primary safety feature of a sea kayak. This is because it stops the boat becoming completely flooded in a capsize, keeping the boat afloat and allowing deep water rescues to be performed. If a boat doesn’t have bulkheads, or just has a rear bulkhead, airbags should be fitted to prevent the complete flooding of the cockpit/seating compartment.
Rudders and Skegs
Most sea kayaks are fitted with either a rudder or a skeg that can be lowered into the water from the cockpit using a pully. In the case of a rudder this can then be swivelled from side to side to turn a boat. A skeg is a flat blade that is lowered from the bottom of a kayak but cannot be swivelled. Therefore, a skeg will simply help the boat to track in a straight line. Rudders and skegs are not necessary to steer a boat and it is preferable if these are not used routinely. Their main purpose is to compensate for conditions such as a cross wind or waves coming from the side or behind (a following sea). Normal manoeuvring is best achieved by paddle strokes and engaging the edge (see section on Chines above). A rudder will also add drag to a boat and slow it down. Rudders and skegs can be a hindrance in certain situations such as manoeuvring in flowing water or paddling through surf. As rudders and skegs rely on pulleys and levers which are prone to breakage, the River Canoe Club likes paddlers to have the skills to manoeuvre a boat without the use of a rudder or skeg.
Weight
The weight of a kayak will be determined by the construction materials, its size and shape and any outfitting (seats, hatches, rudder/skeg, bilge pumps, etc). Weight is important for two reasons.
On-water performance of heavy boats tend to slower and require more paddling effort than a light boat. Imagine two identically shaped boats, one made of plastic and weighing 28kg and the other made from a Kevlar composite and weighing 18kg. The heavy plastic boat will sit a little lower in the water than the composite boat. Whilst this causes a marginal increase to the waterline length, it has more influential effect on the waterline width, increasing drag exerted on the boat, slowing it down and requiring more effort from the paddler.
The other important factor is handling on dry land. Kayaks can be heavy and are awkward to carry. They generally need to be lifted onto a cars roof rack, and it is normal to have to carry the boat to and from the car either at home or to the launch spot. Wind can also catch a kayak making it more difficult to carry especially when tired after a paddle. There are lifting aids and trolleys available to purchase that can help but you need to consider your physical ability to move a kayak yourself. Note: at club paddles people are encouraged to help each other carry boats to and from vehicles and the water.
Construction Material
There are many construction materials that can used to make a kayak. The main groups are described below.
Roto Moulded Polyethylene Kayaks
Very popular with beginners, these kayaks are formed by melting beads of plastic into liquid form in a hollow mould within an oven. The mould is rotated until it covers the entire inner surface to a thickness of typically 3-5mm and then cooled. The solidified kayak is then removed from the mould, trimmed and outfitting fitted.
Made well these boats are very robust, can handle rough treatment (although they are not indestructible), and require minimal maintenance. They are however heavy compared to alternatives. Due to the construction methods roto-moulded boats are both inexpensive and readily available.
Whilst a well-made boat will be UV stabilised, they are best stored away from sunlight whenever possible. In very hot, sunny, conditions they can also warp and buckle if left in the sun, including when on a car roof rack.
Thermoform Kayaks
These are plastic boats made from sheets of plastic that are heated and vacuum formed on the inside of a mould. The sheets of plastic may have multiple layers of different materials. The boats are made in two halves (hull and deck) and later joined.
These boats offer many similar qualities to roto-moulded boats but are lighter and have a “quality feel” close to composite boats. They have good strength but are not as robust as a good roto-moulded boat. The UV resistance is often restricted to the outer layer or plastic so the inside of the cockpit and hatches needs to be kept out of direct sunlight when not in use. These plastics can also become brittle in very cold climates.
The cost of these boats is typically between that of a roto-moulded boat and a composite boat.
Composite Kayaks
Composite kayaks are made from several layers of fibreglass, polyester, aramid (Kevlar) or Carbon fibre or a combination of these. The fabric layers are laid in a mould and soaked with a resin that cures to form a strong, watertight structure. Some composites can also include special layers such as honeycomb to add lightweight strength. The fabric material can be expensive (particularly aramid and carbon fibre) and the boats are labour intensive to build making them expensive to buy. A significant proportion of the weight in a composite boat is from the resin used to soak and stiffen the composite cloth once the resin has cured. Traditional construction methods apply resin with a brush or roller. Many manufacturers now use a vacuum bagging system to apply resin. Vacuum bagging uses less resin and pulls the fibre layers together tightly to produce a higher strength and lighter kayak. A coloured “gel-coat” is applied by many manufactures to the outer surfaces of a kayak to provide a high quality finish. Compared with a plastic boat, composite kayaks require more care and maintenance.
Fibreglass – This is the original composite material and is the cheapest. Originally fibreglass was provided in chopped randomly spaced strands, but it is now more common to use a woven mat. Fibreglass is transparent and therefore a colour pigment is usually added.
Aramid Fibre – This woven fibre is commonly known as Kevlar (a trade name). It is similar in strength to fibreglass but is stiffer, lighter and more expensive. It is tougher than carbon fibre. Aramid is usually a yellow colour but recently has become available in other colours. In kayak construction it is often woven with carbon fibre to further increase stiffness and strength whilst retaining toughness. Kevlar/carbon fabric usually has a yellow and black checkered appearance which is often made a feature of the kayak design.
Carbon Fibre – This is the lightest composite fibre and is also the most expensive. Whilst it is strong and stiff it is more brittle and cracks easily if impacted. Carbon Fibre is often the first choice for competition boats but is less common in recreational or sea kayaks. In recreational boats and sea kayaks it is often woven with aramid fibre (see above)
Composite kayaks are the best performing kayaks in most situations. However, they are much less impact resistant and rocks close to shore or in rivers need to be avoided. If paddling in a flowing river with rocks or rock-hoping on a coastal shore, plastic boats are a better option.
Wooden Kayaks
Wooden kayaks are not generally available commercially as the amount of labour needed to construct one makes commercial manufacturing unviable. Instead, they are handmade by enthusiasts usually at home. Wooden kayaks are both individual and unique. As these are “home-made” they can also be built for little more than price you would pay for a good roto-moulded kayak. You would however have to put aside 300 hours or more to make one. They come up on second-hand markets from time to time, often at reasonable prices.
Wooden kayaks are effectively composite kayaks as the wooden boat is encased, inside and out, in a layer of transparent fibreglass. This makes the kayak very strong and, as the wood used is low density, a finished sea kayak is often a comparable weight to a high-class composite kayak (perhaps 19-21kg). If considering making or purchasing a wooden boat be prepared to do periodic maintenance to keep it in good condition.
Inflatable Kayaks
There are a range of inflatable kayaks available. They offer some advantages for storage and transportation, however, with few exceptions, most are not suitable for club paddles. Even high-quality inflatable kayaks will struggle to achieve the required performance needed for club paddles.
New or used?
Purchasing new has the advantage of being able to get precisely what you want within any budget constraints you may have. It’s a great feeling putting your new boat in the water for the first time and going for a paddle. However, if you are new to paddling, building your capability, or have budget constraints, there is a good second-hand market for kayaks. Whilst you may have to compromise on your ideal boat, it is possible to pick up bargains which, if you look after it, can be sold later for a similar price to what you have paid. This gives you an opportunity to inexpensively transition to more advanced boats as you develop your paddling ability. It is also quite possible to buy a high-end composite kayak on the second-hand market for the price you would spend on a new roto-moulded kayak.
Summary
Due to the need to paddle at similar speeds, paddlers in the club are best to use similar boats. Club paddlers typically paddle a sea kayak of around 5m in length and with a beam of 55-62cm. Most have a soft chine on a shallow V hull. Most have rudders or skegs fitted. All sea kayaks have watertight bulkheads and hatches in front of the feet and behind the seat.
The club has a fleet of kayaks that can be used by members. These have different characteristics that can help you decide what to buy. The club also has experienced paddlers that can provide advice. Don’t rush to buy before you know enough to determine your needs. Have fun in your paddling journey.