Category Archives: Drop-Stitch Kayaks

The future of IKs

TPU Inflatable Kayaks: the Missing Link

Pictures from Zelgear and Marcin S

These days IK are mostly made from PVC, be it the hull or the bladders. Just three main IK brands still using old school synthetic rubber: Gumotex (CZ), Grabner (AT) and NRS (US). PVC gets recycled, is made everywhere and so is cheap off the roll and easy to heat weld. But is it only me who finds something unpleasantly ‘plasticy’ about PVC: the stiffness, the texture, the smell and maybe the eco-stigma.

The only PVC IK I’ve ever owned punctured on the slightest thorn and went on to do that with the next owner. And this was supposedly quality Mirasol PVC from Germany (to be fair, a mate with an older K40 had no puncture problems whatsoever). I can’t imagine any Gumotex or Grabner I’ve had ever doing that. That’s why I persevere with synthetic rubber IKs, even if I believe it’s becoming an expensive dinosaur fabric.

Synthetic rubber coatings like Nitrilon and EDPM are derived from the original DuPont hypalon. Boats must be entirely hand glued which adds to costs. But, in the same way nothing man-made has yet managed to beat the properties of leather for crashing fast motorbikes, compared to PVC, synthetic rubber remains more durable and more resistant to UV, lighter, more supple, easier to glue and easier fold compactly. After 15 years there was no noticeable deterioration in my Sunny, (below) other than a decade and a half of paddling wear and tear. A synthetic rubber IK will easily outlive a similar PVC IK.

Packrafts, meanwhile, are mostly made from TPU (as well as PVC), a different sort of polymer coating which has many of the benefits of synthetic rubber: odour-free, smooth texture, light, UV resistant, supple (crease-free), not environmentally toxic. But, like PVC, it too can be heat welded. Since Alpacka got the ball rolling, there are now loads of brands banging out TPU packrafts left, right and centre. In this time the fabric and seam technology have proved themselves to be as durable as PVC or rubber, and capable of running higher pressures. As someone on the internet observed: ‘Thermoplastic Polyurethane (TPU) is the link between rubber and plastic’.
For inflatables TPU is clearly superior to PVC in all ways except price. “It has properties between the characteristics of plastic and rubber. So, it is flexible without plasticizers, and its flexibility does not affect the design or its strength and durability.” Link

In a way, my 3-metre MRS Nomad packayak (above) was as much a TPU kayak as a packraft. With just 2psi or so, it was able to hold its shape (or my centralised weight), but now costs nearly €1400 in the decked version.

Zelgear TPU IK

While researching the Zelgear Spark 450 preview I found a 2018 ZelGear catalog. It states their now discontinued 5.2m PVC Igla IK can be requested in TPU (or the similar and much stronger Vectran which Alpacka use for their top-of-the-range packrafts). There’s more here. The weight of this long boat: is said to be just 15kg. The cost? $2000 I was told.

You may wonder if relatively thin and flexible packraft TPU could support a 5-m IK? TPU coating is also said to be more elastic than PVC, but it can’t be any more elastic than rubber. And anyway, a stretch-free scrim (woven core) takes care of that; the coating is primarily for impermeability.

An IK needs to be a lot more rigid than a relatively short and squidgy packraft. A lot of that is down to the fabric as well as the psi. That’s one good thing about inflated PVC: it’s stiff. You’d think a TPY IK would require high pressures to support a long boat which would then require bombproof seams. But add a drop-stitch floor (left) in TPU to take the load and the tubed sides would be under less pressure, so to speak. This Zelgear blog post from 2018 mentions some “some technological issues are being resolved“. I’m told Zelgear are on it.
Pictures below by Marcin S from a boat show in 2018.

With all these Asian-made TPU packrafts knocking about, some using locally sourced fabric whose quality – in my experience – is as good as the Alpacka stuff, the cost of TPU fabric may drop to a level matching the few ‘hypalon’ IKs still available.

A few years ago I predicted that full drop-stitch IKs would become the new thing. This has happened and has driven IK design and sales a long way forward . But, PVC aside, I’m still not convinced by the boxy profiles and packed bulk of FD-S IKs. Until FD-S forms can evolve (as the Itiwit X500 has shown), I think drop-stitch floors (D-SF) are certainly the way to go, if an IK is to stay undecked, unlike the X500.

There will always be a demand for cheap vinyl or PVC IKs but I predict the next big thing in high-end IKs will be TPU, including removable D-S floors in TPU. TPU is now well proven with packrafts and blends the heat-welding benefits of PVC with nearly all the better attributes of ‘hypalons’.

Tested: Tyre pump adaptor for inflatable kayaks

You may have seen these bayonet/car tyre adapters on eBay in recent months (left). The bayonet end clamps into your IK’s raft valve (won’t work on Boston valves). The other end is a regular Schrader valve like on your car/bike wheel. Attach that to your 12-volt Halfords tyre compressor and you can inflate your IK from your car battery. No more of that effortful, back-breaking pumping!

Me, I’ve never seen the value of electric pumps for IKs. You can only use them near a power source and how hard is inflating an IK with a good barrel pump anyway? It seems some think it is

The difference between tyres and IKs:
• a car tyre is a low volume running high pressure (~30 litres @ ~30psi)
• an IK has high volume but runs low pressure (3 chambers of 50–160 litres @ ~3psi). Drop-stitch has less volume but runs much more.

That’s up to five times more volume in an IK but at a tenth of the pressure. I would guess the swept volume of my better-than-average car pump (left) is 3–5cc. My Bravo RED 4 barrel pump is 2 x 2000cc (it pumps on the up and the down stroke).
Even if my 12-volt compressor whizzes along at 1001rpm, it will still take a long, long time to fill a 160-litre IK floor. But for a fiver, I thought I’d prove myself right.

The easiest way was to pump my Seawave’s floor to the point the PRV purged at about 3psi. The actual psi is immaterial but it’s consistant.

No surprise: it took less than a minute to pump up the 160-litre floor with the barrel. With my car tyre pump it took over 7 minutes.
And if you want say 4psi in the sides, or a 10psi drop-stitch boat, the duration of the tyre pump (or effort with the barrel pump) rises exponentially. It will take forever with the car pump adapter and I think the tyre pump would auto shut-off or burn-out before it reached anywhere near 10psi.

I read about portable USB rechargable electric pumps like the Pumteck or Sunta (left) on amazon from just £15. These are great for pool toys, air beds and other low-pressure items which just need a shape, not rigidity.
The Pumteck claims an obscure pressure rating of 4.5 kPa which sounds impressive but translates to just 0.65 psi or 0.045 bar. That is slackraft presure; there is no worthwhile IK that runs such a low psi, so all it will do is save you the easy initial pumping. For a typical 3-psi IK you’ll still need some sort of manual pump to top off and on a D-S IK, forget it. If your back can’t handle a barrel pump, get a Bravo foot pump.

Review: Aqua Marina Tomahawk Air-K 375 full drop-stitch kayak

See also:
Full Drop-Stitch IK Buying Guide

Andrew Cassely (guest reviewer)

I recently bought myself an Aqua Marina Tomahawk Air-K 375, after floating around on a cheap Bestway Hydro Force (right) over the summer. The choice was partly driven by availability – the Tomahawk was still on sale where others had sold out, perhaps because it was specifically listed as an intermediate to advanced kayak, while beginners are driving the shortage.

Overall I am pretty satisfied with the boat, though it’s not perfect. It comes in a fairly hefty package, but it is manageable for myself, an average fitness male. Smaller people and/or those with less strength may struggle a bit. The bag fits well and it technically a backpack. I wouldn’t want to go far with it but it works sufficiently well to get it out of the flat, down the stairs, and into the car.

Some work is required for set-up – the included pump is effective but needs some effort towards the end when approaching 10PSI. I may invest in an electric at some point. In fact the hardest bit is fitting the twin skegs: these are very stiff, and it’s difficult to apply pressure to the thin edge. I may need to take some sandpaper to get these to fit better, though I’ll try some silicone grease first. The seat and footrest are effective, a little strap threading is needed for the latter, nothing terrible. The seat straps keep their tension once set up, but the footrest doesn’t. Total setup time is about 20 mins, though that may reduce as I get more familiar with the kayak.

On the water it is a step change from the basic inflatable, though you’d expect that based on the price! It’s much faster, tracks amazingly well, and is a lot less tiring to paddle. The addition of an entry-level carbon fibre paddle provides a lot more range before fatigue sets in (though I still need to improve my stamina!). It turns relatively slowly to compensate, but I’ll take the better tracking any day.

I removed the front skeg to see if it would make it turn better. Turning was indeed a little easier, but the tracking was noticeably less effective (though still far better than the budget IK). In the end I decided I preferred both skegs, plus it’s reasonably heavy and right at the bottom of the boat and so provides a bit more stability.
It would work fine without through so it’s more a case of personal preference. It is noticeably tricky in the wind – because it’s relatively light, I’m slower in a headwind than a friend with a Point 65 sit-on-top. In crosswinds the high sides catch the air which makes stability less good in a gust.

It feels a lot less stable than the Bestway (I’m 77kg). I’m constantly working to balance it though I think more use will see that become less of a worry. Once or twice I’ve had a wobble and almost felt like I’ve gone over. However I think it’s actually a little better than it seemed. I deliberately flipped it to ensure I could re-enter and it took a lot more leaning over than I thought to capsize. It is probably not suitable for beginners whose balance is questionable, though. Re-entry was a little tricky put perfectly doable.

Packing up is reasonably quick – note that I do it with minimal drying on site, then re-inflate it fully once home to give it a proper wipe-down and time to dry. The drainage issue mentioned in the article is definitely evident: it’s basically impossible to get every last drop of water out, though I’d say no more than a tablespoonful was left which is not terrible. The joins between the floor and the sides also tend to attract sand and grit – the wipe-down gets rid of most, but I suspect at least a little is starting to build up there, though I don’t know how much of an issue this is in the long run as they shouldn’t rub against each other.

Despite the ‘Intermediate to advanced’ labelling, I think a beginner wanting to move on from an Intex or similar could do worse as long as they have at least a modicum of balance and confidence. I don’t think it would be for everyone though, as there are definitely more stable FDS kayaks out there. Overall I’m pretty pleased with with the Tomahawk, and hope the construction is good enough to provide many years of kayaking to come!

Drying your inflatable kayak

This video shows how to properly clean and dry a 3.8-metre Itiwit 2-3 seater, one of the most popular IKs of 2020 – or at least one which remained available when stock of so many others ran out.
It also shows the inner bladders and how they fit: something that’s rarely described on vendors’ websites.

Like so much Decathlon gear, their shell & bladder (S&B) IKs are a bargain. This orange Itiwit costs just £300, but the cleaning and drying process takes a while and realistically, is something best done over a couple of hours back home, if you have the space.
Quite rightly, after a sea paddle the owner was concerned about sand and other grit getting into the nooks and crannies around the floor, and even inside the sleeves which house the relatively fragile bladder ‘inner tubes’.

As it happens, the sidetube and removable floor sleeves plus their respective bladders (above) were merely wet inside. As on all IKs, the grit mostly settled down in the gutters inside where the floor joins the sides. This is why, with full drop-stitch (FD-S), drop-stitch floor (D-SF), or S&B IKs like this Itiwit, a removable floor makes proper rinsing, cleaning and drying so much easier.

Tubeless IKs like vinyl ultra-cheapies, most PVC Sea Eagles and IKs made from synthetic rubber, like the old Gumotex Sunny (left), merely need seats unclipped before a freshwater hosing and a wipe down. A river paddle on a warm day won’t even require a rinse: just wipe the boat dry and roll up till next time.

Tested: Kokopelli Moki II inflatable kayak review

See also : Moki II preview

In a line
Good-looking, roomy, high-pressure package that’s as wide as a packraft and turns like a tanker.

Good colours and design, as IKs go
You get everything in the bag except a paddle
Removable DS floor for easy rinsing and cleaning
Adjustable footrest tubes and useful velcro tube-top paddle holders
Massive 12-inch tubes mean payload is probably as big as claimed
Slow to turn and unresponsive to steer
Nearly a metre wide
Thin, hard seat bases
Too bulky and heavy for easy travelling
Massive 12-inch tubes mean not that much room inside at either end
Error-laden Kokopelli online specs [at time of review]

What They Say
The innovative Moki II two-person inflatable kayak offers an option removable spraydeck and sprayskirt. Giving you even more paddling options, seamlessly convert from a one-person to a two-person boat by simply adjusting the seats. Weighing 53lbs, the Moki II features a 2 person spraydeck removable spraydeck and 2 Alpine Lake Sprayskirts, high pressure rigid drop-stitch floor, user friendly push-push valves, 9” removable tracking fin and packs down seamlessly to fit into the included full-size premium carry bag. It’s ideal for flat open waters, touring, and ocean paddling. 

Out of the bag

Your ‘premium carry bag’ is a giant roller suitcase with a rather optimistic backpack harness and, on this unused boat, the pulling handle was already coming away. The bag weighs 27 kilos with everything in it and once you start unpacking, stuff just keeps coming out: hull, floor, pump, footrest, tandem deck, spray skirts and coaming rods, a skeg and a repair kit.

Weight: 24kg (53lbs) • Full kit in bag 27kg (59.5lbs); boat with seats 21.5kg (47.4lbs)
Length: 4.3m (14 feet)
Width: 91cm (36″) • undecked 99cm (39″); with deck 96.5cm (38″)
Sidetube ø: 21.8cm (8.6″) • 30.5cm (12″)
Payload: 272kg (600lbs)
Pressures: Sides 0.17bar (2.5psi); DS floor 0.27bar; (4 psi) • Set-up leaflet says: sides 0.27bar (3-4psi), floor 0.69bar (8-10psi)
Construction: 840D nylon inner/top; PVC tube undersides and floor skin; PVC bladders; 1000D removable PVC DS floor.
Price: U$ 999; UK £950

Based purely on online photos and specs, my Moki II preview a of months ago brought up anomalies with the boat width. Getting an actual boat allowed some of these specs to be verified in red, above. Some are out by 50% and the claimed packed size of 29″ x 14″ x 13″ is more like twice as wide. You can tell from the rambling, repetitive ‘What they Say…’ quoted from the same page above that it was hastily put together. That’s a shame as from first appearances, this cannot be said of the boat itself. And from the exceedingly low psi figures quoted, it’s not like it’s the usual ‘tactical exaggeration’ to make the Moki II look better than it is. You’d hope someone at Kokopelli might find ten minutes to correct the online specs.

Enough moaning: time to man the pump and straight away I really liked the compact black Nano barrel pump. The feet clip down, T-handle extensions screw on, there’s a lever to switch from two-way pumping (up and down) to down-stroke-only (less effort), plus a pressure gauge on top and a not-really-needed suction port for full deflating. It’s one of the best compact IK pumps I’ve seen. Kokopelli don’t list it but if you can find it online (the Aqua Marina looks similar), get one.
I was easily able to inflate the DS floor to 8-10psi on the two-way setting but later, topping up on the water with the pump on the boat’s DS floor, found one-way easier to do one-handed. Being a small volume pump of about a litre, the 12-inch side tubes took at least 100 strokes to reach 3-4psi. The inflated boat now looks pretty massive so the 270-kilo payload rating does not look like a mistake or exaggeration.

It was here I realised I should have RTFM, but then again I like to follow my intuition and see if it works. I had to re-deflate the sides to allow the pumped-up floor to centre correctly. Unlike with Full DS IKs, the Moki’s round side tubes hold the floor firmly in place without the need for any clamps or tabs.

The top/inner parts of the hull (mostly yellow, grey at the back) are woven 840-D nylon, possibly backed with a PU coating for waterproofness, and certainly with a water repelling DWR coating on the outside. This stops the fabric ‘wetting-out’, although from jackets and tents I know DWR needs reproofing and curing with an iron once in a while. Without it, the nylon will soak up water and take forever to dry. Full PVC (or rubber) tubes are better in this respect but nylon makes it easy/cheap to sew on fittings like the velcro paddle-holders, footrest daisy chains, carry handles and D-rings for the seat backs, plus short access zips at each end to get to the PVC bladders, if needed.

They yellow sides are stitched to the grey PVC underside of the tubes and the PVC floor sheet is heat welded to the tubes: all very neatly done. This is the nifty thing with PVC: surgically clean heat welds rather than the laborious, messy and vapourous glue needed by rubber-based IKs.

Apart from the crinkles at the bow and stern (which have thin plastic shells inside to help tidy the form), it’s all a very neat job. On the underside is the slot-in mount for the tracking fin (skeg), a stern drain plug accessible via a zip from the inside, and up front a shallow keel strip: more about that later.

Next are seats and footrests – no loose item here escapes ‘Kokopelli’ branding. The firm EVA foam seats are common on many IKs these days, but stiffness is best suited to a backrest, not a 4cm-thick seat base which, sat on a firm DS floor, may be too low for a an efficient paddling stance and too thin for all-day comfort. It’s something easily fixed with an inflatable cushion like a packraft seat base. More seat ideas here. The generous width of the Moki II means raising the seat is unlikely to affect stability.
The seat bases adhere to velcro strips sewn then welded to the DS floor. It’s an easy way of doing it while the velcro lasts. I found when sat in the front I was right at the end of the velcro; another foot would be handy, then you could fit a third kiddy seat in there.
A non weight-bearing backrest is a better use of stiff foam. They’re tensioned from the front and rear to stay upright; a floppy seat base is very annoying when getting in is awkward. Wide adjustment helps you fine tune them and on the back you get a handy zipped pocket and bottle holder.

The footrests are thick foam tubes commonly found on cheaper Sevys the like, and are threaded with a strap which clips to daisy chain loops stitched to the hull sides. Unused loops could also be used for securing gear because mounting anything under the bungie laces at either end of the boat is not such a good idea for forward visibility, accessibility, security, dryness and windage. These bungies are more useful as a quick way to stash a paddle.

Set up like this, the boat is a brawny 39 inches wide (99cm) but adding the zip-on deck and coaming rods pulls the boat in to 38 inches. Including a deck is a nice touch, so is the option to use it. On IKs I find them rather less useful than they seem: they make access, loading and getting in and out more awkward and if you’re worried about getting wet, paddling may not be for you. Once you pull on the also-included spray skirts you will be snugly encased in your Moki and ready to hit the rapids or surf. I’d have sooner had these items offered as optional extras, as most others do, and seen a cheaper boat.

On the Water

Initially the Moki 2 looked huge, but it’s actually a foot shorter than our old Seawave and so didn’t look too out of place on the car roof. We set off in search of a accessible fresh water and after a while found a trio of co-joined lochs off the B8073 feeding the steam which soon drops into Tobermory.

Topping up the Moki II on the water (all inflatables benefit from a top-up once put into cold water), the barrel pump stood on the firm floor and with one handed, one-way down-pumping, it was easy to attain the 4/10psi (0.27/0.69 bar) maximum pressures. This is Scotland in late August so there was no risk of the blazing sun bursting out ripping the boat asunder.

I set off without the tracking in and, as expected, found my front load on the keel strip make for tricky tracking. The deck was easy to manage but to me is a nuisance. It zipped off in seconds and got left on the bank.

It may be a metre-wide bladder boat but it’s still a kayak and so feels great once gliding out over the water with a splish-splosh, splish-splosh. The Moki II needs a bit more propulsion to what I’m used to, but the mattress-like stability will be reassuring to beginners.

It was only flat water so the apparent stiffness from the DS floor and high-psi side tubes didn’t feel any greater than my 2.5/4psi Seawave. Unless you’re braced properly to the boat (the problem with just about all IKs) there is little actual benefit to be had in paddling efficiency, just the longer glide. In rougher water you imagine it might come down with a slap as it drops into wave troughs. According to the GPS the two of us could sustain about 5-6kph which is pretty good, but an all-out burst only recorded 8.4kph (5.2mph) when I’ve got 10kph alone in similarly long but less-wide IKs.

It soon became apparent that the Moki II tracks rather too well; something I’ve heard of other DS IKs with frontal keels or fins. Turning it even a few degrees was a huge effort. In the end we had to resort to digging the paddles in and drawing them forward to force the boat round. The problem with this technique is it kills momentum, though it’s possible you’d get used to working the boat in a less drastic manner.

You also notice that two-up there’s not much room for gear because the side tubes are so fat. The last foot or two at each end can’t be used much – again a common story with big-tubed IKs, if not any pointy ended kayak.

We scooted through the reeds which whined like sirens against the PVC hull, then passed under a rickety wooden bridge to the middle loch. This led to another reedy strait into the last loch above Tobermory and a view towards what was probably the 528-m flat cone of Ben Hiant over on Ardnamurchan. The sun came out, the sun went in and eventually the little camera’s batteries died after too much videoing.

Next evening promised to be sunny too, but it wasn’t. I wanted to explore more the slim sea loch at Dervaig and had timed our put-in at least an hour after low tide so if the narrows leading out to sea turned into the Falls of Lora we’d get swept back in, not out into the Minch. The 10-minute portage over the tidal slime raised some grumbles from the crew not used to lugging 25-odd kilos of packboat across the mire.

I managed to wade through some shoe-sucking, shin-deep sludge to reach enough water to float on without the 9-inch fin, then paddled over to somewhere deeper where the crew could hop in and the fin get fitted. First thing I’d do with this boat is cut that fin down. Another issue I noted is that the woven yellow hull fabric may shed water readily, but picks up any smeared muck rather well. More cleaning before returning to the rental place tomorrow.
We headed out towards the narrows in the grim, grey light, feeling altogether uninspired.

‘The tide is going out, we’re all going to drown!’

‘It’s just the breeze over the surface. There are no times for Dervaig but Calgary to the south and Tobermory to the north were at low water nearly 2 hours ago.’


‘I’m telling you, the tide is going out!’

As we neared the malignant, 80-metre wide cleft on Loch An Chumhainn, ominous whorls bubbled up from the silty abyss and on entering the chasm the flow was clearly on the ebb.

‘I told you it was going out. Idiot!’

‘You watch, any minute now it’ll miraculously reverse, like it did on the Adur last week.’

I know tide times are only predictions but this was indeed odd and yes, I checked against BST/GMT and checked again I’d not misread 16.46 as 6.46pm. The tide should have been coming in for 90 minutes. I’d expect a constricted sea loch like this one to be a slow to fill and fast to drain, like Chichester Harbour in Hampshire. But that is a massive pool, Loch Chum is tiny.

We were now being swept down the Narrows of Chum at a slow walking pace and it was time to make a decision. Carrying on would take us two clicks to a jetty at Criog which we’d recce’d that morning on the bikes. That would be a long walk back to the car, so we dug in for a handbrake turn and escaped from the imminent maelstrom at a reassuring clip.
I recently read a review of a Sea Eagle with a frontal keel lobe which the owner said made the boat very hard to control against a current (as you’d expect). With the Moki II we had no such issues. There is not so much to explore in the inner bay but the tide would now be even lower with even more seaweed-draped, ankle-twisting shite to traipse over before getting onto to the ankle-twisting, midge-infested peat bogs above.
Wading in after the fin started grounding, in the end we found an easier take-out, followed by a 10-minute portage back to the car. I need to ask a Dervagian about these tides.

That evening I rinsed and washed the boat, but with little chance of it drying off any day soon. The removable floor made the task easier and the muddy smudges on the yellow fabric lightened up with a bit of brushing. I couldn’t be bothered to check if the inner bladders were dry as there was little I could so about it.

Summary
The Moki II isn’t an IK I’d choose to own: too wide, too bulky and heavy, probably too slow solo, too bladdered and too pricey with the unneeded accessories. But it’s roomy, stiff, yellow and like any IK, is fun to paddle.

Some similar DS-floored IKs

Measurements unverifiedWeightLengthWidth
Aquaglide Chelan 140 HB38lb / 17.2kg13′ 9″ / 4.2m34″ / 86.3cm
Decathlon Itiwit X100 3-seater39.7lb / 18kg13′ 5″ / 4.1m40″ / 102cm
NRS Star Paragon Tandem59.5lb / 27kg15′ /4.6m35.5″ / 90cm
Gumotex Thaya39lb / 17.7kg13′ 5″ / 4.1m35″ / 89cm
Sea Eagle Explorer 420X48lb / 22kg14′ / 4.3m39.5″ / 1m
Advanced Elements StraitEdge2 Pro41lb / 18.6kg13′ / 3.9m35″ / 89cm
Aqua Marina Steam 41235lb / 16kg13′ 5″ / 4.1m31.5″ / 80cm

Paddling with a Yakkair Full HP2 dropstitch IK

See also:
Full DS Buying Guide

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French paddleboat, board and ball-point dinghy manufacturer BIC Sport joined the full dropstitch (FDS) market a couple of years back with three models of Yakkair Full HP: the 1, 2 and le trois. Made in Vietnam, the 2 goes for at least £1200 in the UK.

Yak owner Robbo uses an ultralight ripstop, rip-cord
paragliding backpack-bag for his Bic.

The ‘Full’ is an important addition to the name which gets emblazoned on the hull, because the previous Yakkair models (above right) were just called HP 1, 2 and maybe 3. They had a DS floor between regular round side tubes.
The old models didn’t really jump out off my IK radar; they looked too much like some Advanced Elements IKs. But looking at the inset diagram above, it looks like they tried to address the flat-floor with a keel tube tucked underneath the outer shell.

On the water under the weight of a paddler it supposedly deformed to produce a double concave profile – a bit like the Kxone/DS Kajak AirTrek floors – and which looks like it will work better than a totally flat floor. Even with a skeg at the back, this barge-like flat floor common to DS IKs does make me wonder how they’d handle or track.
Bic owner Robbo has a variety of slip-on skegs and for this run he selected a medium in orange.

You get two clip-in SoT contoured-foam seats which have a well-braced backrest but, with bases an inch or two thick, won’t raise the butt above the ankles to give an efficient paddling posture, IMHO. Many IKs are like this out of the box, but raising or replacing the seat base is dead easy. I put my shoes under my Sunny seat: much better, but really you can’t beat an inflatable seat base like a packraft seat.

For solo use it looks possible to position the front seat back to the next D-rings, except there’s nowhere to clip the foot brace, which on the Yakkair are just a couple of padded straps. You could maybe use the front seat mounts. A good way to make a firmer and more effective foot brace is to slip a bit of 4-inch ø plastic drainpipe over the strap (right).

At each end you have two chunky carry handles as well as those fairly useless elasto-nets so common to many IKs. What would you put there that wouldn’t be more secure and more accessible lashed down by your feet or behind you? Not needed today, but the Yakkety Yak has a dinky slip-in spray visor up front to keep the splash out.

Talking of splash, I was keen to see the notorious side-floor join I wrote about. Sure enough, the Yakk’s floor is glued to the hull casing floor beneath and taped the side panels. But not all the way and so water and crud will run into the cavities at each end (below left) and then run down behind the tape along the sides. You could get rid of most of it by standing the boat on its end and opening the drain at the stern. And if you think there’s a lot of grit and other debris in there, hose from the top and let it run down the inside edges and out the drain. As for drying: that will take as long as it takes.

Sat inside, the boat is over half a metre wide because so much space is saved by the flat DS panels. But measured at 87cm wide (33.5″), the FHP 2 looks a bit on the wide side. Many FDS IKs look the same but have various widths: the HP2 seems about average. The much cheaper Decathlon Itiwit X500 is an unnerving 64cm, but even it seemed pretty wide when I looked at one in the shop. My Sunny was some 20cm less wide – and that’s with round tubes!

yakfhp2-4way

Flipped over, the bow looks a lot better formed than a typical full-tube IK, perhaps to compensate for the flatter floor. It’s actually a solid plastic moulding so should be immune to wear as the boat comes in to shore. But coming back down the Adur into the wind and against the flow, E & L had some trouble tracking straight. The two of them combined probably weighed less than me and with the featherlight L in front, the lifted bow was not cutting down through the water – the trim was out. Swapping seats with the heavier E up front would have fixed that, but it was thought the more powerful paddler should be at the back. Kayaking lore seems to agree, though two-up in my IKs (same-ish length) my generous mass is better distributed up front. To me it’s obvious: better to have the larger mass (my torso) towards the centre of the boat, not the stern.

Watching the Yakk navigate 20-km of flatwater for a few hours didn’t me inspire to even ask for a go, far less to own one. Used to being snuggly jammed into IKs & Ps, the canoe-like width and low seats put me off and set-up was without footrests would have made it too much like sitting on a log. L & E were first-timers in this boat afaik and initially found it tippy though soon got accustomed (they looked pretty relaxed).

The quality of assembly certainly corresponded with a four-figure IK and it sure looks less bloaty than a Decathlon Itiwit we met – the IK sales hit of 2020. I suspect this image is the attraction to many FDS buyers, but for me the water and grit-trapping cavities would add extra maintenance, even if it wouldn’t be that hard to fabricate and glue in a PVC cone to seal them off for good. Then you could simply rinse, drain, deflate, wipe off and dry the Yakkair like a regular tubeless IK. And the other drawbacks: seats; footrests; thigh straps are easily added. The you’d have a stiff and spacious tourer with great paddler ergos.

New Yakkair HP1 owner, Kevin A, adds:
Having just bought a Bic Yakkair Full HP1 to replace an ageing Walker Bay Airis which has become porous after about ten years of excellent service, I was very interested to read this review and I thought I would add some early impressions of my own boat.  So far, I have only had it on the water once because I have ordered a new combo paddle which can be a kayak paddle, a canoe paddle or a SUP paddle – I generally prefer using a single canoe paddle but the one which I have been using for years is a bit too short for the wider new boat.  You mention the width of the HP1 in your review and you say that you prefer a narrower boat but, for me, the extra width was part of the attraction.  I’m not sure yet about how it affects the stability and handling but, tbh, I just prefer the appearance of the wider boat even though, as you suggest, it does make a footrest essential so that you can brace yourself better – in my other boat, I was held fairly firmly at the thighs by the narrow interior.  The footrest which came with my boat seems to be a bit more substantial than the one you describe in your review.
Looking around at the various marketing pictures, I think some of the details of the package are a bit variable and maybe the footrest falls into that category.  But the biggest difference I have spotted is the style of the carry bag for the boat and I have to say that the carry bag which I have been supplied with is fantastic.  It is superbly well made and looks like a fairly upmarket piece of luggage – on the occasions when I take the boat on public transport I will no longer feel quite so conspicuous (the downside – there’s always a downside! – is that the bag itself adds weight to the whole package).  The real surprise about the carry bag is that it swallows up the entire rig – hull, paddle, pump and seat and there is still room for all the normal bits and pieces of personal kit.  The downside of that, of course, is that it is very big and only just about manageable by a single person – there is definitely no chance that it will ever be carried on my back using the excellent quality backpack straps which are part of the bag’s construction (I’m seriously tempted to cut the straps off).
The only area which I still have to work out is, as you say, how to deal with getting the water out of the joints between the three panels.  I’m not sure that the material itself will absorb much moisture and I’m hoping that removing the end plug and propping the boat up on end for a decent length of time (half an hour?) will allow the joints to drain pretty thoroughly – if necessary, I will have to re-inflate the boat at some point in order to ensure that it is completely dry.  By the way, I think that the so-called self-bailing drains are only really intended for use in seriously white water when the boat is in danger of filling up completely – in those conditions, it would be quite normal for the boat to have quite a lot of water sloshing around but the self-bailers would help to keep the level down (I only ever paddle on flat water so I have no idea how effective the self-bailers are in practice).
Happy paddling!

Advanced Elements AirVolution Dropstitch Kayak

See also:
Full dropstitch kayaks
• Decathlon X500
• Gumotex Thaya
• Gumotex Rush

US IK and iSUp brand Advance Elements have come up with a sleek and innovative new angle on full dropstitch kayaks (F DS IK): The AirVolutions feature a high-pressure twin-panel/chamber ‘clamshell’ design where the upper DS panel is a demi-deck. With minimal stowage below the decks, it resembles a Sit-On-Top, except – though not currently offered – should you wish you could fit a spray skirt round that coaming (cockpit rim) to be sealed right off.

Airvolutions do not have a ton of storage space below deck [and] are designed to be Recreational/Day Touring kayaks

There are Solo and Double/Solo models with dimensions below. The more I study Full DS IKs, the more I think what you gain in rigidity you sure pay for in weight over similar non-F DS IKs, some with just a DS floor. Maybe dropstitch PVC tough enough to handle the intended use and pressures is simply a heavy, bulky fabric. In its wheeled duffle the folded up AirVolution2 is a massive 4 feet high and 18″ wide. As with many US-branded IKs, the Airvolutions are on the wide side, but it’s claimed they can be stand-up paddled if you have very good balance. That’s me out, then!

LengthWidthWeightPayload
Solo13′ / 3.9m33″ / 84cm39lbs / 17.7kg300lbs / 136kg
Double14.5′ / 4.5m37″ / 94cm52lbs / 23.5kg550lbs / 249kg

Both models are rated at a high-for-DS IK 10-12 psi / 0.9 bar (though they will work with less) and have another DS IK innovation: Pressure Relief Valves (PRVs) on both panels set to purge at a lofty, iSUp-like 18psi. Why not 12psi so you can blithely inflate away till the PRVs hiss? Some pressure might be purged over a hot day from the top deck but not enough to matter.

A few iSUps have PRVS, but I’ve not seen them on F DS IKs before and many potential owners will be reassured, as it should aid the as-yet untested longevity of DS panels. PRVs limit potentially destructive over-pressurisation when inflatable boats are left in the sun. Unlike flat DS panels, traditional non-DS round tubes spread loads equally (eventually seams will fail). Left in the hot sun while you’re having a siesta, the space yarn stitching (right) in the DS panels could be ripped apart which adds up to an irreparably ruined boat.

AirKayaks™ IK in the US seem to be a favoured AE outlet right now and have done detailed reviews of both boats with loads of photos and measurements, followed by a quick flatwater spin.
There you can read the double’s open hatch is nearly 4 feet (114cm) long) and, oddly, there are no footrests. Even taller paddlers won’t be be able to brace off the front cockpit rim unless the seat is too far forward. A stuffed bag would work, or it would be easy to glue on some D-rings to run a footrest strap and hard tube. On a raft-wide IK like the AirVo2, it may not be worth bothering with thigh straps. Both models run a huge 9-inch skeg which will ground easily in shallows and suggests tracking with the flat floor may need help. It’s easily be replaced with a cut-down spare.

Prices in the US are a typically reasonable $1100/$1300; in the UK the boat is mentioned but not available and it won’t be such a good deal. It would be a struggle carrying a 23-kilo boat too far so for your money you get a wheelie duffle but with tiny, pavement-only wheels and clearance. There’s also a repair kit and a high-pressure, two-way switchable barrel pump which may need some brawn to reach the full 10+psi. Because high-pressure IK pumps need to be tall and slim, they’re low volume so take a while. AirKayaks reported it needed 100-150 strokes to inflate each chamber. That is a whole lot of pumping for a DS boat, but electric car plug-in pumps are available.

The AirVolution2 looks like a great day kayak for two, but from the photo above, even tall solo users may be better off with the less huge AirVolution, unless you add a foot brace tube. With this design, either boat has less low-down storage space than a conventional fat sidetube IK like a Seawave. Storing gear under the deck bungies just adds windage and hampers steering and stability. For touring, what gear is less than 4-5 inches high could squeeze under the covered ends, and when used solo the double has about half a metre of room behind the seat and some in front.

It’s hard to be sure but inside it does look like the two panels have been ‘wallpapered over’ leaving no crevices to trap water and much more potentially damaging grit. This is a big improvement over hitherto conventional boxy three-panelFull DS IKs where water and crud gets in all sorts of hard-to-clean places. Being smooth inside, you’d think the AirVolutions could easily be drained by tipping upside down, then wiped down to dry. Maybe, but they’ve added a big plugged drain in the middle of the floor (left) to make that easier (it won’t work for self-bailing unless you’re very light). Judged against some of AE’s other ‘busy’ graphics, the blue boats don’t look too bad,

Up to now AE came up with far less elegant solutions to the problem of rigidity in long IKs. The AirVolutions: a pair of iSUp boards wrapped up and glued in the blue skin, are an interesting idea with some compromises, mostly in storage. These are day boats, not tourers, but there are many, many more day-paddlers out there.



Preview: Kokopelli Moki 2 IK

See also: Kokopelli Moki 2 tested in Scotland

Kokopelli are a US packraft brand who started out in a Denver garage in 2012 but soon moved on to full Asian production. Known for their distinctive range of yellow TPU or PVC packrafts – long, short, bailing or decked, with the Moki I and Moki II they’ve moved into IKs.
Both Mokis are what they’re calling hybrids: dropstitch floors with conventional side tubes. Warranty is a generous 3 years. As always here at IK&P, it’s the the two-seater’s added versatility as solo tourer that’s of interest. The online stats for the Moki II are:

Weight: 24kg (53lbs) • Full kit in bag 27kg (59.5lbs) ; boat with seats 21.5kg (47.4lbs)
Length: 4.3m (14 feet)
Width: 91cm (36″) • With deck (39″); no deck (38″)
Sidetube ø: 21.8cm (8.6″) • 30.5cm (12″)
Payload: 272kg (600lbs)
Pressure: Sides 0.17bar (2.5psi) ; 0.27bar; DS floor (4 psi) • Set-up leaflet says: sides 3-4psi, floor 8-10psi
Construction: 840D Nylon side sleeves for PVC bladders; 1000D PVC DS floor
Price: U$ 999 (with tandem spraydeck); UK £950

Renting a Moki 2 a couple of months after this was written revealed several errors in the online specs which could easily be verified or cross-checked. Only the length was spot on. The set up leaflet also refers to ‘… the packraft’ a couple of times, as if it was hastily copied.
Verified figures are in red above.

Big, 21.8cm nylon sidetubes house PVC bladders which take an above-average 2.5 psi (0.17 bar) while even the dropstitch floor (DS-F) only runs an oddly low 4.5psi. That’s about the same as my uprated Seawave or a similar, regular-tubed Grabner. Can a DS-F IK be too stiff? Possibly. Turns out official online data is wrong.
As with many bladder boats and/or part or full DS IKs, weights tend to be higher and the Moki is more than most, but this may include all the extras, not least a huge roller duffle with backpack straps. The 24kg weight give may well add up to the boat with the deck and skirts.

According to Kokopelli, the Moki II is rated as ‘Lake’ but it’s also rated for ‘Fishing • Oceans • Travel’.

The well-featured EVA foam seats look a bit thin in the floor, but that’s easily altered and they can be positioned securely anywhere along twin velcro bands on the floor, with the backrests braced off the hull top in both directions. A lot of IKs have these bow and stern bungies which are handy to slip a paddle in while you fiddle with a camera, but you’d not want to use them for anything important or bulky. Not listed, but you can also use velcro tabs on the side tube tops to secure paddles. The specs claim there are a dozen D-rings but they are just the bungies being repeated. There are no D-rings in the boat.
The foam rubber tube footrest/s can be repositioned in daisy chain loops, presumably sewn to the DS-F casing and there a huge, clip-on skeg (tracking fin) plus what looks like a shallow front keel to help the flat floor track straight.

The zip-on tandem zip-on deck with coaming rods and skirts come with the boat too (hatch length: 86cm, 34″); an optional solo deck is available. Plus you get a compact, two-way barrel pump and a repair kit. Add a paddle and some water and you’re all set.

At the listed three feet or 91.4cm, both Mokis are pretty wide as so many US-branded IKs are (one reviewer verified a Moki I at 37″ wide). See true figures above. But something looks wrong with the stated dimensions (left). If the internal width between the tubes is 14″ and the side tubes are 8.6″ each, the total is 32.2″, nearly 5″ narrower and about the same as my old Seawave. That’s more than wide enough to be stable but nippy. I asked Kokopelli; someone replied but never got back and the website remains unchanged. From the proportions of the images above, the actual length looks somewhere between the two. Discrepancies explained by verified measurements, above.

We paddled a Moki II for a couple of days. Review coming soon.

Kokopelli’s page

Preview: Gumotex Rush 1 and 2 IKs

Gumotex Rush (D-SF)

Interesting discussion
Another detailed online review
All Rushs out of stock till March 2021
See also: Zelgear Spark 450
A D-S floor Seawave is due end of 2021

Gumotex are moving on up with hybrid drop-stitch technology, originally showcased in 2019’s Thaya which is basically an old Solar 3 with a D-S floor to make it more stiff. The new-for-2020 Rush 1 and 2 (left) is the ‘Swing Evo’ mentioned in that Thaya article.

The new Rush models came out in April 2020, just as the pandemic hit and lockdowns/shutdowns spread across the world. It’s also said there was some kind of quality control calamity at the Gumotex factory which led to many completed boats getting shredded. As a result, stock of Gumotex IKs dried up over the summer when post-lockdown IK demand went ballistic. Other IKs came back online but the Rush was put to the back of the queue. At the end of 2020 all boats got the rumoured price hike, with the R2 going up to €1500, even though they will not be available till March 2021.

‘Hybrid’ is a cool word for a kayak which isn’t a Full D-S like a Sea Eagle Razorlite and many others. They’re assembled from three flat drop-stitch panels making boxy hulls (right) which, according to the graphics on this page, may be sub-optimal in choppy waters. Me, I think a full-width flat floor is as much to blame, but the Rushs get round this with raised side tubes.

Derived from iSuP boards, D-S has become a blessing to IK floor design which hitherto had to use I-beams of parallel tubes (left) which complicates assembly and is prone to ruinous rupture if over-pressured, unless fitted with a PRV or the IK is exceptionally well made.

A Gumotex hybrid IK (below) retains the regular round side tubes of a classic IK for better secondary stability (afaiu) but features a D-S floor for much-needed rigidity. However, unique to Gumo, D-S end-panels are also used on the bow as well as shorter and less obvious panels at the stern.


A word about this fabric paraphrased from here:
Nitrilon-Dropstich is composed of a core of 1100 dtx polyester fabric made up of two sheets joined by a mass of threads exactly 10 cm long. Unlike regular PVC-based iSuPs and D-S kayaks, the durable elastomer plastic coating is not glued to the fabric, but ‘pressure-impregnated’ which eliminates delamination risks more common with bonded PVC coatings. An additional layer of polyester-reinforced Nitrilon is vulcanised to the floor bottoms making them double thickness.”

The Rushs differ from the Thaya (1st gen Gumo D-S) with the panels forming a more ‘hydroformed’ bow, another weak point with regular blunt-nosed tubed IKs. The Rush’s bow makes a water-slicing wedge sharp enough to cut ripe avocados.
The semi D-S side tubes are more complex than a D-S floor attached to two round side tubes (like the Thaya and some AquaGlide IKs, for example) and explains the high price.

The vital stats on the tandem Rush 2 are said to be 4.2m long x 82cm wide. Compare that to my Seawave at 4.5 x 78; the Seawave has an 11% better length/width factor (LWF) of 5.77 vs 5.12 over the Rush 2, but those are my Seawave measurements. The side tubes are said to be 19/20cm on the Rush compared to 22 on my Seawave. This and the length may contribute to the load rating dropping to 195kg vs 250 on the longer Seawave. That’s still plenty, unless you’re hauling a moose carcass out of the Yukon.
The official weight varies between 15.5 and 17kg, depending on where you look online. The higher figure is the same as my modified Seawave with packraft seat mod.

Pressures are another obvious difference with the Seawave. The 6cm D-S floor runs at 0.5bar (7.2psi), actually a modest level for D-S, but an IK doesn’t need to be as stiff as a iSuP board.
The slimmer side tubes now 0.25 bar or 3.75psi (same as the Seawave). Well, that’s according to the table from the online manual shown below. Many outlets still list 0.2 sides and so did the Gumotex website until mentioned it to them.

0.25 is a bit higher than normal IK pressure but not quite as high as 0.3 in a Grabner, a Zelgear Spark or the 0.33 bar on my modified Seawave. When you combine that with the stiff D-S floor, the 0.25 sides must make the Rush IKs Gumo’s stiffest IKs by far. The difference is, I added PRVs to my Seawave sides before running them at 50% higher pressure to automatically protect them. The Rushs don’t have any PRVs which explains the warning in the manual, above right. It’s odd but worth remembering that my super-stiff Grabner Amigo didn’t feature any PRVs either, not even in the floor. Quality of construction (gluing assembly) must have a lot to do with it.

When you add any colour you want as long as it’s black, you do wonder if no PRVs is a good idea, because in the sun black things get hotter, faster. Black may be great for Cockleshell saboteurs, not so good for visibility at sea and it kills photos stone dead.
It’s true the Innova-branded Swings in North America have long had black hulls and no one complained. But they run 0.2 bar so need help in stiffening up in the hot sun. They also have fixed decks in red. Many Grabner IKs are now made with black exteriors too (right).
One assumes the Rush’s grey, lowish-psi D-S floor can handle increased pressures from passive solar heating, especially as it’s in the water most of the time. But the black side tubes will get taught which becomes a nuisance to manage (or worry about), even if tubes/cylinders handle high pressures better than flat slabs.
In fact, as you’ll see from the comments below and elsewhere, Gumotex have found black is not notably worse than red or green in absorbing solar heating and dangerously over-pressurising. And if you’re that worried it would be just as easy to install PRVs in the Rush side tubes, as it was on my Seawave.

Because a D-S floor is flat, one imagines it will hinder effective tracking, despite having a skeg at the back. The flat hull will plane over the water and wander off to the sides like a packraft – the so-called ‘[windscreen] wiper-effect’.

So, similar to Sea Eagle‘s patented NeedleKnife Keel™ (right), Gumo added a more discrete ‘keel hump‘ under the bow (left) to compensate for the lack of old-style parallel I-beam floor tubes which added a directional element. You can see from the overhead image above that this keel hump is mirrored on the floor inside the boat, either by design or need. This protuberance makes a high-wear point on the IK in the shallows so it’s just as well the floor is double thickness Nitrilon, as mentioned above. It’s the same on any boat. On my Seawave I pre-emptively added a protective strake – a strip of hypalon – to the central tubed rib, though to be honest it never got much wear as i try and be careful. Mine was hardly worn in five years of mostly sea paddling.

Rushs can be fitted with optional decks (green on the R1, above, red on the R2, below), using the same velcro system as the Seawave, with those horribly bulky alloy spars (right) supporting the decking (surely a flexible rod like tentpole material wouldn’t be hard to make). I read on other reviews that they’ve greatly improved the coaming (hatch rim) so that spray skirts attach more securely.
The footrest appears to be the usual rubbish cushion adjusted by strap and seats can be moved to a variety of positions, too.
Seats are now solid foam, but the base looks too thin and low to me. A stiff foam backrest (with side bracing straps) is good, but an inflatable seat base is much more comfortable to sit on because you can vary the pressure and so the height. Unlike anything inflatable, foam eventually loses its cushioning. But an inflatable seat just doesn’t need to be made of hefty hull-grade hypalon, as on other Gumo IKs (more in the vid below). But anyway, a seat is easily changed to suit your prefs. More on IK seats here.

Below, a review of a Rush by Austrian Steve. Can’t understand a word but some observations: I like his convertible Eckla Rolly trolley/cart/camp chair; also love the lovely long canoe chute at 20:40. Have to say though, I winced a bit at some boat dragging here and there. Do the right thing, Steve; it only weighs 12kg! Note also this shortish boat seemed to track pretty well without a skeg – the frontal keel-hump may be effective in leading it by the nose, after all. But in the comments Steve admits the stiff, flat floor slaps down hard on wave trains coming out of rapids and I suppose would be the same at sea. It’s a drawback of flat, raft-like D-S floors.
See this for an easily translatable written review also in German.

The price of an R1/R2 has already jumped from a hefty £900/£1200 to €1150/1500, plus decks going from £200/310/370 (tandem). There’s also a rudder kit (price unknown) which will be similar to the Seawave unit. IMO it’s not so useful, even on the longer R2. But like decks, some may like the option.

As you can tell, I was comparing the Rush 2 with my 5-year-old Seawave and wondered if it might be time (or an excuse) to change. An unprecedented five years of ownership proves there’s nothing wrong with my Seawave [I sold my Seawave in May then bought another in October].
What are the benefits of a Rush 2? Black is not such an attractive or useful colour for a boat, and neither is losing a foot in length or 50kg in payload over the Seawave – at least at sea. On a river the greater nippiness from less length will have benefits, but for that I have a packraft. As for greater rigidity, it looks pretty good in this clip but my adapted HP Seawave was very good compared to the lower-pressure Gumboats, and it seems the speed (see below) is no greater. Being a bit shorter, I wouldn’t expect it to be.
The word is a Seawave with a D-S floor will be out at the end of 2021 but that will begin to approach Grabner prices. Gumotex had a bad summer in 2020; either due to lockdown shutdowns followed by very high demands for IKs, or as I read elsewhere, a failure in the PES core during testing which saw them ditch hundreds of boats. Who knows, buy by the early autumn of 2020 supply was creeping back, except for the exotic new Rushs.

Good owner’s review (in French)