bow hopping

[petdos]

h34r: Hi to all im new to o/b tunnels ,having fun trying to set this thing up ,but what causes bow hopping ,and whats the cure thanks,peter.(boat is a bandit-t/t 3.5)

 

[Mark Poole ModVP]

I have never set up a Bandit boat but there are several things common to setting up any tunnel hull. Check the center of gravity, should be around 30 to 33% forward from rear of boat. Some boats need more some less. If the motor is trimmed "up" or "positive" then tuck it down a degree or two. Prop choice will affect the ride of the boat. An X series octura has very little lift which means it does not lift the rear of the boat. A 1440 does lift but that prop requires some knowledge of how to tweak it for use on a tunnel. It could also be as simple as adding several ounces of ballast at the front of the boat. Beyond these, check to make sure the last 6 to 8 inches of the sponsons are not "rockered". They should be straight. Check with a straight edge. Also check to see that the trailing edge of both sponsons are nice and sharp, not rounded.

Mark