Fuel cap on my R3 hissing

..Found this Article by Sonnie''

The fuel tank on the R3 is pressurized with a slow bleed system. A word of warning when filling the tank after a ride.
DO NOT remove the cap again after refueling a full tank of fuel. The engine heat expands the fuel surprisingly fast
in the tank after even a minute or two.. After picking up my new bike from the dealer i stopped to refuel after a 75 mile ride.
Topped off the fuel, put the cap back on and went in to pay. On returning to the bike i noticed just a very small amount of fuel
around the filler neck under the cap that probably dripped when i removed the nozzle. Instead of just using a piece of cloth to
absorb it, i made the mistake of removing the black fuel cap just partially to get under it, and whoosh, about 4 or 5 ounces of fuel
gushed out of the tank onto the bike. I was lucky it didnt ignite from the header heat as it was dripping down on them.
Never make that mistake again. Often in my garage i can hear compressed air being released from the cap with a hissing sound
every 20 seconds or so till the bike cools.

Not sure what the go is with this fuel issue you guys have got, but over the last few weeks we have had temps here well into the 40dg. Rode home from Perth in 46dg and there was no hissing of fuel from the tank. Some of you must have a faulty tank or blocked overflow. Only be a matter of time before the exhaust ignites that fuel spill.

Nungers said:

Not sure what the go is with this fuel issue you guys have got, but over the last few weeks we have had temps here well into the 40dg. Rode home from Perth in 46dg and there was no hissing of fuel from the tank. Some of you must have a faulty tank or blocked overflow. Only be a matter of time before the exhaust ignites that fuel spill.

Click to expand...

My first guess would be with @Mongler07 and @TURBO200R4 's suggestions about a kinked or blocked vent hose, but I've learned here some new things about the gas cap. I was having some minor hissing at one point and fiddled around the front right of the tank with the hose and it went away. I had recently had the tank off, so I figured I must have caused it when I reinstalled the tank.

Mine had the hissing/leaking. The dealer checked the vent hose and found it creased. Seemed to fix it. I also make sure to not fill the tank past the bottom of the neck per the manual.