Recently, I was chatting to a mate trying to convince him to take up kayak fishing and was talking about my limited understanding of needing a longer yak in the bay vs in a lake / river and he asked whether having a pedal drive would negate the need for a longer kayak in the bay to combat wind picking up, getting tired etc..

I didn't know the answer.

Any advice?

Others might best answer this for you but i will add my 2 cent worth. The length of a kayak does many things but the 2 main reasons for the length are weight carrying capacity and tracking (traveling in a straight line while paddling) then from a safety point of view a longer kayak can withstand rougher conditions, many people will give you stories off being out on the water when conditions change unexpectedly and without warning, i for one have been caught out on a few occasions

When i first started i bought a cheap secondhand shorter yaks, although it was perfect for what i bought it for it was only a month later before i upgraded to a 4m yak, i had never taken the small yak into ppb only sheltered waters (swan bay) this new yak allowed me to paddle out to the channel 3km each way and it even went offshore on a few occasions.

Whether you afe paddling or pedalling it doesn't matter size does matter, you will also use less energy in a 4m yak than in those short ones

I thought the hull speed of a kayak (the thing that makes longer yaks go faster) was going to be the same irrespective of the mode of propulsion

A peddel drive won't make up for having a shorter yak. Yes paddling a shorter yak is very difficult and can be dangerous in rough conditions. A pedal drive can help with maintaining momentum into wind but there are numerous other factors to consider when its rough. One of the main ones is being able to deal with following waves or waves from the side. A short yak, even pedal can be more easily turned by these waves leading to an unsafe situation where you can get separated from the yak. If they want to handle rougher conditions safely on the bay they will need a longer yak (eg ~13ft+).

For bays I think a medium length yak around 3.8/4m is ideal, like my Outback.

These should be long enough to track well and have a rudder.

I've been anchored up with mates on those Ferarri like 5.5m+ Stealths and they often find that they are sitting in the middle of a wave as the wave crest passes the middle of their yaks while my Outback just bobs over the top.

5.5m might be overkill for the bays, but don't go for the little 2.9m things the plonkers on facebook constantly recommend

thelastreject wrote:Recently, I was chatting to a mate trying to convince him to take up kayak fishing and was talking about my limited understanding of needing a longer yak in the bay vs in a lake / river and he asked whether having a pedal drive would negate the need for a longer kayak in the bay to combat wind picking up, getting tired etc..

I didn't know the answer.

Any advice?

there are a lot of variables to consider Shane pointed out

shane wrote: One of the main ones is being able to deal with following waves or waves from the side. A short yak, even pedal can be more easily turned by these waves leading to an unsafe situation where you can get separated from the yak. If they want to handle rougher conditions safely on the bay they will need a longer yak (eg ~13ft+).

following seas with a long kayak the boat wants to track so it's both easier to hold a heading and to keep up speed - using a pedal kayak in these conditions you don't have a paddle in hand - so if the rudder comes out of the water these can turn side ways and you dont have a paddle in hand to brace or correct with

longer kayaks tend to be narrower as well this cuts down drag and the longer hull length increases hull speed ( of cause you have to be strong / fit enough to paddle at higher speeds to to match the hull speed ) and of cause a longer craft will wont to track better also helping with higher speed

so why is more speed desirable on a bay or open water kayak - think of it this way a long ski like a stealth ( or other brands ) over 5 meter long will normally cruse around 8 kph with a fit paddler - a 3 meter kayak will cruse around 3 kph
put both of these boats into a 10 knot head wind - the 5 meter ski will still do 6 kph but the 3 meter fishing kayak will be struggling to make head way

now get caught out with a 15 knot head wind

try the same thing down wind many short kayaks will wont to turn around due to poor tracking - where as a 5+ meter fishing with a 15 knot tail wind you are catching runners and surfing in

next thing side on waves short kayaks are normally quite wide to pick up primary stability side on to a wave these boat wont to stay level to that wave no matter what the angle of the wave is - a narrower kayak like a 5 meter ski is easy to stay upright on the face of a wave because the primary stability is lower

these are basically giving 2 ends of the spectrum but you will find that most seasoned kayak fishos will steer you to an around 4 meter kayak for the bays --- again most kayaks around this length 4 M have good tracing - good speed - a fair amount of room and storage

but back to what I said there are a lot of variables in kayak design

Just go the AI and have the best of everything.

maverick wrote:Just go the AI and have the best of everything.

x2

maverick wrote:Just go the AI and have the best of everything.

Is this why the AI is your only Kayak Mav?



Cheater summed it up very well. The only thing I would add is that when you transition from plastic to fibreglass kayak (which will inherently see you going to a longer kayak) you will typically also save a fair amount of weight.
My Hobie Revo 13 (4.1m) was 40-42kg rigged and
My Stealth Profisha 525 (5.25m) is 26-28kg rigged

Storage and transport for longer kayaks do also tend to cause issues over 4ish metres long