How to determine the lengths of your bunks??

[CrewCabMax]

I'm going to be starting to round up parts for my boat trailer here soon. How do you guys determine how long your bunks should be?? I have a 17' v bottom, and want to make sure its got plenty of support. This guy will be making many 100+ mile trips to Lake Erie and back, so I want to make sure its safe of a trailer. Thanks!

 

[bassboy1]

I go as long as I practically can given the location of the crossmembers of the trailer, and the curvature of the hull. A bunk is useless if it extends much past the cross members, so extending them forward of the cross bar is pointless, and you can only bend a bunk so much, practically, so when it gets to the point that the boat slopes upwards, there is only so far you can go.

 

[ben2go]

Make sure the transom is supported so it doesn't develop a hook.