Gear: Tender

Our Tender Requirements

When it comes to a Tender or Dinghy, everyone is looking for something specifically tailored to their individual needs... and we are no different. Here are our top 10 requirements when looking at a tender or dinghy, the 'car' for your boat.

Low Weight - On a cat, weight always matters. Due to this, we won't be going with a hydraulic platform (as much as we would like to) because most of them cannot lift our dinghy choices! Plus, if we choose a light enough dinghy, we can drag it on shore. 190 pounds or less is our goal.
Open Space - With S/V Lynx carrying a larger crew than a typical boat, we need a tender that can handle our crew.
Durability - The hull must withstand beaching and the tube material must resist UV light, so we prefer Hypalon.
Hull Shape - Deep V. If we want a smoother ride in rough waves we need a higher dead rise with a deep V hull.
Tube Diameter - The larger the diameter, the better for a drier ride. We don't like getting wet, either from our butts hanging over the edge of a pontoon and getting splashed or due to spray from wave impacts dousing our entire bodies on our way to shore for a nice dinner. We are looking for 18" tubes.
Length - This matters because we have to fit this between our cat hulls, and 13' 9" is about the maximum width without encroaching on the sugar scoops. Therefore, we need a dinghy length of 13' or less. Ideally, the length would be about 12'.
Load capacity - We are scuba divers, so we need a boat that will handle all our gear and multiple divers and still get on a plain, 1500 pounds of LCC is our target.
Double Floor- We like our feet and items to stay dry, so a double floor keeps more water in the boat away from where your feet are standing.
Double Storage Lockers in the bow: This is so that we can put one of our batteries in the large compartment, and our anchor and chain in the other smaller one.
Price - Money is not unlimited, so this is a serious factor we have to consider. Our budget is about $6,000

Hull Types

When it comes to hulls on a Tender or Dinghy, there are three options, Carbon Fiber, Fiberglass or Aluminum. Here are our thoughts on which is the best hull material for our needs. We have five areas of comparison:

WEIGHT - First off, many claim that aluminum RIBs are lighter than fiberglass... and we have found this to be generally true. However, carbon fiber is even lighter. Therefore, all the RIBS on our list of contenders have aluminum or carbon fiber hulls.
DURABILITY - Next up is durability. If you plan on running your tender up onto shores covered with rocks, then the aluminum hull is your best bet as it is more scratch resistant and will tend to dent rather than fracture. However, there have been issues of aluminum hull welds cracking over time with the flexing of the boat, where fiberglass is more forgiving in this area and carbon fiber even far stronger Also, even though aluminum hulls are tougher against scratches, if you do get a scratch in your fiberglass or carbon fiber boat, you can easily mix up some epoxy and do a repair. Fixing any serious issue with an aluminum hull is far more difficult.
CORROSION - This is more likely on an aluminum hull. You can have one powder coated or painted, but then you risk bubbling of the paint. Some owners have reported this issue while others have no problems at all. Many people suggest a bare aluminum hull as the best bet. However, as one RIB maker states on their website, "Aluminum requires very little maintenance other than keeping salt off to protect the hull from corrosion." I guess the issue here is that we are going to be in salt water... constantly. Fiberglass and carbon fiber would have less issues with corrosion.
SHAPE - Fiberglass and carbon fiber boats can have a more polished and contoured hulls since they can be made in any shape where Aluminum has some limitations and tend to stick to a somewhat flat sided shape, with small ridges (see pics, below - fiberglass left, aluminum right).
NOISE -Aluminum hulls are nosier, where fiberglass or carbon fiber are easier on the ears.

Fiberglass or Carbon

Aluminum

Our Conclusion on Hull Material

Though fiberglass hulls seem to have a lot going for them, in the end, we prefer the better durability of the aluminum hulls for beaching. Carbon fiber is a lot stronger than fiberglass, and more scratch resistant, so we did not rule out that option. Therefore, in the comparisons (below) all of the contenders have aluminum or carbon fiber hulls.

What we choose for a Tender

Inmar, Model 365R-AL

Next is the 12' inflatable from Inmar. She is a light weight boat at 185 pounds Hypalon even though she has twin decks and a deep V hull. This boat is listed as 6 passengers, which is less than we would like, but has a 1525 pound load carrying capacity, so we could squeeze in a couple more! Like our three top contenders, the 365R-AL has 18" tubes, so that's a big plus. The max hp for the outboard is 30 hp, so that works for our 25 hp outboard.

In features, the 365R-AL compares well against the ZAR Mini and North Atlantic and comes in at a good price of only $5,595, plus tax and transport equals $6364.86 total. Because the dealer is fairly local, there are no delivery costs to us. That makes the 365R-AL the best priced boat we are considering if you take shipping and tax into account.

Standard Features:
Non-skid aluminum hull with deep "V", bow locker (fuel tank space with straps), double wall floor, aluminum outboard mounting plate, self bailer, leafield valves, over inflation valve, molded handles, heavy duty full length rubstrake, (3) davit lifting points, bow tow rings, oar locks with oars, removable rowing seat, foot pump with gauge, repair kit.

Her only real negatives are that she is only 12' long, losing six inches to the Zar and N. Atlantic, and Inmar isn't a world wide boat distributor, like Highfield or ZAR, hence, the lower price. Still, there are advantages to the 12' length, as it will be an easier fit between our sugar scoops.

Point Comparison Chart

Here is a list of the tenders we considered. We assigned a point value to each feature based on their importance to us. This allows us to get a quick comparison of the tenders we are interested in possibly buying. Don't forget to scroll to the right to see more of the chart, including the final totals.

Search:

Tenders	Weight	Pts	People	Pts	Hull	Pts	Tubes	Pts	Length	Pts	LCC	Pts	Price	Pts	Lasts	Pts	Total
Zar Mini 13	201	16	7	5	Deep-V	7	18"	12	12'6"	7	1512	8	$10,600*	10	10 yrs	4	64
ALA380L	195	16	6	4	Deep-V	7	18"	12	12'8"	5	1550	8	$6,324*	16	10 yrs	4	69
HF_CL380	183	17	7	5	Modr._V	5	17"	8	12'6"	7	1404	7	$7,214	14	10 yrs	4	63
Inmar365R	185	17	6	4	Modr._V	7	18"	12	12'	6	1525	8	$6,365	16	10 yrs	4	74
OC400	147	21	6	4	Shal._V	3	Hard	12	12'10"	5	1327	5	$14,000	7	30yrs	21	66

Showing entries (filtered from total entries)
NOTE: Prices with an asterisk (*) already have shipping, tax, and any other fees to California added, all other prices will be higher than indicated once those are added.

Our Conclusion on Tenders

Our top desires are low weight, double floor, large tubes, and 12' length. The total price also figures in heavily as well. So, looking at those factors, the Zar Mini RIB 13 and the Inmar 356R-AL were our top contenders.

They are very similar in features, with the main differences being that the Zar is 6" wider, and 6" longer, while the Inmar is 16 pounds lighter and $4,300 less expensive! (That was a big one).

Therefor, the Inmar 365R-AL came in as our #1 boat, 5 points ahead of the North Atlantic, 8 points ahead of the OC, and 10 points ahead of the Zar.

We will pare a Zerojet 25 hp electric outboard and have a Spirit 1.0 Evo as a backup motor (see below). As for which outboard we will use on our tender, that's up next.

Though we like the North Atlantic, OC, and Zar boats, the Inmar won out on a combination of price, weight, and having all our desired features, so that is the boat we ordered.
Sea trials and videos to follow once we get our Zerojet Outboard in 2026.

Dinghy Motors

The first choices to make are a gas, electric, or jet.

There are advantages and disadvantages to these three options, as follows:

Advantages

Gas outboards - They have greater range on a single excursion since gas is more energy dense than batteries. They also weigh 113 pounds less than an electric motor and batteries. Most importantly, the initial cost is far less expensive to purchase than electric outboards and their batteries by around $15,000! (but that's not the end of the story, see disadvantages below)
Electric outboards - They require no gas stored on the tender or main boat and have endless numbers of excursions due to available solar recharging on the main boat. They make no fumes and are quieter. They start without a pull cord, and do so, every time. They require no warm up time before heading out They can be lighter on the stern of the tender (battery weight can be moved forward). There is less weight on the main boat since we don't have to store flammable gasoline. They cost more to buy, initially, but will save us around $16,000 in gas over the life of the batteries.
Electric Jet - We only have one option here, and it is a new one. The two big advantages are no propeller to break and nothing sticks down, making your boat shallower draft, with no need to raise (tilt) an engine.

Disadvantages

Gas outboards - They can have trouble starting. They require more maintenance, They have flammable fuel, which require trips to find gas to refill. Gas outboards have a limited number of excursions before running out of fuel. And, if you want to extend the number of excursions, they require extra, flammable, fuel to be stored on your main boat. Gas must also be purchased, and at $5 a gallon and the motor burning 2.3 gallons an hour, it costs $11.5 dollars an hour (though it travels 25% faster than the electric outboard). The electric motor battery lasts 3,500 charges. During that lifetime, that equates to the gas costing $30,000 more over the electric battery which costs about $14,000.
Electric outboards - With a 10kw battery, they weigh 303 pounds. That is 113 pounds heavier than the gas outboard option (motor and 10 gallons of gas). They are limited in range to 14NM on a single excursion if you desire to 'go fast' at 16 knots of speed. And, they have an initial high price! If you add two 5kw batteries, they are initially far more expensive than gas outboards by about $15,000 (but make up $30,000 in fuel savings over the life of the batteries, so the net savings over the gas option is about $15,000 in the long run).
Electric Jet - With the batteries, they are heavier than the gas option. They have limited range on a single excursion if you desire to 'go fast' . Unfortunately, they are far more expensive. With a Highfield Rib, the jet motor plus batteries runs about $35,000 vs $18,900 for the electric outboard and batteries (though for fair comparison add another $7,100 for the RIB for a total of $26,000), or just $11,000 for the gas outboard and RIB. Finally, the mounting is permanent, so we cannot remove the jet from the tender and use our waterproof Spirit 1.0 Evo and battery for beaching in surf and dragging our lighter dinghy up the beach.

Our choice between Gas, Electric Outboard, or Electric Jet

Originally, we decided to buy an electric outboard, but couldn't find one that was powerful enough at 48volts and was powered by LifePo4 battery chemistry.

But that has recently changed! Zerojet has come up with exactly what we are seeking, a 20kw (25 hp) electric outboard that runs on 48v LifePo4 batteries, and weighs only 83 pounds!

Perfect!

Therefore, we have chosen a the Zerojet 20kw electric outboard over the gas outboard or jet. It is lighter to remove the outboard easily when we want to change convert from a fast tender to a slow, but light dinghy. We can lift out one or two 5kw batteries separately, which weigh about 110 pounds each.

We can also configure the tender for lighter weight, using just one of the two 5kw batteries if we don't need more range.

Below is the electric outboard option we are purchasing.

Zerojet Electric Outboard

Engine Type: Zerojet electric
Horsepower: 25 hp
KW: 20
Voltage: 48vdc
Shaft Length: 20-22""
Steering: Tiller
Weight: 83 pounds (38kg)
Battery Weight: 120lbs (60lbs.x2)
Top speed (with our rib) 20 knots
Range: At 16 knots, 14 nautical miles.

The best power to weight ratio in electric outboards - no other 48V electric outboards can match the performance of this 20kW (25hp equivalent) electric outboard which can get a RIB like our Inmar onto the plane.

What’s more impressive is that this outboard weighs in at 38kg (83 pounds) and runs on a 48V LifePo4 architecture. It’s safe for all marine enthusiasts.

It is also belt driven! That means, no metal shafts, gears, or differentials needing oil! And, no interior salt water cooling. So, you don't have pump fresh water into the inside to rinse this motor after use.

All total, outboard, batteries, and Inmar RIB, our Tender configuration will weigh: 83+120+185 = 388 lbs.

Below are the two gas outboard options we considered before deciding on the Zerojet.

Yamaha F25

Engine Type: Yamaha F25LWHC Four Stroke
Horsepower: 25 hp
Cylinders: 2 cyl
Shaft Length: 20"
Steering: Tiller
Starter: Electric + Manual
Weight: 137 lbs
Full Throttle Range: 5000 - 6000 rpm
Displacement: 432cc
Induction System: EFI
Warranty: 3 years

Yamaha's 432-cc 25-hp portable outboard sports a new, streamlined, portable design and class-leading power-to-weight. In fact, it's the lightest 25-hp outboard on the water—two-stroke or four-stroke. While its streamlined design is 25 percent lighter, it still packs exciting features like battery-less EFI. Pull-start models can now take advantage of this feature, plus the system is designed with an automatic decompression device to require even less effort for manual starting.

Tohatsu MFS25

Maximum output: 25HP (18.4 KW)
Maximum operation range: 5000-6000 rpm
Fuel Consumption at W.O.T: 8.8 L/Hr
Number of cylinder: 3c
Starting System: Manual
Ignition timing: Electronically Advanced
Alternator output: 12V, 180W 15A
Speed control: Remote Control or Twist Grip
Gear reduction ratio: 1.92
Emission compliance: EU & CARB 3-Star
Advanced cross-flow induction
Canister style oil filter for easy replacement
Larger capacity oil reservoir
Tuned intake system for crisp takeoffs
Ultra Low emission, EPA and CARB approved
5 Year limited warranty
Electronic fuel injection
The boating industry's first battery-free, manual start EFI 4-stroke
Digital CD ignition system for quicker starts
Adjustable steering friction and trim tab for reducing steering effort
Front mounted shift lever for easier operations

"The all new MFS25/30D model is the lightest 3-cylinder in its class. The revolutionary design allowed for a dramatic weight reduction without sacrificing high performance levels.
Unique to the MFS25/30D, Tohatsu has redesigned the tiller handle to include a stop switch, a four-step trolling speed control system starting at 750 RPM, forward - neutral - reverse shifter, and throttle friction adjustment. Certain models also include electric start button and power trim and tilt switch. Tohatsu's multi-function tiller handle is also available for multiple model options. The multi-function tiller handle is equipped with 3-position height adjustment with optional accessory to provide an additional 4-position height adjustment. Both standard and multi-function tiller handles have trolling speed control feature.

Below are the the other electric outboard options we considered,

(though we are now selling our Stealth e18, for reasons, see below)

Stealth E18KW specs

* 18 kW continuous power (but at 96v, at 48v it only gives us 9 kw)
* 23 hp gas equivalent (11.84hp at 48v)
* 48 - 96 volts
* Weight 84 lbs. (actually more like 100 pounds with control box)
* Speeds up to around 15 mph for at least an hour (but at 48v maximum speed was 6.5 mph).
* Yamaha lower leg for easy part replacement.
* Water cooled
* Motor price: $5,795 ($6,484 with shipping from Texas to California).

We did not choose to buy the Stealth Electric Outboards NMC batteries. Instead, we went with cheaper DIY LifePO4 batteries we designed. The two LifePO4 batteries, all total, they cost us about $3,000, which is around $2,500 less than the Stealth package (motor plus battery).
The Stealth E18KW weighs 100 pounds with control box plus our 230ah 48v LifePO4 safer set of two LifePO4 batteries weigh 100 pounds each.

Sea Trials and the problems with this outboard:
The outboard can use 48v so we tested with two of our 24v batteries put in series to get to 48v. Those plus the motor and tender weigh 495 pounds.
What we discovered is that you really need to purchase the 96v batteries to get the full speed out of this electric motor.

Zero Jet

* Controls: Tiller
* Power input/output: 14kW / (19 hp)
* Nominal voltage: 48 V
* Weight: 85 lbs.
* Jet propulsion
* Price: $35,000 with proprietary battery and Highfield RIB

Zerojet's outboard is a nice option, but it would not be removable. So, since we would like to convert our tender to a dinghy at times for beach surf entries, this would not work out for our needs. (But they have a new option, the Zerojet outboard (see above).

Epropulsion Spirit 1.0 Evo (we are keeping this outboard)

* Input Power: 1 kW
* Equivalent Horsepower: 3hp
* Motor Weight: 24 lbs.
* Battery Weight: 19.4 lbs.
* Battery Capacity: 1018 Wh
* Tiller Control
* Run time: 75 min to 4 hours, depending on power usage
* Range: 46.8 nautical miles at 2.3 knots or at full speed, 5.1 knots for 6.4 nautical miles.
* 48 volt (will also run off of our other battery pack).
* Price: $2500

NOTE: The Spirit 1.0 Evo is for short trips where we don't need speed and will also be used when we want to beach the dinghy. In that case, we remove the bigger main outboard and batteries and go with this small electric motor we shed about 203 lbs, adding the Spirit 1.0 Evo back in, it means our Dinghy configuration weighs 24+19.4+185 = 228.4 pounds. The Spirit is waterproof, so if we get doused by a wave in the surf, that is no problem and dragging it up the beach on the wheels we are installing will be a breeze.

As a backup to the main outboard, the Spirit can also be brought on board the tender. In an emergency, the Spirit can motor us back to the mothership. The trip might be slow at 5 knots, but slow is better than stranded.

We also have two batteries for extending the range to 150 minutes at full throttle ( which means 2.5 hours and a range of 12.8 miles).

There is a new feature with the Evo model, they have added hydrogeneration. Of course, this is a small amount of regeneration; at maximum, we will be getting around 300 - 330 watts an hour. Still, if we mount this to a sugar scoop while on passage it will be able to recharge its own battery.

Our conclusion on tender motors

The new Zerojet electric outboard is exactly the option we were seeking, and we have put down a deposit on purchasing this new outboard.

Dinghy Chaps

What are Dinghy chaps for?

Chaps
With Hypalon material tubes dinghy's can last about 10 years even in harsh tropic sun conditions. However, that doesn't mean they won't start to look a little dull and worn out over time.

Also, abrasion from lines or other things, like dragging scuba gear in and out, can damage the hypalon.

To the rescue come dinghy chaps! These are a cover you put over the tops of the tubes to protect them from abrasion and UV damage. With Chaps, we hope to extend the life or our dinghy for the entire double circumnavigation.

Where can you get chaps?

Where do you get chaps?
Unfortunately, due to variances in the locations of mounts and other protrusions, dinghies are not exactly the same. Therefore, chaps are not mass produced. That leaves two ways for us to get Chaps:

1) Hire someone, or a company, to custom make the Chaps by letting them have our dinghy for a time while the Chaps are created. This typically costs $2,000 or more!

2) Make them ourselves. Though far less expensive, this option does require us to own a sewing machine capable of sewing through multiple layers of thick UV resistant materials. However, we already plan to purchase such a machine for sail repairs and other needs. So, now it is just down to the knowledge and labor of sewing these chaps. Fortunately, there are 'how to' videos available, so that covers the knowledge, so we just need to set aside the time. Fortunately, two of our crew members are good at sewing!

Boat Wheels

Why do you need boat wheels?

These help you pull a relatively heavy dingy up onto a beach by letting wheels take up a large portion of the weight. The wheels are mounted to the outside of the dingy transom. When not in use, they can be retracted upwards so that they don't drag in the water. When approaching shore, the wheels can be extended down so that you are ready to pull the boat up on to the beach.

Here is our choice for boat wheels for our dinghy:

BeachMaster

* The Patented BEACHMASTER Autolock system is light and strong as well as being extremely fast, easy and clean, and may be operated without touching the wheels.
* Beachmaster boat wheels unique over-center locking mechanism compactly encapsulates and locks the wheel against the transom when retracted, then extends in use to form a cross braced frame for high strength in all directions.
* They are designed to be used with outboards in shallow water drive mode so they can be operated close to shore.
* Their very fast and easy to use auto-locking action up and down is an essential feature for launching and landing on surf beaches and fast flowing rivers or when conditions afloat are rough.
* A reassuring click instantly lets you know the wheels are securely locked home in both the up and down positions.
* The retracted wheel is locked and prevented from spinning which provides a secure handhold for safety when working around the outboard.
* The easy to reach non-jamming up-and-away motion of the mechanism enables the wheels to be deployed and retracted in the shallowest possible water. Beachmaster dinghy wheels are not jammed by the buoyancy of the tire or grounding as can be the case with other systems.

* The low visual profile and compact retracted position of beachmaster dinghy wheels against the transom allows for normal unhindered operation the boat and outboard motor. The wheels are quiet and smooth running and are large, quality, Nylon reinforced, 4 ply rated pneumatic tires (10.5" diameter) with polypropylene rims and nylon bearings for durability in marine environments, using Butyl tubes for reliability.
* Being self contained there are no separate parts to stow or lose or pins to fit. They are always instantly ready for action.
* For strength, durability and light weight the wheel system is manufactured with marine grade boat building Aluminum.
* The mounting bracket measures 5.5" x 8" and is effectively designed to distribute the wheel loads to 4 widely spaced bolts.

Specs on the BeachMasters

* Recommended for boat lengths up to 12 feet. (3.6 m) [ours: exactly 12']

* Recommended for gas outboards up to 15 hp which weigh about 85 pounds. Our electric outboard is: 20 hp, but it only weighs 85 pounds, but more of the time we are beaching the boat we will be using our 3 hp, 43.4 ePropulsoin Spirit 1.0 Evo!

* Maximum load limit 440 lbs (200 kg)/set on hard smooth surfaces for both fixed and removable mount types. Our heavy version of the dinghy weighs: 480 pounds (with full tank of gas), but we would rarely, if ever, be on the hard with our dinghy in this heavy configuration. Our light version weighs 244 pounds.

* Recommended tire pressures 5psi (soft surfaces) to 15psi (hard surfaces).

* Mount Weight: 10.5 pounds (4.8 kg) per set of two.

Conclusion on Tender Wheels

We looked at all the options for wheels to beach our RIB and the clear choice for quality and function are the Beachmaster wheels. Their is even an option for a removable mount, which we went with since it offers us some options in configuration. We posted a video about mounting the wheels and will put a review video of the Beachmaster Wheels once we get to sea trials early in 2023.

INFORMATION

About us
News
Get In Touch

Help us out

Subscribe Youtube
Join Patreon

Subscribe to our Youtube or Patreon

Please consider subscribing to our Youtube channel, it really helps us out! To subscribe, click the Youtube link (left). Or, we would love it if you became part of our Patron Crew, with all the perks! Link is also (left).

‌

AI Website Generator