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Old 15 July 2015, 18:17   #1
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Trailer nose weight

hi, when I bought my Rib it had none or very little nose weight,by adjusting bunks and winch post and moving rib forward I got it to a reasonable weight. I now want to fit a skimming transducer but because the boat is further forward the transducer is fouling the bunk.
Would it be ok to move boat back so transom is not going up as far as bunks,adjust the winch post and shorten the trailer to achieve a decent nose weight?
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Old 15 July 2015, 18:52   #2
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You could just fit an adjustable transducer mount and simply slide it up out of the way when needed. The weight on the front of the tow-ball should be around 10% of the whole rig weight ie a 1 ton boat outfit should be putting around 100kg of downward force on the hitch easy to test with bathroom scales if your setup isnt too big. (or so Ive always been told)
Jon
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Old 15 July 2015, 19:13   #3
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You need hitch weight, can get twitchy without..
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Old 16 July 2015, 03:16   #4
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Can't you shorten the bunk? The face of the transducer only needs to be around 6mm lower than the hull. I'd be looking at curing the problem at source rather than upsetting the whole rig. That's curing one problem & creating another.
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Old 16 July 2015, 03:53   #5
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Move the axles back to achieve the nose weight, that has the same affect as moving the boat forward be a shame to start cutting lumps off the trailer
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Old 16 July 2015, 03:56   #6
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Quote:
Originally Posted by beamishken View Post
Move the axles back to achieve the nose weight, that has the same affect as moving the boat forward be a shame to start cutting lumps off the trailer
That's the one. :thumbup:
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Old 16 July 2015, 04:36   #7
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Quote:
Originally Posted by jonp View Post
The weight on the front of the tow-ball should be around 10% of the whole rig weight ie a 1 ton boat outfit should be putting around 100kg of downward force on the hitch easy to test with bathroom scales if your setup isnt too big. (or so Ive always been told)
Jon
So a 3.5 tonne trailer has around 350 kg on the hitch

Best to look at the car towing rating and the hitch rating to get an idea of maximum load on the hitch.
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Old 16 July 2015, 05:12   #8
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I must admit I've never used scales to measure the nose weight on my SBS trailer. I fitted a slider to lift the transducer out of the way and tend to load the boat for the holiday by checking with a frequent lift at the front. I did move the axle and winch post to provide probably 20 lbs of positive weight at the front but if I fill the petrol tank I add another 120 Kilos !
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Old 16 July 2015, 05:38   #9
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Max nose weight on the average family car is 75KG, I personally aim for 40KG so it's manageable.
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Old 16 July 2015, 10:27   #10
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Tongue weight should be in the 7-10% range. Too light, and the trailer becomes unstable while towing; too heavy, and you load the tow vehicle too much (which isn't much of a problem on heavier vehicles, but can affect steering near the TV's limit.)

As Beamishken said, if you can't move the boat, move the axle.

jky
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