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Topic: Why full face helmets are daft. (Read 6200 times)
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grahamt1980
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Maybe Leatts and the like will bring about changes in helmet design as they become more popular?
I highly doubt that to be honest. Unless the Leatt comes down in price by ~£200 they won't do well. Overpriced b*lls**t if you ask me. Are you honestly being serious? Doesn't even warrant a response really. I don't know if there's been a big increase in MX/DH neck and back injuries, but it's more the case that the technology to help prevent such injuries has only recently been introduced on to the mass market. Seems perfectly logical that with the speeds and track difficulty increasing in our sport that the protection should improve in accordance with it. Rootes It is to exspensive though! I made the mistake of saying this to a mate of mine. He is currently in sheffield northern general in the spinal unit after paralyzing himself from the waist down. Ok so it wasn't a neck injury but try using the expense argument if you know it could keep you out of a wheel chair. Richard just looked at me and i realised what i had said. Yeah sure its expensive but its your life when it comes down to it |
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Bruises fade, chicks dig scars, but deraileurs are friggin expensive
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Dangerous Dave
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SDH Rocks!
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Wow, talk about the thread that won't die! Dangerous Dave (trying to think who you are), I didn't mean to rip on single pivot bikes. My point is that there is nothing wrong with the single pivot design. They work perfectly well! But that didn't stop people from thinking outside of the box and coming up with linkage designs. Just like there's nothing wrong with the current crop of helmets (at least for most people), but that shouldn't stop us from thinking outside the box. My bikes a Balfa 2-step by the way...it defies classification.  Parallel link 4-bar perhaps. Or "pre cursor to DW link". Hehe, it's Alex's mate, the one with the Cannondale Judge. I knew you were really into engineering, but I thought it was only from an actual bike point of view, had no idea you had such broad scopes. Tbh I like it. What you say about our helmets being borrowed from MX is pretty spot on. But, then to be fair so many of our equipment and tricks are borrowed from MX/BMX! Would be nice to see if we really can make a helmet that is totally purpose built for DH racing. Though as I said, I doubt it's unlikely it will appeal to joe blogs public. I suspect MTB isn't ready for radical changes! Sorry I misunderstood your single pivot post - just re-read mine and it may have come across a touch ott defensive - sorry 'bout that dude. |
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sketchmasterx
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I made the mistake of saying this to a mate of mine. He is currently in sheffield northern general in the spinal unit after paralyzing himself from the waist down. Ok so it wasn't a neck injury but try using the expense argument if you know it could keep you out of a wheel chair.
Richard just looked at me and i realised what i had said. Yeah sure its expensive but its your life when it comes down to it
I know what you mean and im really sorry about your mate that really sucks and don't get me wrong I'm all for safety kit had i not had a helmet on when a car hit me last month i don't think i would be typing now. The problem is though there are hundreds of ways we could make ourselves safer in every aspect of life but at the end of the day it comes down to money, for example some newer cars have higher safety standards, soldier with better armour etc etc. (Maybe a leatt brace for my commute in case the car hits me again?). I could probably push myself and go and buy a neck brace if i wanted but there are people out there who just don't have that kind of cash especially as there allready trying to take part in a expensive sport and sods law is that it's those people who will get hurt not the idiot with all the cash and bling who weaves down a main road with out a helmet on. Also they will come down in price over time but how quickly, they should lower there margins (if they can) and get them out there! |
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Dangerous Dave
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SDH Rocks!
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Would be nice to see if we really can make a helmet that is totally purpose built for DH racing. Though as I said, I doubt it's unlikely it will appeal to joe blogs public. I suspect MTB isn't ready for radical changes!
Aren't all of us (apart from those with MX lids) already wearing lids purpose built for dh? I'm sure if there was a lot of room for improvement, it would probably already be made; but the fact is, at the moment: they look pretty good and they protect your noggin', and only a small percentage of people experience this airflow problem (although I imagine it may well be in their heads). Purpose as in adapted, yeah. You're probably right - the airflow "problem" may not affect us all, may not be a big issue - but - where is the harm in doing research? Or innovating a product that may improve current designs? When I say purpose built for DH racing, i meant DH Racing, not just "larking about" DH. Ie, as Pslide says, aerodynamic as poss, and not fatiguing the rider in any way. You might knock this kind of scientific approach - but it's been proven in the past that a scientific approach to Dh racing works, and I don't need to tell ya who did that. Hell, the research (if it ever went ahead!) may show this all a load of complete conjecture and it really makes no odds at all! Surely though, this sort of thinking has been at the heart of some of the best ideas? "Hmm, wonder if this would work better, lets give it a go and see".  |
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Harry Barn-Owl
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Let it all hang out.
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Would be nice to see if we really can make a helmet that is totally purpose built for DH racing. Though as I said, I doubt it's unlikely it will appeal to joe blogs public. I suspect MTB isn't ready for radical changes!
Aren't all of us (apart from those with MX lids) already wearing lids purpose built for dh? I'm sure if there was a lot of room for improvement, it would probably already be made; but the fact is, at the moment: they look pretty good and they protect your noggin', and only a small percentage of people experience this airflow problem (although I imagine it may well be in their heads). Purpose as in adapted, yeah. You're probably right - the airflow "problem" may not affect us all, may not be a big issue - but - where is the harm in doing research? Or innovating a product that may improve current designs? When I say purpose built for DH racing, i meant DH Racing, not just "larking about" DH. Ie, as Pslide says, aerodynamic as poss, and not fatiguing the rider in any way. You might knock this kind of scientific approach - but it's been proven in the past that a scientific approach to Dh racing works, and I don't need to tell ya who did that. Hell, the research (if it ever went ahead!) may show this all a load of complete conjecture and it really makes no odds at all! Surely though, this sort of thinking has been at the heart of some of the best ideas? "Hmm, wonder if this would work better, lets give it a go and see". Ah I get where you're coming from. No you're right, it's the right attitude to have, didn't mean to knock it. I suppose I'm being a tad narrow minded, as I'm pretty happy with my lids as they are!  |
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ShockerAll the gear and positively no idea.
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cookeaa
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Apologies for the Nova comment then…
I’ll try and be more constructive…
Assuming then for a moment the re-breathing issue does exist, from a CFD (my knowledge here is also limited) point of view I don’t reckon your extra Chin guard holes are the most graceful solution though…
Surely the problem isn’t so much to do with air intake at the front of the helmet as it is, exhaled air exhaust…
Most peoples riding position has their head angled a touch down at the front, meaning air should be flowing in over the top of the chin guard and outwards at the underside of the chin guard, the major restriction therefore is the rider, whose lower face, neck and upper chest are all restricting the exhaust path for the frontal area of the helmet, current designs generally have a larger cross sectional area for intake than Exhaust (many taper towards the bottom opening, your big inlet duct will compromise protection but more critically they are simply an increase in inlet area does not really address the problem you have identified which is poor exhaled air exhaust…
You need to find a better route for exhaled air to leave the forward area of the helmet…
I’m sure a proper model could bear this out, a lot of people who seem to have found the same issue are complaining it happens with 661’s and other helmets that have a closer chin guard and therefore a more restricted exhaust path…
It may seem counter intuitive at first but larger section, lateral (towards the sides; probably slightly in front of and bellow the riders ears) and/or internal ducting to direct air flow from the mouth area, around the riders head and neck to the rear or sides of the helmet would make more sense to me, you want that air gone ASAP and the prevalent airflow is directed front to back…
Aerodynamically I reckon you may be right, modern lids are not so sleek at they could be and it’s fair to say they present a fair amount of draggy surfaces, However seeing as many riders would have to be forced into skin suits (which do make a difference) fully aerodynamic helmets would have to be some way off…
To be honest I my last 2 helmets have been MX lids and while I valued the added protection, they are too hot and too heavy, current MTB full facers do address this, they may look similar and have similar origins to MX lids but they are very much designed around the application of DH racing and are not simply cut down MX lids…
Also the best method I’ve found to improve comfort is a grade 2-3 shearing every 4-6 weeks, you’d be amazed the difference buzzing your thatch off can make to the temperature inside your helmet….
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Pslide
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Velocitus Maximus!
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Ha ha...yeah, I usually have a #3 clipper around the sides and back...
I must admit, you've taken this a step farther than I did, and you make some very good valid points I hadn't even really thought of. Exhaled air IS probably the more critical air flow problem. I like your ideas for the area around lower cheek bone and below the ear...makes sense that that is the best exit option, although often the cheek is used to stabilize the helmet, so it would have to be clever engineering.
After considering your comments, my Nova design isn't probably the best (OK, you're right!). The air intake vents should be angle a bit more upwards considering the head position during riding. This would also reduce dirt ingress in a crash, so accomplishes two things. However, you'd really have to do a model to understand not only how the air goes in, but how it best exits as you've pointed out.
You may have just inspired me to revisit this with a more analytical approach...
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cookeaa
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Glad to have been of some assistance…
Going a step further still, perhaps before embarking on the actual design a reference study is required; gather up a few current helmets (probably best to go for the more common jobbies, strike, Remedy, D2, etc) and a couple of reference riders and try to measure each helmets effectiveness in given situations; eg: CO2 and air temp’ levels at riders mouth area relative to Ambient temp’ and CO2 levels, heart rate and headwind, temperature at key points inside the helmet, it would probably make sense to create a test rig to determine these things, it may sound crude but a turbo trainer with a big fan in front would allow you to repeat the same conditions to a rider pedalling flat out down a trail, over and over again,
It would also make sense to try wind tunnel testing if you can as well as some real world video analysis…
From a CFD point of view your are probably going to need a few “reference“ heads modelled to allow you to assess air flow for different sized users, anthropometrics can be a bugger, as certain cranial and facial features will grow at different rates, an adult males head is not simply a scaled up child’s head, and this will have a bearing on how well your design operates for each group of users...
Basically you need a starting point to improve on and that has to be existing products under benchmark conditions…
The scientific approach to product development is what you need if you’re looking to actually improve on currently available kit…
You have not chosen a simple task, I’ve had some small involvement in Running shoe and sports Eyewear design in the dim distant past, and coming up with workable human factor based designs for most sporting equipment can be a chuffing nightmare, you’ve chosen one hell of an application to consider the level of work is truly huge, and that before you even start to consider the protective role of the product on top of comfort…
Good luck…
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GiantBikes123
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isn't the visor meant to take the first blow when you crash??
yea i think so, i crashed recently and ruined ma peak, but if it hadnt had a peak on, it would have ruined ma helmet, and me in the process  ahhhhhhhhhhh thnx for tellin me |
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