A few years back we purchased a 'Suspenz All-Terrain Super-Duty Airless Canoe and Kayak Cart'. Pretty much the most heavy-duty advertised carrier for totin' kayaks and canoes that we could find on the market. In our case canoes. Requisite rough terrain and long distance capable. It pretty much sat unused in the gear room since purchase. We recently got back around to its attention. First off performing an initial test rigging and pull around the back yard. The load was a 34" beam, 14ft length (polyethylene) boat, say a fully outfitted 60lb weight. We subsequently took the same rig out to the river side for further testing prior to practical use. The test site was our usual river put-in consisting of a (say) 200ft length approach along a graded and easily traversed side hill cut dirt road leading to a concrete plank boat launch. The final 60ft parallels the immediate left bank along the mouth of a small feeder creek before onto the launch. Situated within the flood zone, the launch site and last 60ft of approach is frequently submerged during high water river and creek levels and subsequently backwashed with river silt, sand and cobbles. The flood events are most prominent late fall, throughout winter and into early spring. Ensuing flood scar soft sands and scour holes are usually raked over or bridged with readily available large rocks and rip-rap boulders as needed. Typically a bit coarse repair. We made sure to pull the loaded cart over every bumpy rut and protruding large rock along that final rough approach.
The cart, sporting large airless tire wheels, rolled great over even the worst of the terrain. We weren't quite satisfied with the load handling. The padded, adjustable factory "bunker bars", which support the load, just needed a bit more width and length. At least for totin' a wide, shallow arch canoe hull. The build seemed more aptly suited for a v-shaped or keeled kayak hull, similar to an ocean kayak. The canoe kept wanting to list left or right along the roll axis no matter how tightly strapped, dropping short side in between the bunkers. In turn the weight shifted accordingly to the high side resulting in imbalance and overturning the whole shebang. This was pretty much unavoidable on the rugged, rocky ground.

We decided to replace the bunker bars. After removal, we fabricated four 3" angle brackets to which was bolted two 3ft length wood 1X4 slats as a deck. We had a few 1/2" thick unused closed cell foam floor mats lying about from which we cut-to-fit several strips for deck padding. Contact cement worked fine for their attachment. We considered aluminum angle as opposed to the wood slats, just for a bit more professional appearance. Stuck to our usual utilitarian ways, though. Just looking for performance. The slats can alternately be attached right-angle to the cart if more width is necessary. In that configuration the original bunker bars can be reattached at increased width. We don't see any need for that - and still a modular option. We're thinkin', too, that longer slats at a right-angle configuration may allow loading of two boats. Something to eventually test.
We loaded this old Dagger OC1 to test it out. The boat rested a heck of a lot better. Pulled fine.
That boat has held up pretty well for the mileage. Purchased new in 1990 (see below)
The (otherwise roadless) local river gorge is easily accessed for endless miles along its length by a bordering rail trail bicycle and hiking path. Easy totin' for the canoe cart. Hence the cart's destined purpose - rail trail river access. Subsequently, at whatever intended destination reached we figure to stash the cart for later retrieval by bicycle. So we further fabricated a simple bike hitch attachment. Still a work-in- progress in these images, but the idea presents itself. Four piece assembly. A cut section of 3/4" galvanized EMT conduit bent at a 45º angle to clear the rear bike wheel. A matching straight section was u-bolted to the cart frame...
We found matching 45º EMT conduit fittings on-line, available from these guys '
Maker Pipe', for joining the conduit sections. We drilled out the connection to accept 1/4" hitch pins to hold the alignment and as backup should the connection vibrate loose while bounding along the trail...
A seat post swivel hitch was fabricated from a 1/2" cable thimble. The thimble and joining end of the 45-bent conduit was drilled out for fastening with another 1/4" hitch pin. First the conduit end was pressed flat to fit the notch separating the thimble. The flat was done by just pressing the pipe in the jaws of a work bench vise. The pipe flattened easily with no heating and with no subsequent splitting or cracking. A 1/2 split rubber pipe coupling was used for height adjustment of the thimble hitch on the bike seat post...
That's it - just needs a few minor adjustments
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Pulled from the archives. A couple old scanned 35mm prints of fourteen-year-old strong-man Matt and his first ever whitewater trip in that OC1 - 1992
Did superb. Though, a bit hesitant "rail grabber" in this shot while following one of the few small drops we led 'em over.
Quickly got the hang of it... river...
... and creek...