The Heat is Tamed!

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Does anyone know if the windshield mod that several riders have tried (cut holes at the bottom of the shield like the Cal scinetific model) also helps with the heat issue at the rear of the fuel tank?

When I ride I hold my left hand down by my knee and direct "scoop" air on to my crotch. If I sit back slightly back from the tank I can feel the cool air go up my left leg, accross the tank and exit on the inside of my right leg. I woulder if the wings provide the same cooling effect???

 
I tried removing the rubber thingy's...increased the temperature on my left leg by about 15 degrees. Decided to put them back in after about 45 minutes.

I think the wings are working by catching the air coming off the fairing and redirecting it back around the fairing. It is entering the cockpit well forward of the tank. I can feel the wind stream in as far in as the edges of the steering head. I think air is getting under the front lip of the tank and driving the warm air out. Along with the heavy slipstream over the tank I think the tank is now acting as a radiator. The heat is being stripped faster than it is entering the tank and the result is a cool tank, even with the sun beating on it.

You can close the wings in the cold weather to keep cold air off the lower body. I tried that this AM on the way into work. It appears that it will extend the riding season for me here in the northern US.

Our prototype mount lets us figure out and adjust angles, etc. I think our final mount will be a real simple one piece design that will mount below the stalk, FZ or stock.

 
Odot,

I am going to send the original cardboard and duct tape versions I used for my initial feasibility testing to FGRMGM. He can take a fizz can and paint them to match his bike. As much as he likes these he will really love those ones! :p

 
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FWIW -

The low pressure caused by the windscreen sucks the air up through the fairing steering well that should be forced through the radiator. Put your hand down there at speed. We need a shield that at the bottom or the steering stem to close off this airflow. The fairing holes or your wings are needed to fill in the low pressure.

 
Are you going to have a show at wfo? Am actually considering going there...provided that wild hair up my *** has money.

 
WFO is going to be the final test. At this time we are considering a southerly route through Colorado and then thru southern Utah(Canyonlands, Arches, Capitol Reef, Grand Staircase, Bryce) to the Loneliest Highway. It should be a formidable test. Probably will stay with the prototype mounts for this trip so I can adjust the wings on two axis to find the optimal position.

 
-sounds promising...keep us informed...are you currently using any other heat mods with this set-up, or did you remove all those after installing this?

 
Bottom of the tank was insulated this winter with the aluminized stick on stuff from the auto store. That's it other than the wings.

 
I tried removing the rubber thingy's...increased the temperature on my left leg by about 15 degrees. Decided to put them back in after about 45 minutes.
I think the wings are working by catching the air coming off the fairing and redirecting it back around the fairing. It is entering the cockpit well forward of the tank. I can feel the wind stream in as far in as the edges of the steering head. I think air is getting under the front lip of the tank and driving the warm air out. Along with the heavy slipstream over the tank I think the tank is now acting as a radiator. The heat is being stripped faster than it is entering the tank and the result is a cool tank, even with the sun beating on it.

You can close the wings in the cold weather to keep cold air off the lower body. I tried that this AM on the way into work. It appears that it will extend the riding season for me here in the northern US.

Our prototype mount lets us figure out and adjust angles, etc. I think our final mount will be a real simple one piece design that will mount below the stalk, FZ or stock.
Nice work. I like what you've come up with. As to the rubber thingies, did you take them off independently of the wing mod or in conjunction with it? I took mine out and put them back in a week later, but I'm considering taking at least one out again, just to let some of the heat out.

 
The tank heat is for the most part a result of the fuel return coming off the press regulator. The constant flow and return gathers heat present in the rail area and sends it via the fuel into the tank, which, with a closed circuit, would explain why the tank gets warmer as the level gets lower. As such, insulating the bottom of the tank has had limited success, though it of course has to help some, it's not the final solution. I would use the wings, as long as the mount was a little less clunky looking, like the mirror base mounts mentioned. I've considered experimenting with a small Ford PS cooler I have, routing the return fuel through it. Fear of fire has prevented me from implementing this mod, any routing outside the frame is chancey at best. And I had similar poor results removing the rubber tank fillers-mega btu's from the spaces, no improvement in any way I could tell.

 
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if you are running the original 03-05 windscreen on your FJR then taking out the rubber thingies will most likely result in more heat in your crotch area due to the air flow.

When I had the stock screen on I kept getting dust and grit in my eyes, not to mention the dreaded "push" on the back at speed, but as soon as I switched to the C.B. +2+2 with flip that all went away. The airflow with the stock screen is, ummmm, sub-optimal...

As far as removing the rubber thingies and it not making any difference in how hot the tank gets - B.S. I was on a ride with three other FJR owners and we stopped to get gas - all with about the same left in the tank - and my tank was warm, theirs were all HOT and boiling the remaining gas. They were convinced when they touched my gas tank and then theirs.

 
Sounds like the thing to do is remove the rubber thingies, install wings, change the windscreen, add ice, stir and enjoy!

 
if you are running the original 03-05 windscreen on your FJR then taking out the rubber thingies will most likely result in more heat in your crotch area due to the air flow.
When I had the stock screen on I kept getting dust and grit in my eyes, not to mention the dreaded "push" on the back at speed, but as soon as I switched to the C.B. +2+2 with flip that all went away. The airflow with the stock screen is, ummmm, sub-optimal...

As far as removing the rubber thingies and it not making any difference in how hot the tank gets - B.S. I was on a ride with three other FJR owners and we stopped to get gas - all with about the same left in the tank - and my tank was warm, theirs were all HOT and boiling the remaining gas. They were convinced when they touched my gas tank and then theirs.
Well, BS back atcha. Though it might appear so, my filler removal comments reflected an overall lack of improvement in heat troubles, not specifically the tank temp. Makes sense though, a flow of air through and around the rail would lower fuel temps, as well as under tank temps overall, but the huge amount of heat flowing out and directly onto my legs made for a no go overall for me.

 
Radman - what are you doing discussing heat in the FJR anyway?

You live in Minnesota and it only gets warm there three times a year, right?

It could be your knees are closer to the rubber thingie vents than mine are so it isn't workable for you and others.

Just kidding - as always with this stuff YMMV.

What's good to me is totally wrong for another and vice versus. Kinda like asking if the stock saddle is comfortable.

As with any vehicle, it's the total combination that makes or breaks it.

 
I hope you aren't getting too hung up on the mounting brackets. :unsure: It is a PROTOTYPE that allows me to adjust position of the wings in and out on the stalk, the axis angle of the wing mount, height position of the wing relative to the fairing, etc. I didn't intend to make the perfect bracket from the get go. Too expensive to do that. I need to see where things need to be to work first! An engineer would actually appreciate the simplicity of the design as a tool for testing until we get to the final specs. (My neighbor who IS an engineer even thought they were pretty well thought out for what we are trying to do...) The wings actually look pretty cool on the bike IMHO. :D

I have a couple of designs for the final mount in mind. :ermm:

To me clamp ons look cheesy but some like'em. One design under consideration is like a big flat pliers. The mounting bolt for the wing, the six sided thing in the picture extending down to the wing, will be the thing that tightens the "pliers" grip around the stem. No other bolts. In black.

I am going to make a beautifully machined mount for me that will appear to be nothing more than a blister(even painted black!) on the bottom of the stem with the wing bolt attaching directly to it when I have the thing the way I want it. :yahoo:

 
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60 mile ride yesterday in low 80's heat. Two bars showing on the gas gauge. Tank was as cool at the end of the ride as it was when I pulled the Cooker out of the garage. I played around with the wing axis. Moving the bottom of the wing in and moving the wings to their maximum effect position pushes so much air into the cockpit it was causing my helmet to lift. Adjusting the axis slightly (maybe 5 degrees) outward and reducing the wing attack angle resulted in a very comfortable cockpit and the warm air that still wafts out around my left ankle was even less pronounced. It appears that vertical or slightly outward angled wings has the most effect.

I also experimented last evening with the position of the wing on the stalk. The further out I position the wing on the stalk the less effective it is at removing the heat from the tank, although it still is comfortable.

I'll post more results as I get them. I better get a few things off the honeydew list tonite or I may not get to ride for a few days. :D

 
I posted a note recently asking about vendors that made these things. The only one I know about is Baker. How about an existing product that could be mounted diretly to the fairings? Any other manufacturer's out there besides Baker?

Pappy

 

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