04-15-2008
|
|
red mist junkie
Winning Races / Advanced Member (250+ Posts)
|
|
Join Date: Jun 2005
Location: JOHNSTOWN, NY
Age: 68
Posts: 436
|
|
HELMET LIFT
I am looking for suggestions. At higher speeds my helmet feels as though it is pulling off my head. It is a Simpson Diamondback. At higher speeds(over 100 mph) the helmet lifts so much that it affects my vision.
This helmet seems to have a rather protruding chin area that does not have any covering between my chin and the front of the helmet.
If anyone else has this kind of problem and has come up with a solution i would love to hear from them.
__________________
" I wish I was the STIG"
|
04-15-2008
|
|
G-force junkie
Speed Through Zen / Advanced Member (2,000+ Posts)
|
|
Join Date: Nov 2006
Location: Changes weekly
Posts: 2,183
|
|
Re: HELMET LIFT
Sounds like an area of relative high pressure is building up under/inside the helmet at high speed due to the relative low pressure area caused by the air rushing over it. The Diamond back supposedly has Aerodynamic Countermeasures designed into it, but obviously these are not working at least for this particular problem. The key is likely the open area between your chin and the helmet which is allowing relatively high pressure air to build up inside the helmet. This is a design flaw. You need to fill this in with padding, preferably inserts designed for it to fit the space in comfort, allow you to remove the helmet, and to be fireproof. I wonder if those dust skirts that hang down would do the trick? (I think I've seen Rob Slonaker with a helmet like that.) If this doesn't solve the problem, to avoid having to buy a new helmet you can investigate adding a flange or ridge to the top of the helmet somehow to break up the airflow (take a look at some of the helmets that have this) but just jury-rigging it without wind tunnel data might cause other stability problems. Otherwise I'm afraid you'll have to buy a better designed helmet, such as an Arai or a Bell Vortex. I'm not familiar with Simpson helmets and how well they work for open cockpit cars, but if you want to stick with them the Shark looks superficially like it might be ok but you'd have to test it to be sure.
__________________
"All things are ready if our minds be so." -- Henry V
|
04-15-2008
|
|
Podium Regular / Advanced Member (50+ Posts)
|
|
Join Date: Feb 2005
Location: miami beach
Posts: 68
|
|
Re: HELMET LIFT
I had a Simpson Voyager which was originally purchased for DE's and Sports cars and had the same issue at high speeds in an open car. I ended up getting a new helmet designed for open wheel and the differences were dramatic. There are some products that you can purchase after market that will probably help as Harsha suggested like helmet spoilers etc.
|
04-15-2008
|
|
Hey Wait For Me
Podium Regular / Advanced Member (50+ Posts)
|
|
Join Date: Apr 2007
Location: Durham, NC
Posts: 69
|
|
Re: HELMET LIFT
I don't know the Simpson line super well since I don't carry it. So I went and looked at the diamondback. It looks like it may be a helmet geared towards drag racing and not so much open-wheel road racing. That may be part of the issue. Simpson does have strong roots in the drag racing world so it wouldn't shock me.
As for Simpson helmets that I know people have used with good success are the Shark and the Speedway VUDO. The previous owner of my car has the Shark and he switches between that helmet and an ARAI.
There are some aero bits you can buy for helemts like Harsha mentions. I haven't used any, nor has anyone I know.
I had an M2 Pro when I first started racing open wheel and if I didn't have it strapped on I can only assume it would have lifted right off my head at the end of the straights at Road America. I've used a Bell GTX with good success and I just picked up a T-6 Interceptor for on-hand stock that just happens to be the right size for me too. It will cut 5 seconds from my bench racing laps. I might accidentally send it to the painter to make it all pretty too.
|
04-16-2008
|
|
Testing Mid-Corner Speed / Advanced Member (500+ Posts)
|
|
Join Date: Nov 2006
Location: Louisville, KY
Age: 70
Posts: 829
|
|
Re: HELMET LIFT
I use a Simpson Super Voyager or a Bell M3 for Skippy stuff and a couple of Suomy's or the same Simpson on the motorcycle, which occasionally (wink) sees higher straight line speeds than the Skippy RT's. The Simpson and Bell are both cue-balls, smooth tops with no aero devices, while the Suomy's have alleged aero 'stuff' on top. I can't say that any of them have less lift over 80-90 mph than any other.
__________________
Laissez les bons temps rouler!
|
04-17-2008
|
|
Testing Mid-Corner Speed / Advanced Member (500+ Posts)
|
|
Join Date: Aug 2004
Location: Upstate NY
Posts: 985
|
|
Re: HELMET LIFT
Keep your speed under 100MPh!
|
04-17-2008
|
|
Testing Mid-Corner Speed / Advanced Member (500+ Posts)
|
|
Join Date: Nov 2006
Location: Louisville, KY
Age: 70
Posts: 829
|
|
Re: HELMET LIFT
Quote:
Originally Posted by LimeRockRacer
Keep your speed under 100MPh!
|
"Now don't be a pain in the ass, Erich."
__________________
Laissez les bons temps rouler!
|
04-17-2008
|
|
red mist junkie
Winning Races / Advanced Member (250+ Posts)
|
|
Join Date: Jun 2005
Location: JOHNSTOWN, NY
Age: 68
Posts: 436
|
|
Re: HELMET LIFT
I guess I'll just have to make my car W I D E R to keep you guys behind me.
On a serious note; I called Simpson and they are sending me a chin flap to eliminate the high pressure area under the chin.
So I may be able to drive fast after all HA HA HA HA
__________________
" I wish I was the STIG"
|
04-18-2008
|
|
Grand Master
Carbon Fiber Keyboard (3,000+ Posts)
|
|
Join Date: Aug 2004
Location: location, location
Posts: 5,399
|
|
Re: HELMET LIFT
Here's a short thread that touched on this issue recently if you don't mind wading through some nonsense. http://www.teamjuicyracing.com/forums/show.php?t=2665
If the buffeting your experiencing is in a Skippy car it might be due to a seating position so far forward that it puts you heavily into the slipstream. Those little Plexiglass windscreens actually do make a difference and if you position your body and helmet far enough forward you'll get more than your share of buffeting.
The chin flap will probably help the situation, but anything to move yourself rearward will also probably help yourself as long as you can still reach the pedals and steering wheel.
Good luck!
__________________
You draw 'em a picture and they eat the crayons... (Duck Waddle commenting on the creative ways some people interpret driving instruction.)
|
Thread Tools |
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is On
|
|
|
All times are GMT -4. The time now is 04:43 AM.
|