Boiling Gasoline in Gen I (05)

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Open the cap slowly and release the pressure. You will still hear the gas boiling but it won't jump out at you.

 
I think that is what I will have to do until I get home. Just another 2500 miles to go that's all...

 
Happened to me in 2003 through NV when it was 110 (actually hotter on the road than that official temp). Had been running tank-to-tank and got a face full of gas. Only my prescription glasses saved me from serious shyte. It was when I got home that I dug and made the Fuel Filler Neck tech tip page. It was either a clogged drain tube or passage in the cap. Since then I always unlock it slowly when it's hot outside; just in case but it's never happened again once I do the FFN yearly.

https://www.fjr-tips.org/maint/ff/ff.html

 
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Hard to imagine that the fuel was actually boiling. Vapor pressure may be the culprit. The vapor pressure of the gas at elevated temperatures can cause an increase in the pressure inside the tank at temperatures WAY below the boiling point.
Gasoline is a mixture of a large number of hydrocarbon compounds. It has a boiling range that starts as low as 90-95 °F and the boiling point will rise to something like 400 °F as the more volatile components go off. Under the pressure of the tank, the boiling point rises (higher BP at higher pressure). When the pressure is released (and the fuel temperature is greater than the BP), it will certainly boil and possibly erupt. No question that the temperature of the gasoline will exceed the BP on a warm day; especially on a Gen I without an added heat blanket.

 
Strange. I'm used to my groin getting cooked by a hot tank, but never considered surgery. ("Ballectomy." Ouch. I thought the vasectomy was unpleasant enough.as an option.) *head scratch*

I'm convinced part of the problem is that fuel is pumped from the fuel tank to the injectors and back into the tank after its cooked by the engine. Is that the case on subsequent generations as well?

+1 on opening the gas cap slowly. I always do that.

 
Doesn't the Gen 2 have the same engine as the Gen 1? If so, what is the difference between this happening to a 1 vs 2? More room between engine & tank maybe?

 
Doesn't the Gen 2 have the same engine as the Gen 1? If so, what is the difference between this happening to a 1 vs 2? More room between engine & tank maybe?
The Gen I uses a fuel return line from the fuel injector rail to the gas tank for fuel pressure regulation, the Gen II doesn't do this. The fuel return line lets the gas pick up heat from the engine before being returned to the tank. The Gen II comes with a heat blanket between the engine and the gas tank, revised body panels which helps manage heat, different radiator and an apparent corporate intention to design the FJR for better heat management.

 
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Doesn't the Gen 2 have the same engine as the Gen 1? If so, what is the difference between this happening to a 1 vs 2? More room between engine & tank maybe?
Apart from the fuel flow bit, the engines are essentially the same, but insulation and airflow are very different, that's where the Gen II scores.
Engine management is different, but if anything the later ones run weaker, so hotter.

The throttle response was made too abrupt on the'06 & '07, The '08 and on are much better, probably the same as the Gen I's response. So recommendations tend to be for '08 or later, but that's driveability, not temperature.

 
I got my Foil insulation kit and dropped it on my bike - drastic difference in heat from the engine adding to the tank....

I would say as a whole on a HOT day, that there is roughly a 15 degree difference then what I had before...

Does it still get warm yes, but I have driven this way for the last 5 years, and it didn't kill me, but the cooler tank is a welcome upgrade.

With that said, it will stay on the bike in the warmer temps, but the insulation will be removed for colder riding weather, where that nice warm tank is a huge plus.

Got mine from Ebay from the guidance of another member here....

Search Google for

NEW YAMAHA FJR1300 FJR HOT TANK HEAT FIX INSULATION KIT

 
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Heh. Definitely not. Most of the time I prefer to ride/drive my vehicles into the ground. That said, my wife has told me that if I sell my old M3 ragtop (which can't pass smog without spending more on it than it's worth), my XR600R (plated) and her Ninja 250 I can add a BMW 1200 GS Adventure to the garage. I like the idea of a GSA and FJR in the garage.

Is the Gen 2 cooler than Gen 1?
Absolutely! Upgrade to a GEN II (08 or newer) and never look back...

--G
 
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