Winch and Tie Downs

Hey guys, new to the Tundra community here. This is my first truck as well, so if I ask any dumb questions that would be why..

I'm using my truck to haul motorcycles around. I have a temporary winch setup towards the front of the truck bed with a thick chain connecting the two tie downs in each corner; I then have my winch directly hooked in the middle of the chain to pull the bikes up the 10ft ramp that I have off the tailgate creating a triangle like pulling effect. The chain, winch, and bolts I used are more than capable to secure the load, the only variable in question are the tie downs in each corner. I read the Working Load Limit of each tie down is roughly 220 lbs; however with a chain spreading the load between the 2 tie downs, is it safe to continue using the winch that way. Most of the bikes weight 450-600 lbs- with an occasional 800 pounder. Do the wheels on the motorcycle play a factor in determining the working load limit? The rings seem sturdy but I would hate for one to pop off while I am winching a bike up. The incline of the ramp is not that steep either being its a 10 ft ramp; I would say about 30 degrees incline.

and no I do not want to use a trailer or permanently bolt the winch to the truck; I need it to be able to be removed. The picture attached is where I got the idea, only difference is I am using a chain and the bolts in the corner of the bed. Thank you guys in advance!

 

You have a corded control that allows you run the winch and stabilize the bike so it is a one man operation. That's your whole idea. Right?

So if you're winching up a 1999 Yamaha R1 I'd say you're good to go. If you're winching up a Fat Boy or Goldwing............well, you'll know soon enough.

Welcome to tundras.com.

 

yes it is a wireless remote...lol I am hoping to not know soon enough.

 

There is a lot of math involved in a real answer and I do not want to do the math right now. The short answer is that when you have angles and tension involved the forces act very differently. For example, a hanging rope with no load on it will have next to zero force on it but to keep that rope perfectly straight horizontally even with no load takes "in theory" an infinite force. If you could hook it up with a rigid connection like a steel bar that distributes equally over the two tie downs I would say you would be able to just straight up add them. Your ramp does help you because you are not pulling the entire weight of the bike. If you have a 30-degree ramp like you said that means you will only have about half the weight of the bike in tension when the wheels are free rolling. So my answer is it depends on A LOT!!

 

Welcome from NY.

I would bolt that in the bed of the truck. Use wing nuts so you can remove it when not needed. I would not trust that at all. JMO

 

That setup looks very janky. I could not clearly understand everything that is different with your setup from what is pictured but, with the pictured setup, those crapping eyebolts are the weak link. They will start bending before the straps break.

 

For the record. I did something similar. I traveled 500 miles to pick up a Suzuki GSF1200S. 550 pounds of motorbike. When I got to Dudes house in Virginia there had been a snow storm. His driveway was sloped up. The bike......yup....in the garage at the bottom of the driveway. I had tie downs with me (obviously) to tie the bike down in the bed of the T100. But nothing else. So I ran to Home Depot and got a hand come-a-long. Took a cam lock style tie down and strung it between the two front tie town points in the bed of the truck. Wrapped some soft ties around the triple clamp of the Suzuki and come-a-longed that bike up a dirt bike ramp (with Dude's help) into the bed of the truck that was already pointing up hill. I was ready for a Benny Hill style disaster at any moment. But..................NOPE. The whole Beverly Hillbillies contraption stayed together.

Oh. Wait. My lawyer just texted me. Asked me to add: YMMV.

 

One other thing to note is that the working load limit of the tie downs is assuming that you are bumping along the road and actively stressing them. In the static situation that you have in a driveway, with a constant slowly applied force, the breaking limit is probably much higher. I personally would not run it the way you are describing but I can't tell you what to do either. You may be able to run it without issues but as I said before you could get a college degrees with the math involved in whether or not you will break anything.

 

I hope you and the bike owners have good insurance. Those eye bolts and straps look sketchy af. Get a trailer.

 

@APalmTree i appreciate the response, I will have to look into that.

also to others points, the eye bolts I used are weighted for 5000 lbs so they would not have an issue.
@TundraMcGov. lol I’m from VA too! Glad to hear it worked out for you. Must have been a sweet ride.

 

Not getting pulled laterally against each other like that. If used in a way that they are meant to be used, then sure.

 

Eye bolt ratings are at a straight pull in line with the shank of the bolt. And as Brandon alluded to, the load on those straps being nearly 90-degrees to the pull of the winch equates to exponentially more tension than what you are pulling with the winch. The best thing to do to get the winch in that same approximate position but not have the potential for popping a strap or caving in the sides of your bed would be to run an angle iron across the back of the bed. So the horizontal leg is on the top edge of the bed, and the vertical leg is on the inside. Bolt it down to the top of the bed lip, and then bolt the winch to the vertical leg. That will serve to stiffen the back edge of the bed and distribute the load of the winch across the back of the bed.

 

When I said I did not want to do the math I forgot I had access to programs that will do it for me so here goes with visuals this time.

Rope Straight across between tie-downs Approximation. This gives an idea of the infinite force I was hand waving to explain and the exponential force like Casey said with small-angle tension. You can see I moved the middle joint just slightly because the program would not run with a perfectly straight connection because of the infinity problem.



Next is a Rope Approximation with 45 degree pull. This is a much better case scenario if you have to work this way but you lose most of the bed to pull into.




Finally a rigid bar approximation like I mentioned and Casey brought up with an angle across the top of the bed. In this case, the bar bending will limit your system, or if you attach it in multiple places across the top of the bed like Casey said the bending will become a moot point.


Hopefully that make more sense than me just saying "infinite force"

 

An eye bolt rated at 5000 lbs is going to be threaded 3/4"-10. That is a big eye bolt. Are you sure about the rating?

It sounds like you are going to be transporting these bikes quite a bit and as others have stated, a trailer is a much better option. The best that can happen is the bed of your truck gets thrashed when something breaks. The worst that can happen is a 600 pound bike injures you.

 

It's all about angles. You toss the weight ratings away if you use a strap as pictured.
A very simple demonstration.

Hold 50lb dumbbells in each hand with your arms straight down. You can probably stay like that for a long time. Now hold them straight out to your sides, away from your body. You'll keep them there a fraction of the time if at all.

Same weight different force.

 

Okay so it seems like I may have under thought this one. I appreciate all the responses and @APalmTree for that graph(serious skills). I know mounting is best but I’m really not looking to go that route for other reasons. Does anyone have any other suggestion with a similar set up?

 

So awesome

 

My small bit of knowledge to contribute

 

You better have a place to secure that battery. You don't want it bounce or slide around in the bed when you're driving. I was careless about one when I was a teenager and later wondered why I had rust and blistered paint in the bed and on the back of my cab.