If it is below 40 deg F, should I have the middle cowl open or closed

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should I have the middle cowl open or closed

  • open (adjusted away from the frame) makes rider warmer

    Votes: 0 0.0%
  • closed (adjusted closest to the frame) makes the rider warmer

    Votes: 0 0.0%
  • It doesn't do a darn thing

    Votes: 0 0.0%
  • I'd rather have pie

    Votes: 0 0.0%
  • wgara

    Votes: 0 0.0%
  • free Britney

    Votes: 0 0.0%

  • Total voters
    0
wgara = who gives a rat's ass
Ah HA!!

A rational explanation of the acronym. Thank You !!

And I thought you were having a stroke while typing - - -
Ok, that was such a civil answer, I have to fess up.

When I published the poll, it said wgira, and only after I saw the questions did I realize that I screwed up, and then I edited the poll to fix it to wgara.

and now would be another excellent time to say wgara, or even tup.

 
In the cool weather is the best time to really see where warm (hot) air is coming from. Down here in Texas the majority of the time is just hot no matter what you do!
I got an AMEN BROTHER FOR THAT! It wouldnt matter what you ride here until this week.It has been just a tad warmish.

 
So since I'm new to the bike I thought I would try a few mornings one way and then the other to see the difference. Not under 40 degrees but it was 46 when I started.

This was done with slacks (no leathers on the legs).

My first impression is that even when closed (closest to frame) some heat gets through. Especially when you get into stop and go traffic and then get going again.

When I opened them the legs were a lot warmer. From what I can tell there is more airflow. The faster you go, the more air pushes through. As it goes by the engine it warms up and due to the speed, with the cowls open you get a lot more air on your legs.

I'm sleepy so I hope that makes sense.

I also think it kept the engine a bit cooler but I'm not sure that was just getting up to speed and staying there or actual effect from the added airflow. In theory, air moving more efficiently away from the engine compartment (which would be with the cowl open) should yield cooler engine temps.

Just my thoughts and observations.

 
If you look carefully at those "doors", they do not allow any engine compartment air to escape between the open door and the frame, and onto your legs in either position. Their only purpose in the outward position is to deflect air (which is a combination of engine hot air and outside air) further away from the bike and your legs.

Some say, they are warmer in the open position because they reduce the total air blowing by on your legs.

Some say they are warmer in the closed position because you get more engine warm air on your legs.

My independent testing revealed the following:

The bike was riden with the deflectors closed on a very hot day, and my legs were hot. I then opened the deflectors and rode and my legs got even hotter. To make sure the test was valid I then closed the deflectors and rode some more and my legs got even hotter still! Confused at this point I then opened the deflectors and rode again and by now my legs were burning up to the point were I was unable to ride any further!! I stopped the bike, let it cool completely and closed the side deflectors and have never moved then since. The testing has concluded that each time you move them you will get hotter no matter which way you go!

Be carefull out there. ;)

 
The bike was riden with the deflectors closed on a very hot day, and my legs were hot. I then opened the deflectors and rode and my legs got even hotter. To make sure the test was valid I then closed the deflectors and rode some more and my legs got even hotter still! Confused at this point I then opened the deflectors and rode again and by now my legs were burning up to the point were I was unable to ride any further!! I stopped the bike, let it cool completely and closed the side deflectors and have never moved then since. The testing has concluded that each time you move them you will get hotter no matter which way you go!
that's fuckin hillarious.

 
Last time it was in the 40's I rode with one side open, and the other closed. I didn't notice much of a difference, so I switched it closed on one side, open on the other.

I think I need someone to secretly open one, and close the other. Then I should ride around with my eyes closed to decide which is better for cold weather. :unsure:

 
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wgara = who gives a rat's ass
You edited it!!!! That's cheating! If it would have originally said wgara, my web search would have found it. But it originally said wgira and that came back with nothing!

At least I voted correctly though!!!!!
Yup! Leave Britteny alone is comin on strong dood.

:jester:

 
Here's my take on the science, my opinion, and an EASY way to test on your own.

My take on the science:

I think that motorcyclists and skydivers are very keenly aware of what Wind Chill Factor is all about. If I'm in 30F air that isn't moving it doesn't feel all that cold - I could easily survive with a light jacket and light gloves. But bust out a fan and blow that same 30F air at me at 30MPH and suddenly I'll be wanting to put on a thicker layer of insulation, preferably something wind-resistant. The colder moving air pulls heat from a warmer object faster than still air does.

Along the same lines, a convection oven will heat up food way faster than a regular oven since the warmer moving air transfers heat into a cooler object faster than the still air of a standard oven does.

When the air rushes past the FJR's radiator and engine it picks up heat, and then that heated air gets directed somewhere. If you have the side vents closed (in the inward position) then air that's been heated is hitting the legs moreso than if the vents were in the open (outward) position.

I think that we all can understand the above. The point of contention is whether having the air that's been heated blowing on the shins is preferable to deflecting it away (somewhat) from the shins.

My body is supposed to be running at a constant 98.6F. However, air temps that high feel hot to me since my metabolism requires that I be able to release heat from my body at all times. So I prefer the feeling of air that's in the mid to lower 70's while at rest, or the mid to upper 70's at higher wind speeds. We're all different so your comfort range may be different from mine. Air warmer than that feels warm since it's not wicking heat from my body as quickly as I'd like. And at 99F and up the air is actually warmer than I am, so the air tries to put warmth into me - yuck! At that point I'm surviving due to the cooling effects of perspiration.

I don't know how much the air that comes off the engine heats the air. For the purposes of this discussion that would be helpful to know (anyone have a thermometer that they can strap to their leg?). But if I had to guess I'd say that when the FJR is moving the air that goes out the vents has been raised in temp somewhere between 5F and 15F, depending on speed. So, if it's 40F outside and the air gets raised 5F to 15F, then the air coming out the vents is around 45F to 55F, and that's still a might chilly for my tastes. If it's 95F outside and it gets raised 5F to 15F then the air coming out of there is higher than my core temp, and so therefore it's trying hard to put heat into my body (like the convection oven).

My opinions about the vents:

1) If the temp is above about 80F degrees or so I definitely prefer them in the outboard position. I don't want the hot air hitting my shins.

2) If the temp is below about 60F degrees or so I definitely prefer them in the outboard position. I don't want the cold air hitting my shins.

3) If the temp is between about 60F and 80F I kinda don't care so I leave them in the outboard position since it's less work.

So, mine are in the outboard (open) position at all times. (In spite of those fugly exposed screw-holes.)

The EASY way to test on your own:

One problem with testing how something feels (or sounds, or tastes, or practically anything to do with our senses) is reproducibility. If there's too much time between 2 tests we tend to not be as able to accurately gauge the difference between 2 samples (some people are good at it (e.g. people with perfect pitch), but they're outside the bell curve). If someone replaced the light bulb in your garage with one that was 50 lumens brighter or dimmer while you were on vacation, would you notice? Almost certainly not, even if they told. But if you switched back and forth between the 2 lights in a very short period of time (e.g. less than a few seconds) then you almost certainly could tell the difference. The same is true for temps. If you let a few minutes go by, your perception of a previous temperature becomes less reliable to compare a new sample against. (I won't even go into the whole "power of suggestion" thing, which can throw some amazing monkey wrenches into experiments in which people are the sensors.)

It's been suggested to have one side vent be out and one side in. However, using 2 different limbs to measure a temperature isn't necessarily very reliable. That's easily testable: Filled a pan with 80F water and set it aside. Fill 2 other pans with water, one icy cold (full of chunks of ice) and the other fairly hot (105F to 110F). Put one hand into each of those extremes and let them sit there for a minute and then put both of them into the 80F water. Each hand will report to your brain a different story - the hand from the cold water will say that it's been put into very warm water, whereas the hand from the hot water will report that it's in rather cool water. Same water but measured by different hands with different experiences, yields different feelings.

What you CAN do is this (and I've suggested this same thing in several posts on the subject, though not with as much background detail): Put the vents in the outward (open) position. Get the engine up to operating temps by riding around for at least 10 minutes or so. Then get up to the speed at which you want to test. Then test by extending your legs out into the air stream for a minute or so. It's the same air, blowing past the same radiator and engine, but there's far less time for your legs to forget the previous test. If it's 100F outside and your legs tell you that having that 100F air that's been heated by the engine feels cooler to you then by all means stop and move the vents inward. My legs tell me that the air is trying to put heat into them, so I leave them in the outward position on hot days.

When it's 40F outside, it feels *to me* that the engine doesn't heat up the air enough for it to be comfortable, so I leave the vents out on those days as well. On those days between the extremes it kinda doesn't matter, so why go through the hassle of moving.

Of course, your milage (er... senses) may vary, and I can think of a few other minor issues with the experiment, but I still think that it's basically a good valid test. If you notice a difference then cool - act on it. If you don't then by all means leave the vents closed - I think it looks better that way (again, your senses may vary on that point as well :) )! I put forth the above explanations and tests that you can do yourself so that you can at least make an informed decision and test for yourself.

Bunsen

 
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It isn't even winter yet!!

Opening the vents doesn't 'direct' engine air per se. It creates a wider low pressure zone (the area inside the 'envelope' carved through the air by the moving bike). That will tend to draw (as in pull) more air from the engine compartment to compensate (fill the space) created by the open deflectors than it would if the deflectors were in. It also provides a wider 'protected zone' for the rider's thighs - they don't get as much direct air blown on them.

Doesn't do anything for cold hands.

 
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It wouldn't matter one bit which position they were in to me because if it's that cold, I'll have my ass in front of the fire place and not sitting on the FJR

 
Last time it was in the 40's I rode with one side open, and the other closed. I didn't notice much of a difference, so I switched it closed on one side, open on the other.
I think I need someone to secretly open one, and close the other. Then I should ride around with my eyes closed to decide which is better for cold weather. :unsure:
Let's not ride with your eyes closed :) I can tell you right now that I did feel the difference when it was 45 and one was closed and the other one wasn't. keep in mind that I basically have no natural insulation going on. :) and when it is 60 I ride in turtle-neck pulled to my eyes.

BTW. free Britney :crazy:

 
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i had to vote open cause i can tell a big difference now that the weather has turned a bit colder. but i really wanted to vote for pie

free britney was my second choice :p

 
Absentee here....not only because I have an 05 but because this poll is queer.

 
If it's below 40 you should be sitting in your living room, in front of the tube with a beverage of your choice, not worrying about the middle friggin cowl.

 
I voted "I'd rather have pie". I'm not all that fond of riding at 40 above zero! You da man! Be cafeful out there!

 
Alright... "Leave Britney Alone" is currently tied for 2nd place! :lol: ;)

 
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You Californians have too much heat over there! If we were to stop riding below 45 I would have to park my bike for 3-4 month.

 
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