Clayton H. Accident

Eddyj · Aug 24, 2018

If it's your first post you should make it a good one. You did

the_white_shadow · Aug 24, 2018

Great first post Jeff. For a recreational wheeler that doesnt race in any fashion (besides in their head on the fire roads), what type of seat would you recommend? Im using PRP suspension seats now due to how comfortable to me they are. Would you recommend something different?

tiny · Aug 25, 2018

This is for the shoulder harnesses that are coming loose. It does make it more difficult to adjust, but they do not loosen.
https://www.summitracing.com/search/product-line/g-force-seat-belt-anti-slip-springs

Jeff Furrier · Aug 25, 2018

A good quality suspension seat is fine in lower speed recreational vehicles if the seatbelts are set up correctly. Higher speeds mean higher G forces impacts, so being restrained with minimal movement. PRP and Mastercraft build a good suspension seat for recreational use.

A set of SFI approved belts that are set up properly, should come loose to the point where they are unmanageable to keep tight. One of the reasons belts come loose is when they are pulling down on your shoulders, every time you hit a bump you bounce against them they slowly will start to come loose. If your shoulder belts pull you back, the constant forces from beating around in an off road car are much less.

One thing that works for me is to loosen your belts before you take them off so the adjusters to create a kink in the belt that you constantly have to fight when putting them on. You have to loosen them when you get in anyways, just do it before you get out. A belt that sits for days, weeks, months is a PITA to move as we all know.

Also, using an air hose to clean the belts is way better than water. Water and dirt packs the material up and makes it stiff.

tiny · Aug 26, 2018

From the eyewitness account, it sounds like the g force was in the forward direction and not downward like we predicted. I've been looking for videos that show how the shoulder harness was mounted. 35 seconds in.
https://m.youtube.com/watch?v=_dUuGQIciI0#fauxfullscreen
I think it is important that this kind of information should be shared to prevent future injuries.

poolman · Aug 26, 2018

tiny said:
From the eyewitness account, it sounds like the g force was in the forward direction and not downward like we predicted. I've been looking for videos that show how the shoulder harness was mounted. 35 seconds in.
https://m.youtube.com/watch?v=_dUuGQIciI0#fauxfullscreen
I think it is important that this kind of information should be shared to prevent future injuries.

Thats the 4 cylinder buggy. Was he in it or the Outlaw #1?

Jeff Furrier · Aug 26, 2018

I watched a few videos, I can't really tell but would speculate that the cross bar behind the seats which is 10 inches or so below his shoulders from the angle I saw. This is a problem if it where they are mounted. This is super common because that bar is the most obvious place to mount the harness and it already in about every chassis on or off road. The problem is you are not being held back so you can roll forward in harness, as you go forward and the harness tightens, it compresses your spine. It's pretty common that you break your back at your T12 vertebra.
If your shoulder harness are mounted below your shoulders because this bar is too low, add another bar.

The other problem I see is that the seat has no side shoulder supports, but has a side head restraint halo. This isn't a combination that is being recommended by any seat manufacturer that I'm aware of.
You don't want your head and neck restraining your whole body in a side impact, that's your torsos job. The side head restraint is only supposed to support side movement of your head. This combination with an improperly mounted shoulder harness is a recipe for disaster.

Poke · Aug 27, 2018

TBItoy said:
have you ever used/seen the ratchet tight belts?
That's the only way I could get laps tight enough.

Before that I had PRP make me some "pull up" belts, where you pull UP on the laps to tighten. I could brace my feet and push myself back into the seat (Corbeau XP) really hard and tighten them down pretty good.

I dont think ratchet belts are Ultra4 approved, No.

I like the pull up style.

Poke · Aug 27, 2018

Bebop said:
No-one runs suspension seats. Everyone runs Sparco type seats, which are a hard shell with some sort of foam at the bottom.

This is an inaccurate statement. It's a mixed bag that might favor suspension seats.

TBItoy · Aug 27, 2018

Poke said:
This is an inaccurate statement. It's a mixed bag that might favor suspension seats.

In the Dakar rallye vehicles?

Bebop · Aug 27, 2018

I'd be curious to see an example of a Dakar vehicle with suspension seats.

Jeff Furrier · Aug 27, 2018

Dakar is sanctioned by the FIA, so the seats are required to be FIA approved. Sparco has a suspension style seat(Sprint) that was approved years ago, but I've never seen them in a racaecar or would I recommend them. There are no FIA approved US built suspension seats that Ive ever seen and I would doubt they could possibly meet the current spec, mostly because of the steel tube frame wouldnt pass the current load tests.

In 2002ish Larry Ragland went to Dakar with a Pro Truck equipped Mastercraft suspension seats, they couldn't get through tech without refitting the truck with Sparco Pro 2000's. Larry is the one that got me to recognize that value of the shell style seat and we've been educating off road guys ever since.

jeeptj99 · Aug 27, 2018

Dude makes 5 posts and has more tech/education in it than most have in 1000. This is all interesting to read and learn, makes me question how my belts and seats are set up if they are correct (not that i'm a racer/bouncer but would like to know i'd be good in that oh **** moment). Keep it up :dblthumb:

tiny · Aug 27, 2018

@ Jeff Furrier. What do you think about tbitoy's idea of a containment seat with suspension? the harnesses would have to be part of the seat, pivot on the front so your legs stay put.

Jeff Furrier · Aug 27, 2018

Its been done, Mickey Thompson was doing it in the 70's. I think there's probably a way to do it ans we spent some time with short Fox Mountain bike shocks trying to come up with something but could never make make it work properly. The only time it would really work would be with vertical forces, no real side to side benefit.
The way our seat pad is designed is with 2 foam densities, the top is soft and the bottom is very firm so it slows you down before you stop..like a bi-pass shock for your ass as we describe it. The second and third hits are probably the most dangerous as at that point you are out of position in your seat. I watched a few videos of what you guys are doing and honestly the movements are way more violent than anything I see in traditional off road racing, so seat belt positioning is really key.

Sit in your cars and tighten your belts, laps first as tight as you can get them, then the same with your shoulders. When I say tighten, I mean until you cant move forward in the seat. If you're shoulders hurt from the harness to the point you want to loosen them, loosen them to where you're comfortable and try to move forward. I'll bet most of you can move forward a bunch with the adjustment at a comfortable level. Think about how much more they will loosen when you start bouncing around? When you hit something and your truck/buggy stops you slam against the front of your belts, then your head whips forward. If your belts were tight, you'd just gradually stretch the belts without the hard stop at the end. Chris from ISP uses the term "If you cant swing the hammer, you cant drive the nail". I do a demo with a piece of scotch tape looped through a 10lb weight, the tape holds the weight until I pull up and drop it..then it turns into 50lbs and brakes the tape.

If your harness are pulling you back becasue the mounts are close to level with your shoulders, the force from the belts is mostly on your chest so its way more comfortable and an immeasurable amount safer.

While your shoulder harnesses are tight, your sub belt should be tight and the lap belt should be below your belly button. If tightening your shoulder harness raises your lap belt, the sub strap is too short. Most people have the sub belt too long becasue it makes it easier to put on, but if its too long your belts will never be tight. If you have a couple people in the same rig that need different lengths, use 2 sub belts.

The "Anti-Submarine" belt isn't to keep you from sliding out from underneath the lap belt, its to pull against your shoulder harness to keep it tight.