znomit

Thanks, thats an interesting read.

Sy Reene

FIFY

Older thread on MIPs, someone said helmets with MIPS come with instructions to not wear a cap/liner underneath. As I always wear one (in summer for UV protection; in winter for warmth), MIPS is a non-starter for me. YMMV

DiabloScott

I always wear either a cycling cap or a HeadSweats under my helmet too.

I have looked at a lot of MIPS helmet manufacturer sites and I don't see this warning anywhere. Not in the helmet sites, not on the MIPS technology site; which I think it would be if it were an issue. It's absolutely NOT in the Giro MIPS manual that came with my new helmet.

I've heard this rumor as well, and seen it posted in here somewhere (quite often from you), but never anything official.

I even found the original thread I think you're referring to: Best ventilated helmets

It references the BELL helmet manual and a consumer support e-mail response, but the liner warning is not in the current version of the BELL helmet site either: https://www.bellhelmets.com/bellspor...l_B5000433.pdf


So maybe it used to be in there. Maybe some customer service monkey confirmed that. But if it were important it would be highlighted, so I'm going to call BS unless shown otherwise.

**Not making any statement on the concussion prevention ability of MIPS, just that wearing a HeadSweats shouldn't factor into your decision.

Cuyuna

The force necessary to crush the styrofoam in your helmet is force that isn't applied to your skull and the brain inside it. Relative to skull fractures...by spreading out the area of impact it results in less focally applied force therefore some degree of lower risk of skull fracture. Helmets are potentially beneficial.

Sy Reene

I have referred to this old thread a few times. I kinda saw that thread as an easily-buried and overlooked, but a fairly important one.. if all that was said in that thread is in fact true.

I've seen the bell manuals online.. and I don't think I could find their sister company's giro helmet instructions online. Please note however.. that while there is no helmet liner or hat warning, there's also NO mention of the word "MIPS" anywhere in this online "Owners Manual".

I guess if I was in the market right now for a new helmet, and thought I wanted a MIPs helmet, I would redo a direct query to a couple helmet makers to ask the question about safety of wearing clothing articles underneath these.

Kontact

The force initially applied to your noggin will be whatever amount of force it takes to exceed the yield strength of the styrofoam - which is somewhat hard stuff. So your head is going to be met with at least that much force before the styrofoam's structure collapses and the foam begins decelerating your head. Up to that point the helmet is going to feel like it is made of pine.

That is a sort of lower window to minor injury or concussion, even though the helmet is able to absorb a much greater impact by destroying itself.

DiabloScott

The BELL manual for Aus/NZ says not to wear anything under your helmet - any helmet, no mention of MIPS. How does that affect your decision?
https://www.bellhelmets.com/bellspor...01076300-C.pdf



So we agree. There are no current helmet manufacturers, as far as either of us know, who print in their user manuals, that caps or doo-rags should not be worn under a MIPS helmet. And the MIPS corporation themselves also make no such warning. And nobody should be claiming otherwise.

Sy Reene

The AUS manual tells me that Bell hasn't got their ***** together if they can't publish consistent reading material for worldwide applicability and consumption, and makes me wonder who at Bell really knows what.

As to your reference of "print" manuals, I have absolutely no idea. I wouldn't outright claim @howheels is lying though (who was referring to the printed instructions that came with his helmet). So far, in this thread, we're all quoting online (not print) genericized manuals.

I'm also not sure there'd be any benefit to the MIPs company(?) publishing anything that doesn't concern them directly.. they're licensing to helmet companies, not selling directly to consumers. What they might tell the licensing companies that use their tech could be different than what choose to present in their own online public-access material.

JohnJ80

Wearing a cycling hat or do-rag under a MIPS helmet should have no effect. The slip plane of the MIPS technology would not be impacted by anything under it as long as it doesn't between the parts that are designed to slip.

J.

Kontact

You would hope that thin fabric would have little more effect than the hair many of us have up there.

Cuyuna

Peak deceleration that the skull/brain are exposed to is decreased by the total amount of energy it takes to crush the styrofoam. The yield strength of the Styrofoam in the helmet liner is tested and designed around that deceleration.

Sy Reene

I'm guessing that if there's an issue with a beanie/liner, it's not the cushioning of the material, but it's proclivity to slide or move around on the head.

Kontact

Exactly - peak deceleration. The helmet is designed to for a significant impact, not more minor ones. Those are going to hurt.

DiabloScott

Except that THERE IS NO ISSUE.

1. The current Giro owner's manual says nothing about this (not on-line but I have a hard copy).
2. The current Bell owner's manual says nothing about this.
3. The current Bell owner's manual for NZ/AUS says not to wear anything under ANY helmet - whatever this is it's not a MIPS warning.

4. The 2016 Bell owner's manual apparently said something either about MIPS or any helmet.
5. The Consumer Support e-mail to user @howheels appears to have been written by a marketing person who copied some blurb and made an unsupported conclusion.



And in my experience, the Headsweat keeps my helmet more securely in place, it slides around more when I don't wear the Headsweat.

79pmooney

Actually, warning #5 is serious. If it is followed faithfully, it protect the user from concussions and more serious injury almost always. Think about it. In most of the western world, if you wear nothing under your helmet, you will be escorted to a place where you can do little harm to yourself.

The key words are "under your helmet". So, no jersey, no shoes, no shorts. The odds are very good the police will show up before an ambulance is needed!

Ben

Racing Dan

Right, thats exactly what they meant :-)

Or maybe its just layer talk, to prevent liability, in case people decide to wear hair clips, hats with metal bits or any other untested headgear. Maybe.

Sy Reene

I like the definitive all caps boldface, followed by your points 3, 4, and 5 which point to possibility that there could be an issue, though interestingly might apply to potentially all types of helmets. #5 is hinting at possibility that you're able to read minds.

Kontact

I'd like to know if Bell has a recommended maximum amount of hair that will cause the helmet to malfunction as if you were wearing something, if they are serious about this limitation on the design.

Racing Dan

In online squabbling, telepathy is generally accepted as valid arguments. Didn't you know? :-)

Sy Reene

I doubt it.. but I don't think it's too hard to imagine that yes, a person having a lot of hair will have a helmet fit differently (and probably somewhat less safely) than someone with less hair.

Kontact

This demonstrates why the warnings offered are about litigation and not safe operation. If Bell was concerned with safe operation, they would quantitize the amount of acceptable loose fiber (hair or not) that can intrude between the helmet and bare skull. Physics doesn't change because your thick, wavy hair isn't made of cotton.


Given that, consumers have to choose how they want to deal with such warnings, including whether they will benefit from MUPs if they have thick hair, and whether Bell's silence on hair actually means that the helmet won't work because you had a thin do-rag on. And if they don't work in a crash because of your do-rag, if you are actually going to care that this might limit your ability to sue Bell for damages.

DiabloScott

Whatever USED to be in the Bell manual, was removed for the current manual; that indicates a retraction.

This whole thing smells of urban legend... along the lines of eating PopRocks and drinking a Coke.

RGMN

Most helmets in the US (at least the ones legally sold must meet CPSC or ASTM) are designed to impart less than 300 g for a 13.9 MPH (6.2 m/s) impact. European helmets are designed to impart less than 250 g for a 12.1 (5.4 m/s) impact. Whether a crash at 13.9 or 12.1 mph is significant is left up the reader.

A good source for bike helmet information is helmets.org. They even have a picture of a helmet designed to prevent concussions.

Sy Reene

I decided to do what that original OP did and sent a query off to a couple places (Bell, Giro, Lazer and MIPS). The only response I've received back, is the following nicely put letter from Bell. IOW, technically, everybody is right

The question: "I have a product question related to your cycling helmets. Can you advise if either MIPs and/or Non-MIPS helmets are safe to use with a helmet liner/cap underneath (eg. headsweats, skull cap, cycling cap, balaclava, etc.)? The literature is unclear on this."

The response:
"This is a great question. Technically, we have to advise against this, as all heads are different, and there are an infinite variety of caps, balaclavas, etc. one can wear under a helmet. However, if the helmet is snug and properly adjusted per the owners’ manual, and the cap is thin (a cycling cap, skull cap, etc., not a thick wool winter hat), we have never seen an issue in our retention testing. There is no research on this issue, perhaps because of the huge variety of caps available.

Certainly any cap will raise the helmet up and reduce the covered area of the head. Thicker caps would raise the helmet substantially more, and in some accidents this could present a serious risk.

I can tell you also that many of us here wear cycling caps or thin skull caps under the helmet, in particular in the winter.

Thanks.
Thom Parks
Senior Director of Product Safety
Bell Sports, Inc."

wphamilton

Serious question: have you (anyone) ever refrained from wearing a cap under your helmet because you thought it would be less safe?