Don’t blow us off immediately. Let us explain.
We know it happens. You see people out on the lake pulling inflatables with their tower all the time. Yes, most towers CAN do it, but let us inform you why you shouldn’t.
The biggest problem with towing tubes, or other inflatables, with a wakeboard tower is the multi directional forces that are applied to a towers tow point that just aren’t as rough when used with a wakeboarder. Its not a question of “will it rip the tower off of a boat?” If the tower is installed correctly and the proper backing is applied (if needed) you won’t have a problem with that.
THE NO.1 REASON why tower manufacturers stipulate not to tow an inflatable with the tower is not so much the integrity of the tower, but the hull of your boat. Most wakeboard towers are thoroughly engineered for the forces that come from a wakeboarder, not for an inflatable.
Sure, you might not notice much the first time, or even several after, but you will.
Often when you see gel coats cracking it is not from a bad install (some are, don’t get us wrong) but from misuse of the tower.
Wakeboards, skis, kneeboards, etc. almost always create less line load than a tube, especially a muti-rider tube. Wakeboarders like to play in the wake, so they typically don’t create large side loads.
Let’s take this 4-person Tube rope from Overtons. The breaking point on this rope is 4,100 pounds.
Most wakeboard ropes don’t generally give a rating for a breaking point, but do state the rope is intended only for towing a single person on water skis, wake/kneeboards, or barefooting. Any other use may cause rope failure.
This Proline Wakeboard Rope from Overtons shows that is provides 2,000 pounds tensile strength. That is less than half of an inflatable rope.
So, lets take a moment to think about that.
Your out having fun, whipping the tube from side to side. Hit a good wake and the tube takes a nose-dive! BOOM! Rope busted! You just transferred 4,100 pounds (or more) to the tower, which in turn was transferred to the hull of your boat. NOT GOOD! That is a lot of stress that was created just in that one moment.
Let’s do a little math…if a submerged tube can create enough load to break a rope at let’s say a conservative number of 2,000 lbs and say the tower is 5 ft tall above the hull. A simple torque calculation shows that 2,000 lbs x 5ft would create a torque moment of 10,000 ft-lbs on your boat hull. Yes..that’s right 10,000 ft-lbs!!! Even if we disperse that load over each tower mount by 4 , we still see a load of 2,500 ft-lbs. Now do that same math for a wakeboarder. A max load would likely be 200 lbs… thus creating a max torque load of 1,000 ft-lbs. Then divide that by 4 and you get a reasonable torque load of 250 ft-lbs…much better!!
You will find that YOU as the driver have a lot more control on how the tube reacts anyway when sticking with the intended rope connection point on the back of the boat. This spot is MADE for tubes or other inflatables.