Fuel Cap Pressure.

[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.

 

[dougl]

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.

Aren’t the vapors supposed to go into the EVAP system?

 

[sonnie]

Aren’t the vapors supposed to go into the EVAP system?

They dont on mine.. Maybe has something to do with the fuel injection system. I also have a T-120 Bonneville with fuel injection
and it doesnt build pressure like the Rocket.. at least i dont notice it when i take the cap off to refuel.. When i remove the cap on the Rocket
with very little fuel in it, i dont notice any pressure, only when topped off to the fill mark. You can hear an audible hiss when the tank is full
after riding it for a few miles and parking it. It seems to release the pressure in short bursts..

 

[Zutt]

I thought there was something wrong with my cap because of the hissing sound. And when stopping to fuel, when I open the cap (tank near empty) I can hear the sudden release of pressure.

Thanks for the tip!

 

[Mighty Mouse]

They dont on mine.. Maybe has something to do with the fuel injection system. I also have a T-120 Bonneville with fuel injection
and it doesnt build pressure like the Rocket.. at least i dont notice it when i take the cap off to refuel.. When i remove the cap on the Rocket
with very little fuel in it, i dont notice any pressure, only when topped off to the fill mark. You can hear an audible hiss when the tank is full
after riding it for a few miles and parking it. It seems to release the pressure in short bursts..

This was the same problem I had with my GT. After I filled up and returned home a few miles I was going to put some Sea foam in as I do every few fill-ups. A gusher of gas came out and I was lucky nothing caught fire. I took it in as the dealer thought it was the EVAP system. After a few days Triumph told me I needed a new gas tank as the EVAP was fine. Now I can fill it up ride 3 miles home in 110* heat and take off the gas cap no problem. The most I get is a tiny hiss and that's it upon release of the cap. It may be your tank and I wouldn't settle for what's going on with your Rocket. It's the EVAP or the tank. Tell them it's a safety item and under warranty they should fix it. Good luck.

 

[pica]

Let me renew my fire extinguisher before I test this...

 

[vsteel]

I can get pressure but I don't want to change it. My first Tiger had an issue where it would put so much fuel into the evap system and make it not start or kill the bike if it was idling. Run really rough on those 100+ days. I like the bike how it is now runs like clockwork no matter how hot it is.