The Lotus Cars Community banner
1 - 20 of 29 Posts

·
Registered
Joined
·
116 Posts
Discussion Starter · #1 ·
Hi folks,

I have an 07 S and recently installed Sector 111's Schroth Profi II ASM harness. I am using the stock seat (modified bottom for AS belt).

The shoulder belts are installed on the factory bar and routed through the existing openings. Pretty straight forward.

I tried to use my Hans device today and the belts just felt like they wanted to slide off the sides, and in fact in two of the sessions the left belt slid off. This is not a matter of them not being tight enough.

Anyone has a similar problem? These are 3" belts and should work. Should I try crossing them behind the seat? Or is there something wrong with the hole position in the OEM seats that causes this?

Any tips appreciated, hate driving without one!
 

·
Registered
Joined
·
9,786 Posts
I have the stock Exige seats with a sub slot cut in them, track pack harness bar, Schroth Profi-II 6pt harnesses and a HANS 20L with sliding tethers. I've done 5 track days with this setup, and I've never had an issue with the shoulder belts sliding out of the HANS guides.

A few things you should check:

1) Is the highest point that the harness touches on the HANS above the height of the harness bar? If so, the angle of the shoulder strap from the HANS to the harness bar should be from zero to 20 degrees downward from the horizontal. If not, you've got a serious problem.

2) Make sure when you're tightening down the shoulder straps that the belts are as close together as possible, i.e. make sure as much of the belt is seated on the HANS as possible.

3) Tighten belts as much as you can stand. Then tighten a bit more :D
 

·
Registered
Joined
·
5,094 Posts
1) Is the highest point that the harness touches on the HANS above the height of the harness bar? If so, the angle of the shoulder strap from the HANS to the harness bar should be about 20 degrees downward from the horizontal. If not, you've got a serious problem.
APK,
I believe this is incorrect.
HANS specifies horizontal to minus 10 degrees below horizonal.
if it is too steep, it can compress you spine when it restrains you.

to the original poster; also check that your shoulder harness belts are attached to the harness bar and secured so that they are no more than 3" apart from webbing to webbing.
you can mount a collar on either outside of each to keep them in place, or weld a u shaped bar over each where you want them to mount so that they dont slide.

I am not sure what the deal is with your set up, but fix it before you go back out, you are basically driving with no shoudler harness from the sound of it, and thats bad news.

how about posting some pictures of the set up, mostly one with you cinched up in your seat with the HANS and the harness on. it might show what the problem is.
 

·
Registered
Joined
·
9,786 Posts
APK,
I believe this is incorrect.
HANS specifies horizontal to minus 10 degrees below horizonal.
if it is too steep, it can compress you spine when it restrains you.

to the original poster; also check that your shoulder harness belts are attached to the harness bar and secured so that they are no more than 3" apart from webbing to webbing.
you can mount a collar on either outside of each to keep them in place, or weld a u shaped bar over each where you want them to mount so that they dont slide.

I am not sure what the deal is with your set up, but fix it before you go back out, you are basically driving with no shoudler harness from the sound of it, and thats bad news.

how about posting some pictures of the set up, mostly one with you cinched up in your seat with the HANS and the harness on. it might show what the problem is.
Thanks for the heads-up Fish... I should have said 0 to 20 degrees down... it's now fixed above

I just re-checked the Schroth site:

<b>SHOULDER BELT ROUTING</b>
Shoulder belts must run from the shoulders horizontally or down, at no more than a 20° angle.
 

Attachments

·
Registered
Joined
·
5,094 Posts
Thanks for the heads-up Fish... I should have said 0 to 20 degrees down... it's now fixed above

I just re-checked the Schroth site:
per the HANS site
check the owners manual pdf file pages 6-7.

Resources
Apk,
if you are at 20 degrees its way too steep.
I had a bar welded into my 944 cage after the seat was fitted to the car, and we placed the bar where my shoulder harness would mount at -5 degrees below horizontal.

most of the guys in my 944 group run with the HANS, but use the bar on the standard 944 cage to mount to, and they were/are at about 20 degrees which i believe is what you should be at w/o the HANS device being used.
 

·
Registered
Joined
·
9,786 Posts
per the HANS site
check the owners manual pdf file pages 6-7.

Resources
Apk,
if you are at 20 degrees its way too steep.
I had a bar welded into my 944 cage after the seat was fitted to the car, and we placed the bar where my shoulder harness would mount at -5 degrees below horizontal.

most of the guys in my 944 group run with the HANS, but use the bar on the standard 944 cage to mount to, and they were/are at about 20 degrees which i believe is what you should be at w/o the HANS device being used.
No, not at 20... more like 10... without the HANS it's almost horizontal from my shoulder to the harness bar. I fixed the previous reference, that was in error...

You mean this graphic, yes?
 

Attachments

·
Registered
Joined
·
116 Posts
Discussion Starter · #9 ·
I would suspect an issue with the angle since I'm fairly tall. Will have someone help me measure and take pictures if needed hopefully this week.

But while the angle may be unsafe not sure that it accounts for the sliding.

The belts are not restrained on the bar so entirely possible that they are more than 3" apart, that should be easy enough to address. Somewhat related, what is the thinking as far as crossing them over behind the seat? The bottom of the first picture APK posted makes it look possible (although distance maybe an issue).

Fishguy, at least I was able to tighten the strap directly on my shoulder while on the back straight. After the second time I just finished the day without the Hans.
 

·
Registered
Joined
·
170 Posts
I have an 07 S and recently installed Sector 111's Schroth Profi II ASM harness.

SNIP

I tried to use my Hans device today and the belts just felt like they wanted to slide off the sides,

Are ASM harnesses ok to use with HANS devices? I thought I recall reading something about that not being adviseable...i may be wrong
 

·
Registered
Joined
·
9,786 Posts
I would suspect an issue with the angle since I'm fairly tall. Will have someone help me measure and take pictures if needed hopefully this week.

But while the angle may be unsafe not sure that it accounts for the sliding.

The belts are not restrained on the bar so entirely possible that they are more than 3" apart, that should be easy enough to address. Somewhat related, what is the thinking as far as crossing them over behind the seat? The bottom of the first picture APK posted makes it look possible (although distance maybe an issue).

Fishguy, at least I was able to tighten the strap directly on my shoulder while on the back straight. After the second time I just finished the day without the Hans.
Download this document: http://www.schrothracing.com/docs/Competition_Instructions.pdf... there are detailed instructions for how to restrain the shoulder belt ends, and how to properly route the belts over a HANS device:
 

·
Registered
Joined
·
1,032 Posts
I HAVE OLD INFORMATION HERE SEE BROKENBOY's POST BELOW,

Are ASM harnesses ok to use with HANS devices? I thought I recall reading something about that not being adviseable...i may be wrong
I believe that your correct, HANS + ASM is a bad idea:

this directly from the HSM Motorsports site:

"You can add a single or dual sub strap to make this belt into a 5 point or 6 point at any time. The only thing you cannot do with this belt is use a HANS device. The HANS device and the 3" ASM have not been tested together."

Schroth Competition Belts // Profi ASM 4 Point Harnesses // Profi II ASM // HMS Motorsport
 

·
Registered
Joined
·
9,786 Posts
I believe that your correct, HANS + ASM is a bad idea:

this directly from the HSM Motorsports site:

"You can add a single or dual sub strap to make this belt into a 5 point or 6 point at any time. The only thing you cannot do with this belt is use a HANS device. The HANS device and the 3" ASM have not been tested together."

Schroth Competition Belts // Profi ASM 4 Point Harnesses // Profi II ASM // HMS Motorsport
+1, better safe than sorry.

The difference between the Schroth Profi-II ASM and non-ASM belts is the construction of the inboard shoulder belt. If you add a 5th or 6th point to a Profi-II 4pt ASM, you have to switch out that belt with a Profi-II non-ASM shoulder belt to make it compatible with the HANS.
 

·
Registered
Joined
·
664 Posts
Sounds likle the reason the belts are slipping off is due to the seat. I have never measured the distance between the harness holes in the stock seats, but I would guess that it is more than 3 inches. The seat is probably pulling the straps off the HANS by spreading them too far apart. I went with an aftermarket seat that has a center shoulder harness cutout. My HANS feels extremely secure. Make sure you follow the instructions from HANS. They are simple since they use inches/cm instead of angles. Also, as others have mentioned, ASM and HANS may not be safe.
 

·
Registered
Joined
·
1,032 Posts

·
Registered
Joined
·
5,094 Posts
Fishguy, at least I was able to tighten the strap directly on my shoulder while on the back straight.
there is no way that I could tighten my harness down as tight as it needs to be while driving the car on the track at the same time.
really the only way i get mine as snug as i like is to have someone other than myself crank down the belts for me. i get them so they are as tight as i can stand, then wiggle in the car a bit, exhale, and then get then cinched down again.
as tight as they feel in the pit area, I dont even notice it while on track.
another trick i was taught to really tighten the belts down well is to saw the the belts side to side while they are being pulled tight. you can tighten them down more this way rather than just tugging straight down.
if you go to the track alone, then just find a buddy in another run group near you and help each other with the belts. I have never had anyone so no to my asking for help.

I am going to guess the same thing as azreason as far as your seat goes, and combined with the harness not being near as tight as it can/should be.

Aslo, just thinking out loud, how layed back is your seat in its current installation? again pictures might be very helpful for this thread to help you.

just FYI, my rear view mirror in my 944 is adjusted for when i am strapped into the car and tightened up. my perspective is about 2 inches lower (or more)when i am strapped in with the harness tight as opposed to just sitting in the car w/o anything holding me in, its that tight.
 

·
Registered
Joined
·
116 Posts
Discussion Starter · #18 ·
Yes good chance I am not strapped as tightly as I could since it is the left belt that slid off twice probably under fast shifts to 3rd and 5th, too much right shoulder play.

So got a chance to get in the car and look at things today.

Angle is fine.

But the slots in the OEM seat are ~7.5", that seems too wide no? Having a hard time deciphering the math for that on the Schroth document.
 

·
Registered
Joined
·
9,786 Posts
Yes good chance I am not strapped as tightly as I could since it is the left belt that slid off twice probably under fast shifts to 3rd and 5th, too much right shoulder play.

So got a chance to get in the car and look at things today.

Angle is fine.

But the slots in the OEM seat are ~7.5", that seems too wide no? Having a hard time deciphering the math for that on the Schroth document.
At least in my case the slots in the stock seats are ~6.5" apart, but distance between the belt guides (separated by the vertical support) on my HANS is 7"... so even if the seat slots were closer, the belts really can't be any closer than the width of the vertical support on the HANS as they pass through the seat back.

In the Lotus with a harness bar, there's really no way that the bar is going to be more than 8" from the back of the seat, so according to Schroth you don't need to cross the shoulder straps. You may want to use rollbar padding (tie-wrapped in place) to restrain the shoulder belts from moving laterally on the bar.
 

·
Registered
Joined
·
5,094 Posts
You may want to use rollbar padding (tie-wrapped in place) to restrain the shoulder belts from moving laterally on the bar.
use a steel collar that is clamped in place on the harness bar on the outside of the harness to keep it from seperating while on the harness bar, or better, use 4 collars, 1 on each side of the harness where it mounts to the harness bar for each shoulder strap.
IMO, roll bar padding is to soft, and can be potentially moved.

please post a picture of you in the seat, and you in the seat strapped in with the harness and the helmet/HANS on. we might be able to help see something that you dont since your the one in the car.
I have learned a lot from looking at pictures of myself belted into my car.

I do think that each application for HANS compatibilty is per the user, so your body size may effect the usability of some seats.
sparco makes many seats of various sizes; for big guys(circuit pro for example) or little guys(circuit for example).
I know nothing about the hans seat in the exige S other than it says HANS on the seat , right?
post up a photo if you can get one.
we are here to help.
I will say that i saw a wreck this year that the HANS saved the drivers life, no doubt about it.
The impact was so hard that when the car hit a wall it actually sheared the (harness) bar that the harness mounted to completely out of the car.............. thats a huge g load on ones neck. might be worth using AN bolts where the harness bars mount to the lotus.
this is just another reason why i wont get in a car on the track w/o my H+N restraint.
 
1 - 20 of 29 Posts
Top