For you to truly feel the adrenaline rush of water tubing, you need a boat with a sufficient amount of horsepower to pull you through the water with enough speed. But what is the proper amount of horsepower required to pull a water tube exactly?
A boat with horsepower at or above 60 would be sufficient to move at speeds near 15 mph when towing a water tube with a single rider. To tow more riders, the boat may need a horsepower at or above 90. These are not definitive guidelines, though, as heavier boats require more horsepower.
When it comes to water tubing or any other water-based activity that requires a boat for towing, the boat itself should be powerful enough to tow the person through the water. Nevertheless, even though horsepower is the primary factor in determining the speed of a water tube, other factors need to be considered. Read further to learn about the various factors that influence the horsepower necessary for water tubing.
Ideal Horsepower for Water Tubing
Water tubing is one of the most popular water-based activities because there isn’t a considerable degree of skill involved. All that a person must do is hold on tightly to the tube handles, lay back, and relax. There’s very little strength, balance, or coordination involved, especially when compared to other water-based activities.
While water tubing may not put a great deal of stress on you, it does put a great deal of stress on the vessel pulling it. The boat that’s towing the water tube needs sufficient power to pull it at adequate speeds. This begs the question, “What exactly is the ideal horsepower to do this?”
Unfortunately, the answer to this question is not so clear-cut as it would seem. There’s an assortment of variables that need to be considered when trying to pin down the ideal horsepower that a boat needs for an enjoyable water tubing trip.
The foremost factor you have to consider is the number of people that plan to tube at any one time. The more people that the boat needs to tow, the more horsepower it will require.
When only one rider needs to be towed, the horsepower requirements are not too substantial. As we touched on earlier, 60hp is a solid benchmark for towing a single rider. With an engine capable of such power, the boat will reach speeds close to 15 mph, which is ideal for water tubing.
A boat capable of 70 hp is largely considered more than enough for water tubing, particularly when dealing with a single rider (source). To give you some perspective, the recommended horsepower minimum for water skiing is about 70 hp to move at speeds up to 20 mph (source). Since water tubing requires slightly less speed relative to water skiing, it makes sense that the horsepower requirements are slightly less.
The question of horsepower becomes a bit more complicated when you want to add more riders to the equation. A boat with a 60hp engine may be enough to tow a single person (or possibly two lightweight individuals), but it may lack the power to pull any more riders than that.
When towing more than three individuals at a given time, the boat will typically need to have an engine capacity of 90 horsepower at the very least. This is because the boat must exert double or triple the force to reach satisfactory speeds on the water.
If there’s not enough horsepower, the tube will trudge through the water instead of skimming across the water’s surface. A lack of speed may cause the tube to “swamp,” or dip slightly below the water’s surface while still maintaining some semblance of buoyancy (source). Not only is this less enjoyable for the tubers, but it also increases their chances of falling off the tube.
It’s worth bearing in mind that these horsepower numbers are not exact. Since there are so many additional factors that affect the horsepower needed for water tubing, it’s tough to pinpoint an individual boater’s specific needs.
To better grasp where your horsepower requirements stand, it’s in your best interest to take every one of these factors into consideration. The last thing you want to do is commit to a boat that lacks the horsepower needed for what you aim to do on the water.
Factors that Influence the Horsepower Needed for Tubing
As we’ve already established, you should take the 60hp and 90hp baselines in a general context rather than a universal context. You will have to fine-tune these general guidelines to your personal boating needs by considering the following variables.
Type of Boat
Not all boats are made to be equal in terms of water tubing. Certain boats are better tailored for water sports relative to others.
For example, a pontoon boat with a good 70hp engine is not necessarily the same as a jet boat with a 70 hp engine. This is because these two water vessels are constructed for entirely different purposes, so they have designs that are so different from one another.
Plus, the boat design may contribute to vast differences in structural weight. Some water vessels tend to be heavier than others, regardless of how much horsepower they have. Naturally, a heavy 20-foot boat with a 90hp engine will likely not perform at the same level as a lightweight 10-foot boat with a smaller 70hp engine.
Ultimately, it comes down to the type of boat you decide to use. Form equals function, so you can bet that this contrast in boat design would also be reflected in the differential nature of the water tubing trips.
Design of Tube(s)
Aside from the type of boat, the design of the actual towable tubes themselves also plays an influential role in horsepower needs.
In terms of weight, towable tubes are not all that heavy, especially when compared to the weight of the riders. There are exceptions to this rule, however. In some cases, they do have enough dry weight to affect horsepower requirements.
Not all tubes are made from the same material. Certain water tubes are made with heavier, sturdier materials to improve tensile strength. As such, these heavier tubes may require slightly more horsepower to run at average tubing speeds.
Other than weight, towable tubes also vary in the amount of surface area that contacts the water. This significantly affects how much frictional drag the boat must overcome when towing these tubes along the water. Generally, a larger tubing surface area equates to more frictional drag.
All things considered, most boats that have a 60hp engine should be able to tow a standard water tube without many issues. Though, you may want to consider upping the horsepower of your boat engine if you plan on towing:
- multiple tubes simultaneously
- tubes that are heavier than average
- tubes that experience a high amount of frictional drag
Weight of Passenger(s)
In the grand scheme of things, the design of the water tubes is somewhat negligible compared to how much of a difference the weight of the passengers makes. A boat engine must work considerably harder to tow heavier riders at adequate speeds.
For example, towing three lightweight children on a water tube is not the same as towing three full-fledged adults on a water tube. Your horsepower needs will be much greater for pulling the adults than the children because of the vast weight difference.
The riders on the tube are not the only passengers you need to worry about. The passengers on the boat itself may also influence horsepower demands.
In short, you should invest in a stronger engine if you plan on taking on a crowd of passengers—both on the tubes and on the boat—to make your trip on the water an enjoyable one.
How Fast the Tubers Want to Go
This last factor often goes overlooked, but you also have to consider the risk tolerance of the people you plan to tow on the water tubes. Certain people like moving at high speeds on the water, while others want to take a slow, leisurely ride.
Depending on where your tube riders fall on the risk tolerance spectrum, you have to decide whether or not more horsepower is needed.
If you have a relatively young age group that wants to tube, you likely don’t need a maxed-out boat engine to make their time on the water memorable. Moving at speeds of 8 to 12 mph is plenty for young children.
On the other hand, if you’re towing around a group of thrill-seeking teenagers or young adults, tubing at speeds of 8 to 12 mph might be a bore. So you may need a boat with more horsepower to tow them along at higher speeds, between 15 and 20 mph.
You can learn more about how fast to go with your boat for the purposes of water tubing by clicking over to Best Boat Speed for Towing a Water Tube (Solved).
It’s always smart to ask the people who plan on tubing where they stand on the matter. That way, you can get a solid indication of what sort of tubing speeds they want to go.
How to Tell if You Lack the Horsepower Needed for Tubing
As a general rule of thumb, your boat should have approximately one horsepower for every 40 to 25 pounds of weight (source). This may require a bit of calculation on your part, as you have to do some rough estimation as to how much your boat weighs with all its gear, along with the approximate weight of your passengers.
For example, a 3,000-pound boat plus an extra 1,000 pounds in passengers will need somewhere between 100hp and 160hp. This is a fairly wide range, but it’s a reliable starting point to help you narrow down your engine selection.
If these calculations seem like too much of a hassle, you can always just take your boat out for a spin and experiment yourself. In the best-case scenario, your water tubing experience will go without a hitch. But, on the other hand, there’s a chance your boat may struggle to top speeds above 15 mph.
If your boat engine struggles to reach adequate speeds with water tubes in tow, you likely just need a more powerful engine.