Bunk width for Zodiac MkII

[Durhampro]

I am still new to inflatables, in fact I don't have mine yet. I recently purchased a Futura MkII that was in need of a new transom because it was cracking and the glue was coming off the transom seams. ( I am not complaining, I knew what I was getting into when I purchased it ) I currently have the trailer in the driveway and the boat is being repaired but as I look at the two trailer bunks they seem pretty wide I believe that only the tubes are being supported. This boat has a 50hp motor on it and the previous owner had added a homemade transom support to the inside of the boat. I believe he did that because the motor was destroying the transom when it was being trailered.

Should I add an additional set of bunks to support the transom and should I be using a transom saver when trailering to prevent future damage?

[SixtyNorth]

The transom needs supporting when using a trailer with the outboard fixed in place. The general consensus here seems to be to have the bunks support the boat at the point the floor meets the tubes, if you only have one set of bunks. Then a 3rd bunk under the keel and a transom saver of some kind to take the weight during transport and reduce the flexing/ movement.

[_monkey]

Futuras seem to be popular in Netherlands, consequently trailer manufactures offer variants for soft hulls, which seem to do a good job of supporting a SIB and have transom savers;

[SixtyNorth]

The trailer in that photo looks like an interesting alternative to a bunked trailer. Who sells those trailers?

That said, I think full length bunks still provide better support for an inflatable boat and distribute the weight over a larger area, reducing stress on the tubes.

Although the transom is supported on the trailer in the photo, a transom saver would still be a good idea to reduce engine movement and therefore stress on the transom/ tube bond. The transom saver would support the outboard leg, connecting it to the trailer separately. They are simple to use.

[_monkey]

Originally Posted by SixtyNorth

The trailer in that photo looks like an interesting alternative to a bunked trailer. Who sells those trailers?

That said, I think full length bunks still provide better support for an inflatable boat and distribute the weight over a larger area, reducing stress on the tubes.

Although the transom is supported on the trailer in the photo, a transom saver would still be a good idea to reduce engine movement and therefore stress on the transom/ tube bond. The transom saver would support the outboard leg, connecting it to the trailer separately. They are simple to use.

Yes, I meant transom support - are transom savers popular in the UK?

The trailer is made by Pega - NL company;

Pega Boottrailers

[SixtyNorth]

Thanks for the link!

I am not sure how popular they are here, I made one myself once, for a Zodiac Grand Raid with a 30hp outboard. They are very simple but effective.

[Durhampro]

Originally Posted by SixtyNorth

The transom needs supporting when using a trailer with the outboard fixed in place. The general consensus here seems to be to have the bunks support the boat at the point the floor meets the tubes, if you only have one set of bunks. Then a 3rd bunk under the keel and a transom saver of some kind to take the weight during transport and reduce the flexing/movement.

That's what I thought, the damage to the transom in my opinion was caused by the stress the motor caused when trailering.



If you look at the left side of the transom you can see how it is bent, that is where it is cracking. The company that is repairing the boat is building a whole new transom.

The solution the previous owner used was a pair of reinforcement bars on the inside of the boat. I believe he did that after the transom began to sag and then crack.



Great info gentlemen, thank you very much. I still have a week or so before my boat comes back from the repair shop and I will be adding more support to the trailer because I don't want to repair it twice.

[cgoing]

Generally under inflation is a huge cause of that too. I've seen a few left under inflated and which adds undue stress on the transom joints. Best to keep them fully inflated and store bow raised so water drains properly. Also ensure that any bolts used for fastening the motor are well sealed to prevent water intrusion which will start to degrade the transom faster.

[office888]

CastleCraft Trailer for Inflatable Boat and RIB | Trailex Trailers for Inflatables and RIB

This is my favorite North America trailer for large SIBs.

The transom failure was a combination is large stresses, under inflation, and weak glue.

[Northern Pike]

This is the trailer I built: