Thick Air??

[placidfemme]

This might seem like a random kinda question...

I've noticed that some days there is no wind at all... Look outside and not a leaf is moving on the trees... pretty much a perfect day for riding... but then once your on the road it feels like the wind is blowing... I'm not sure how to explain it but it feels like thick air.

An example... heading up over the harbour bridge... the flags arn't even moving but it feels like I'm riding head on into the wind...

Why is that?

[MSTRS]

You put on weight overnight??

[Slingshot]

Because you're moving relative to the air.

Riding through still air at 50ks would feel the same as sitting still on the bike in 50k wind.

[Beemer]

When there is no wind, YOU are still travelling at speed and therefore creating resistance - therefore you feel like you are heading into a head wind. It's something to do with the displacement of air when something moves through it.

When I first rode at 100kph I said to someone "boy, isn't it windy!" and was told "no, that's what it's like when you're riding a bike!"

When it is warmer the air is less dense so you move through it easier - if it is damp or cool, the air is 'heavier' if that makes sense!

[Sniper]

Theory or relativity

[placidfemme]

Um... ok let me re-word that...

I know what it feels like to have "normal" air pressure against you because your moving (so obviously there is wind pressure). But I'm talking more than "normal" air pressure... it feels like your riding against the wind, so there is extra force against your body/bike (maybe a better way to explain it... going 50km with no wind but the pressure on you feels like your either (a) riding head on into wind or (b) riding at say... 90km

*wishes I had put on weight*

[bugjuice]

take into account air being blown off from other vehicles, especially trucks and buses.. I know what you mean tho

[John]

I invented gravity.... :\ seriously... no... I mean it .... man am I random or what.

But seriously, what I hate is how bikes get whored by wind, driving through town people must think I'm crazy... swirving all over the place when there is a gap in the buildings, its even more fun at 100kmph+ yup you seem to get alot further across the road when you get a gust, but again irelavent fuck I need a coffee.

[hondacmx450]

it is funny how you talk about 50 kph what happen to 200kph mmmm what then year if you dont like the wind bye a car luv ya

[placidfemme]

it is funny how you talk about 50 kph what happen to 200kph mmmm what then year if you dont like the wind bye a car luv ya

Was I complaing...?? I'll buy a car when you learn to read :weird:

The 50km was an example... did you happen to miss that?

[John]

Was I complaing...?? I'll buy a car when you learn to read :weird:

The 50km was an example... did you happen to miss that?
we are all high, share love - love the children god is the answer but satan is the truth

[placidfemme]

we are all high, share love - love the children god is the answer but satan is the truth

lol John you should share some of what you've been taking... *could need some of that today at work*

[hondacmx450]

Was I complaing...?? I'll buy a car when you learn to read :weird:

The 50km was an example... did you happen to miss that?
oh you get so mad so easy calm down and here have a ice cream you better now good
you find at 50 kph the wind going over the top of your bike is going faster than the air going under your bike more to think about

[John]

oh you get so mad so easy calm down and here have a ice cream you better now good
you find at 50 kph the wind going over the top of your bike is going faster than the air going under your bike more to think about
hey I want a fucken ice cream motherfucker... please?

[Motu]

I remember the first time I did 100mph,the old magic ''ton''....with no helmet or goggles my eyes were streaming,and when I took my left hand off the Lightnings bar to wipe my eyes - my arm was ripped off and ended up flapping uselessly behind me! Bloody hell! I didn't know that would happen,and it was a real effort to get it back on the left grip where it belonged.

One of the best feelings riding a bike is riding in a tailwind,just wafting along in still air,pure magic....until you turn around and ride back into it...

[placidfemme]

oh you get so mad so easy calm down and here have a ice cream you better now good
you find at 50 kph the wind going over the top of your bike is going faster than the air going under your bike more to think about

Is it Rum & Rasin icecream? My mom said never to accept "gifts" from strangers... and your stranger than most... p/t

But seriously... I think I've explained it wrong...

*hardly ever rides at 50km*

It's not the normal air force you feel when riding... it doesn't matter whether your going 20km/ph or 240km/ph.

It's actually weirder (is that a word?) to ride in the "thick air" then it is to ride in the wind... it feels totally different (and different to the normal pressure caused by riding at different speeds too).

I've tried explaining it... but obviously I'm not wording it right lol...

Oh well...

[Lou Girardin]

I struck some "thick air" last night.
Musta been the broccoli.

[scumdog]

Um... ok let me re-word that...

I know what it feels like to have "normal" air pressure against you because your moving (so obviously there is wind pressure). But I'm talking more than "normal" air pressure... it feels like your riding against the wind, so there is extra force against your body/bike (maybe a better way to explain it... going 50km with no wind but the pressure on you feels like your either (a) riding head on into wind or (b) riding at say... 90km

*wishes I had put on weight*

Can't be naffed reading the whole thread but at the risk somebody has already said this:

It only takes a minute amount of head or tail wind to make a hell a lot of difference to the amount of 'wind pressure' you feel. Physics boys might be able to explain it better.

Next time you are riding into a mild head wind take the time to turn around and ride the other way for a km or so, you'll be amazed how much difference that little breeze makes.

[sels1]

When it is warmer the air is less dense so you move through it easier - if it is damp or cool, the air is 'heavier' if that makes sense!

Yes it does! Temperature and humidity come into it. Cool air with a high moisture content feels 'thicker' ie when it is near dewpoint and close to turning into fog. Even when fairly dry, cool air can be percieved as thicker....something to do with the our bodies sense it

[placidfemme]

Yes it does! Temperature and humidity come into it. Cool air with a high moisture content feels 'thicker' ie when it is near dewpoint and close to turning into fog. Even when fairly dry, cool air can be percieved as thicker....something to do with the our bodies sense it

Sweet thats the kind of answer I was looking for...

*knew I wasn't crazy... well not completely anyway*

[Velox]

It only takes a minute amount of head or tail wind to make a hell a lot of difference to the amount of 'wind pressure' you feel. Physics boys might be able to explain it better.

Next time you are riding into a mild head wind take the time to turn around and ride the other way for a km or so, you'll be amazed how much difference that little breeze makes.
Yeah - I second that. Even when it seems really still, if there's just a slight movement of the air towards you, it can make quite a diff in what you feel when you're on the bike. Really, really ocassionally it feels like I'm really battling the air and I get a sore neck and then when I stop there's pretty much no wind at all! That's what you're on about eh PF? It's amplified for me by the fact that my bike has no fairings - make a huge difference.

[placidfemme]

Yeah - I second that. Even when it seems really still, if there's just a slight movement of the air towards you, it can make quite a diff in what you feel when you're on the bike. Really, really ocassionally it feels like I'm really battling the air and I get a sore neck and then when I stop there's pretty much no wind at all! That's what you're on about eh PF? It's amplified for me by the fact that my bike has no fairings - make a huge difference.

Yeah something like that... it was just something I'd been wondering about for ages... no wind but a lot of pressure... I couldn't figure it out so I thought I'd ask... :)

[Storm]

It's amplified for me by the fact that my bike has no fairings - make a huge difference.

From what I hear you need something to slow you down. Stops you from showing up all the bigger bikes :bleh:

[Velox]

From what I hear you need something to slow you down. Stops you from showing up all the bigger bikes :bleh:
:bleh: The old Jade's not exactly a "top-end" bike! It can do around 180ish (says it can do more but I dunno about that). Just loves the revs!
Fairings must be so useful though eh - firstly for counteracting "Thick-Air"Copyright PlacidFemme 2005 but also for keeping dry. But then again, I guess with a naked bike - your more "out in the elements" which is cool. Sometimes.

[Eurygnomes]

I can't wait to get a bike with fairing. I don't care if it makes me look 'uncool' to NOT be out in the elements at all times, I hate having a sore neck/back/shoulders from riding into the wind (and tensing up...yes, I'm TRYING to relax...but the waterfront gusts and crosswinds in Ngauranga gorge, and and and aren't exactly relaxing on the lightest unfaired bike on the planet!).

I'll take the faired heavy bike please...oh...and a bit more power wouldn't go amiss sometimes. I turn into a headwind and it knocks about 10k off my speed in a very short period of time. Probably couldn't STOP as fast as it decelerates! :thud: (joke, I could, if I wanted to use the breaks...I'm just being facetious!)

[Ixion]

Our impression of "wind" is really an impression of gustiness. It is possble to be in a mass of air which is moving but not at all gusty. In such a case you will not readily register conditions as being "windy", because there is no variation in the wind pressure. We only notice "windy" when the air speed/pressure changes.

If such a constant pressure is coming from behind,we just register that the bike going really well today (and bore everybody with the top speed figure we claim at the pub tomorrow). If from in front , we feel it is "struggling" , and worry about the engine packing up. If from the side we may (if we pay attention) notice that we are riding with a slight constant lean.

[Ixion]

I can't wait to get a bike with fairing. I don't care if it makes me look 'uncool' to NOT be out in the elements at all times, I hate having a sore neck/back/shoulders from riding into the wind (and tensing up...yes, I'm TRYING to relax...but the waterfront gusts and crosswinds in Ngauranga gorge, and and and aren't exactly relaxing on the lightest unfaired bike on the planet!).

I'll take the faired heavy bike please...oh...and a bit more power wouldn't go amiss sometimes. I turn into a headwind and it knocks about 10k off my speed in a very short period of time. Probably couldn't STOP as fast as it decelerates! :thud: (joke, I could, if I wanted to use the breaks...I'm just being facetious!)


Actually, a faired bike may give you bigger aches in shoulders and back than a naked one.

If you have your riding position correctly set on a naked bike, you will be "sitting on the wind" at your cruising speed. The wind force will nicely balance out your weight so there is no load on your arms, and no need for your back and shoulder muscles to hold your upper body up. You are literally being held up by the wind.

With a faired bike, your upper body weight comes on your arms. No wind pressure to hold you up. If those (arms) are to be held relaxed (as they should) you must support your body weight with your shoulders and back. causing aches. BMW discovered this with their early faired bikes and more or less invented their own "sit up an beg" riding position, to take the load off the riders arms.

[GNR]

Yes it does! Temperature and humidity come into it. Cool air with a high moisture content feels 'thicker' ie when it is near dewpoint and close to turning into fog. Even when fairly dry, cool air can be percieved as thicker....something to do with the our bodies sense it

Its because cool air is "thicker" than warm air, as warm air expands.

cool air can hold less mositure than warm air as well,

[sels1]

Interesting avatar you have there mate,
:

Why yes, its a Munro IM146 Mk IV generator anemometer with syncronous magslip windvane and was used by Meteorological Services worldwide until the advent of electronic systems. Still a lot in use. Installing/calibrating/maintaining them is one of my tasks at work.

[sels1]

An I'd bet you know about inversions and catabatics as well aye. :niceone:

yes, "I've done a course in that " :lol: