FJRocket
Doctor Throckenstein !!!
A note... I think Mods posts should be placed under the Technical category instead of Parts, but heck thats what the main topics suggest, so here it is. This is about an engine heat reduction mod.
I was riding the other day in about 95 degree heat. The humidity was very high and the air seemed very stagnate, even at 65 mph. I was wearing shorts. I could not touch the tank. Usually I wear jeans and really don't notice the heat, but when I slowed down, the FJR kept hitting four bars. The heat was just pouring out and roasting my legs. And I could barely touch the tank, even when there was a bunch of fuel in it.
As some of you may know, I'm building an airplane. I bought scads of different types of heat and sound insulation for the project. I figured, what the heck, it'll work on the bike, too. I had read many posts about guys gluing new insulation to the bottom of the tank to at least keep that more under control. Well, I tried a bit of a different tack. And it worked quit well.
I had some aluminum faced, fire retardant, thermal insulation matting. You can get this stuff for cars. It's got fairly thick cloth matting behind the metal film, and there is stitching in the fabric. I used 3/8 inch thick material.
I popped off the black plastic tank skirts and took the tank bolts out. I put a stool on the left side of the bike and then flipped the tank over on it's side onto the stool. Poor thing looks like a drunken turtle over there! Anyway, I left everything hooked up fuel and electrical line-wise. The wires to the tank weren't run conveniently for what I was doing, so I disconnected them and re-ran them with the left main fuel line. Not a big change, but significant. The fewer cuts in the insulation, the better...
I cut some cardboard for a template and got an idea how much matting I would need. This matting is not rigid, but holds it's shape well. I shaped the carboard template on the bike and then sheared the insulation matting to match the shape I chose. I had to mark it and cut both a few times, but I finally got what I wanted.
I decided I did not want to glue parts, I just decided to make an engine bay "blanket". My goal was to cover everything over the engine and under the tank from the seat pan to the front of the frame where the tank bolts down. Well, I couldn't really cover everything and leave the ugly blanket sticking out, but I did get it to cover the vast majority of the places where heat was getting to the tank and out to my legs.
This idea is pretty simple. Start with a flat piece that is actually too big, then cut it back so it doesn't show. I did have to make 4 slices in it to get around the fuel lines and wires, as well as the rear tabs for the long bolt holding the tank down.
Once I got the general shape, I cut slots in the insulation for the fuel lines and fished the sheet of insulation through the middle. Surprisingly, it sits there quite well. NOTE: The left fuel lines are slightly aft of the right fuel line, so the cuts are not directly across form one another.
I thought about taping these slices closed, but I think there will be some overlap as well as the tank mashing them down. I want the blanket to be easily removable, too. I want to sync my throttle bodies again pretty soon, so I gotta get that thing off easily. Also, in the winter I WANT the heat!
With the flat sheet of insulation rough trimmed in place, I flipped the tank back into postion and simply mashed it down. I worked the tank back to postion and loosely bolted it back down. Then I marked the matting for trimming again. Much of the trimming could be accomplished with the tank in place.
I left the rear corners of the insulation matting square. I then folded the corners and tucked them down and a bit under the painted panels that are under the black tank skirts. I trimmed the matting so it would not show under the black tanks skirts and re-bolted everything. Worked like a charm! Took about 1 hour.
In addition to the engine bay blanket, I also closed off a bunch of the gaps in the rear upper area of the fairing. It looks kind of silly, but it was just a test. I bought $2.17 worth of 1/2 inch hot water pipe insulation. There were four of those thick foam tubes that you tape over the pipes in each package. I used two of them. Now the packaging says the stuff works to about 240 degrees F, so I was concerned about the stuff melting. So far so good, but you may not want to try this, it could be disastrous!
Again, I wanted something just to test, and something removeable. First thing I did was cut a piece to put between the fairing and the bike along the upper rear boarder of the fairing. The insulation tubes are slotted, so I just slid the slot along the fairing and the round tube insulation is held in place nicely. It shows, and it looks a little geeky, but its just a test. Next, I fed more pieces up under there to close off as much airflow back to my legs as possible. I used three additional cut sections of the foam behind the fairing to block the airflow to the rear area escaping to my things as much as possible. All the pieces are at the top and kind of in the rear "apex" of the fairing, aft of the vent slots. Once I had the insulation pieces tucked into place, I went out for a 100 mile test ride.
The results of all this is excellent. Pros: cheap and easy, removable, and it works. Cons: the pipe insulation looks dorky where you can see it (which you do have to look for it), and the engine does get to 3 bars a little easier. I did not block the side vents, the air can still go from the radiator to the engine, then out the sides and bottom. But it is substantially blocked the heat to my legs and the tank.
The frame still gets very hot. Those black rubber covers under the lower sides of the tank at the level of the frame are still extremely hot. I notice hot airflow from them. I will remove the tank again and try to get some matting or something else under there to improve that sitution.
The insulation material I used is called The Insulator. I used the single sided material, with foil on one side only.
I was riding the other day in about 95 degree heat. The humidity was very high and the air seemed very stagnate, even at 65 mph. I was wearing shorts. I could not touch the tank. Usually I wear jeans and really don't notice the heat, but when I slowed down, the FJR kept hitting four bars. The heat was just pouring out and roasting my legs. And I could barely touch the tank, even when there was a bunch of fuel in it.
As some of you may know, I'm building an airplane. I bought scads of different types of heat and sound insulation for the project. I figured, what the heck, it'll work on the bike, too. I had read many posts about guys gluing new insulation to the bottom of the tank to at least keep that more under control. Well, I tried a bit of a different tack. And it worked quit well.
I had some aluminum faced, fire retardant, thermal insulation matting. You can get this stuff for cars. It's got fairly thick cloth matting behind the metal film, and there is stitching in the fabric. I used 3/8 inch thick material.
I popped off the black plastic tank skirts and took the tank bolts out. I put a stool on the left side of the bike and then flipped the tank over on it's side onto the stool. Poor thing looks like a drunken turtle over there! Anyway, I left everything hooked up fuel and electrical line-wise. The wires to the tank weren't run conveniently for what I was doing, so I disconnected them and re-ran them with the left main fuel line. Not a big change, but significant. The fewer cuts in the insulation, the better...
I cut some cardboard for a template and got an idea how much matting I would need. This matting is not rigid, but holds it's shape well. I shaped the carboard template on the bike and then sheared the insulation matting to match the shape I chose. I had to mark it and cut both a few times, but I finally got what I wanted.
I decided I did not want to glue parts, I just decided to make an engine bay "blanket". My goal was to cover everything over the engine and under the tank from the seat pan to the front of the frame where the tank bolts down. Well, I couldn't really cover everything and leave the ugly blanket sticking out, but I did get it to cover the vast majority of the places where heat was getting to the tank and out to my legs.
This idea is pretty simple. Start with a flat piece that is actually too big, then cut it back so it doesn't show. I did have to make 4 slices in it to get around the fuel lines and wires, as well as the rear tabs for the long bolt holding the tank down.
Once I got the general shape, I cut slots in the insulation for the fuel lines and fished the sheet of insulation through the middle. Surprisingly, it sits there quite well. NOTE: The left fuel lines are slightly aft of the right fuel line, so the cuts are not directly across form one another.
I thought about taping these slices closed, but I think there will be some overlap as well as the tank mashing them down. I want the blanket to be easily removable, too. I want to sync my throttle bodies again pretty soon, so I gotta get that thing off easily. Also, in the winter I WANT the heat!
With the flat sheet of insulation rough trimmed in place, I flipped the tank back into postion and simply mashed it down. I worked the tank back to postion and loosely bolted it back down. Then I marked the matting for trimming again. Much of the trimming could be accomplished with the tank in place.
I left the rear corners of the insulation matting square. I then folded the corners and tucked them down and a bit under the painted panels that are under the black tank skirts. I trimmed the matting so it would not show under the black tanks skirts and re-bolted everything. Worked like a charm! Took about 1 hour.
In addition to the engine bay blanket, I also closed off a bunch of the gaps in the rear upper area of the fairing. It looks kind of silly, but it was just a test. I bought $2.17 worth of 1/2 inch hot water pipe insulation. There were four of those thick foam tubes that you tape over the pipes in each package. I used two of them. Now the packaging says the stuff works to about 240 degrees F, so I was concerned about the stuff melting. So far so good, but you may not want to try this, it could be disastrous!
Again, I wanted something just to test, and something removeable. First thing I did was cut a piece to put between the fairing and the bike along the upper rear boarder of the fairing. The insulation tubes are slotted, so I just slid the slot along the fairing and the round tube insulation is held in place nicely. It shows, and it looks a little geeky, but its just a test. Next, I fed more pieces up under there to close off as much airflow back to my legs as possible. I used three additional cut sections of the foam behind the fairing to block the airflow to the rear area escaping to my things as much as possible. All the pieces are at the top and kind of in the rear "apex" of the fairing, aft of the vent slots. Once I had the insulation pieces tucked into place, I went out for a 100 mile test ride.
The results of all this is excellent. Pros: cheap and easy, removable, and it works. Cons: the pipe insulation looks dorky where you can see it (which you do have to look for it), and the engine does get to 3 bars a little easier. I did not block the side vents, the air can still go from the radiator to the engine, then out the sides and bottom. But it is substantially blocked the heat to my legs and the tank.
The frame still gets very hot. Those black rubber covers under the lower sides of the tank at the level of the frame are still extremely hot. I notice hot airflow from them. I will remove the tank again and try to get some matting or something else under there to improve that sitution.
The insulation material I used is called The Insulator. I used the single sided material, with foil on one side only.
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