Beat the heat

I hate to bore all the new 06 owners with the subject of heat on the 03/04/05's but...they are still pretty warm and it is summer again.

While I had my FJR apart this winter I looked carefully at where the hot air flow paths were. I've done all the previously mentioned heat fixes and still considered my bike pretty warm, especially at low speed in traffic. I made a few additional changes that seem to be working excellently.

As Rad mentioned the elimination of the cat with the Dale Walker pipe really seemed to help, especially when stopped in traffic. It does make an improvement.

What I gleaned from looking at Yamaha's design is that they intend for the air to go thru the radiator, get deflected downward by the black curved plastic panel behind the radiator, down over the pipes and out the vents along the sides. Somehow this airflow path gets bypassed and comes out under the tank and onto the rider.

To help with the heat while moving problem I took the black plastic panel that sits behind the radiator and added foam tape to the sides and edges to completely seal it into the recess in the frame above the engine. The part seems to be intended to do just that but there are just too many gaps and the part flexes and does not seal the way it is mounted. In addition to the foam tape I added a stiffening rib out of light aluminum and added an additional "mount" in the middle to pull it into the opening. This was simply two holes drilled in the plastic and a tie wrap laced thru the holes and around one of the air fittings on the cam cover. This seals up the opening between the head and the frame and holds the seal in place securely.

Next, I tried to figure a way to make sure the hot air from the radiator and pipes exited thru the vents along the side. Rather than try and force it thru there, I added some aluminum deflectors or spoilers to slightly disrupt the air flow over the vents or gills and creat a low pressure area behind the foils to suck the hot air out of that cavity.

Voila:



From the front you can see how much the tabs or spoilers stick out:



The tabs are just some 2 inch wide strips of .030 aluminum sheet bent with a .5 inch edge and cut to length. They are attached with trim tape or double sided foam tape:



I've played around with these and they seem to work quite well. I used strips of yarn to see what the air flow pattern was around them and they do need to stick out about an inch from the surface of the fairing to catch the air and create a low pressure area. Possibly this is the short coming of the Yamaha approach as is because the gills do not seem to have any low pressure behind them to suck the hot air out and rather rely on pressure from the radiator flow path to push the hot air thru. It goes under the tank and onto the rider instead.

Soo.... any takers to try this and see what you think? I am convinced that it helps and my bike is as cool or cooler than anything I have ever ridden. I can feel the hot air flowing from the gills now where, before, it was hard to tell if anything was flowing out the gills. I haven't been in really hot weather here in Michigan, yet, so that is why I'm interested in some others experience.

It is pretty easy to cobble up if you can get some strips of thin aluminum, bend the tab along one edge, cut to lengths that fit the curvature of the openings and attach with two sided tape.

I'm still experimenting with mine so I'm not to the stage of pulling it all off, primping and painting, etc. to make it look better. They aren't the prettiest addition but do have a sort of functional appeal to me that will look nicer cleaned up and painted.

I'm also curious to see how they work for anyone else who hasn't sealed up the panel behind the radiator. I think that is important but the tabs seem to add quite a bit of hot air flow thru the gills that wasn't there before (testing by feel, with yarn and with thermocouple prove this) so maybe that is sufficient to suck most of the hot air out of the area behind the radiator without further sealing.

Cool idea Jestal - keep us posted on the really hot days this Summer. Makes sense to me, but it's not an overly beautiful addition to our sleek FJR's (but not fugly either...)

Those look like little spoilers..... :huh:

Very nice idea, but as you and others have said, not very attractive. Too bad they need to be so large to be effective. I may try to seal up the air flow as you describe but I'm not sure I want to add the spoilers.

Yea, they are little spoilers. Just like the duck tail on a 'Cup car pulls the rear of the car down by creating negative pressure they create negative pressure to evacuate the hot air.

They do need to stick out that far. I did a little measuring of the boundary air layer with tuffs of yarn taped to pieces of wire sticking out at those areas and they need to be out 3/4 to 1 inch to really pick up any air.

It is surprising the hot air flowing out the gills now when you put your hand down there while riding.

I like the yarn idea most of all. No doubt the folks in your neighborhood are used to such oddities pulling outta your garage, as are mine. But I bet it would work better than Yorkies for yankin' in the babes........

The mad engineer is at it again, great work Jestal! Think I'll pass though, the little spoilers would really stick out on an 05 and I only notice any heat at all when I'm stopped or going really slow in traffic and I don't think the spoilers would help much then. Keep up the good work!

Way cool... not too sure what mods were don to my bike... I know I have a piede of innands from somewhere, and the foil thingy was done, but it's still kinda hot...

think I'll try that since I'm planning on riding thru the desert...

Just read a thread in another forum about how to stay hydrated, too....

so more air would be a good thing... even 120 desert temps should be cooler than what's coming off that engine.

thanks

Mary

I seem to recall that Cal Sci. used to sell something called "Hot Wings" that looked a lot like Jestal's... their website doesn't show them any longer for the FJR, but they still have something similar for the ST1300....

Groo said:

I seem to recall that Cal Sci. used to sell something called "Hot Wings" that looked a lot like Jestal's... there website doesn't show them any longer for the FJR, but they still have something similar for the ST1300....

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Groo.... I tried them last summer & found they didn't make a significant difference...not worth the dough....

Hey Jestal, can you set those wings up so that they extend and retract depending upon air velocity and temperature? You do good work and they're a good idea. I may try them myself.

I've been monkeying around with the heat issue on my '04 over the past week or so as well, after a weekend of unexpected hot riding in Michigan's Upper Peninsula. I started by insulating the bottom of the tank. I really hadn't noticed too much of a problem there (I mostly felt it on my legs) in spite of the fact that I sit close to the tank, but it seemed like something should be done there anyway. I also removed the little rubber covers on either side of the tank, but put them back on a day or so later, as a lot of heat was coming out (a good thing) onto my legs (a bad thing). So I then raised the front of the tank about a quarter of an inch, so at least some heat can get out.

Then what I did, using Cromeit's (sp?) left-side fix as inspiration, is cut some foam and put it in behind the vents in the frame between the frame and engine, which forces the air to come out through the vents. Then to force it out the gills in the fairing I put foam at the rear of the gill between the fairing and the frame. Finally, I put foam between the fairing and frame all along the sloped edge wherever there was a gap. I cut and shaped the foam using a bandsaw, and it still needs some tweaking and shaping, after which I'll glue it to the inside of the fairing.

The last thing I did was also based on Cromeit's fix. He'd suggested entirely removing the air deflector to the left of the radiator. For those less inclined to hack away 3/4 of the deflector, he offered a second alternative where only half of it was cut away. I took it a step further and just cut out an area about 3x3, which allowed me to leave all the mounting screws alone and kind of maintain the integrity of that whole assembly. The cutaway portion lines up perfectly with the vents in the frame and the gills, so air moves through that area and is carried right out the gills.

I took it for a ride last night, and there's now basically no excess heat on the left side (there'll always be some heat, but my VFR used to cook my ankles too...) The difference is such that now the right side seems hot whereas before it felt cool compared to the left, so that'll come next.

Kilroy said:

I've been monkeying around with the heat issue on my '04 over the past week or so as well, after a weekend of unexpected hot riding in Michigan's Upper Peninsula. I started by insulating the bottom of the tank. I really hadn't noticed too much of a problem there (I mostly felt it on my legs) in spite of the fact that I sit close to the tank, but it seemed like something should be done there anyway. I also removed the little rubber covers on either side of the tank, but put them back on a day or so later, as a lot of heat was coming out (a good thing) onto my legs (a bad thing). So I then raised the front of the tank about a quarter of an inch, so at least some heat can get out.
Then what I did, using Cromeit's (sp?) left-side fix as inspiration, is cut some foam and put it in behind the vents in the frame between the frame and engine, which forces the air to come out through the vents. Then to force it out the gills in the fairing I put foam at the rear of the gill between the fairing and the frame. Finally, I put foam between the fairing and frame all along the sloped edge wherever there was a gap. I cut and shaped the foam using a bandsaw, and it still needs some tweaking and shaping, after which I'll glue it to the inside of the fairing.

The last thing I did was also based on Cromeit's fix. He'd suggested entirely removing the air deflector to the left of the radiator. For those less inclined to hack away 3/4 of the deflector, he offered a second alternative where only half of it was cut away. I took it a step further and just cut out an area about 3x3, which allowed me to leave all the mounting screws alone and kind of maintain the integrity of that whole assembly. The cutaway portion lines up perfectly with the vents in the frame and the gills, so air moves through that area and is carried right out the gills.

I took it for a ride last night, and there's now basically no excess heat on the left side (there'll always be some heat, but my VFR used to cook my ankles too...) The difference is such that now the right side seems hot whereas before it felt cool compared to the left, so that'll come next.

Click to expand...

Kilroy-

Ideas sound good, any pictures to pass along?

Thx.

jestal, could the same be accomplished with a one-piece spoiler covering all the same area, or are the seperations functional? Just thinking that one piece, although much harder to fabricate, would be more asthetically appealing and blend better with the look of the bike.

Jestal, I had made up the same kind of thing you did. I only got as far as cardboard mock ups before I decided whatever I made would not look good enough and I didn't want to make any mods that I couldn't take back off.

Looking at yours though got me thinking about clear plexiglass wings that would at least be transparent. I think your idea is solid, just getting it asthetic is my problem. Your's don't look bad, but they are reminiscent of the air brakes on an F86 Sabre.

What about a piano style hinge that allows them to fold up out of the way? I guess you could just make them with and extra fold that lets you clip them on the fairing and take them off when you want.

I'm just too image consious I guess.

Your an engineer, what about scoops on the outside of the fairing near the edge of the outer gill opening that would act like a veturi and put a stream of low pressure air at the opening. Just thinking you could make that look better than wings, but a lot more work. Just ramblin.

Ramblin Man said:

Looking at yours though got me thinking about clear plexiglass wings that would at least be transparent.

Click to expand...

Now you're reading my mind. Except paint 'em.

I have a heat gun and a sheet ready.

Additional question: from the attachement point orientation, what angle is the bend and is the bend required?

If I were an 03-05 owner, I would take a real close look at the heat sheild design on the 06 and consider trying to make one similar to fit.

The way this shield works, is by having an air gap both above and below it, so there is no direct contact with it to either the tank, or the cylinder head. Air is also introduced above the heat sheild and flows between it and the tank.

I suspect if you could make a heat shield that would float between the tank and frame/engine that you could dramatically reduce the amount of heat that gets transferred to the tank. The problem with a heat shield applied directly to the bottom of the tank is that it allows direct transfer of heat into the bottom of the tank. It needs an air gap to isolate the shield from the tank. I suspect this is one of the biggest reasons the 06 doesn't get the tank hot like previous years did.

I think you got a product you could take to market if you can get it into production.

Superb idea making cardboard mock-ups before fashioning metal or plexiglass pieces.

I have been toying with the idea of making a mod on my '06.

Different animal, I don't intend to hijack this thread, but I appreciate the ideas you gave me. :assassin:

(And that's what this board is for, right, not to spread lascivious lies and tall tales?) h34r:

There is still a fair amount of heat exiting under the left cowling on the '06.

I figure this could either be diverted from the rider's leg, or cool air could be inducted in beforehand.

O well, it's time to head for home now, and I brought the feejr to work today, happy me. B)

I'm confused. Red buttons help with the heat??