CB cuts out while riding

[rboe]

I find that topping the tank to the max is OK when in Nevada were you may need the extra margin of error or any time you touring as you'll bun off the gas before expansion problems show up.

But to top it off and park in the sun will give you problems as you've found.

[PrecisionMike_imp]

Hi to all. I'm new to the forum and my CB1100RS. I've been riding g for 50 years and raced for 16 of them and have had many many bikes over the years! I just refiuelled the 1100 for the first time and was surprised to see and hear a significant pressure release when opening the fuel cap. Has any one e experienced this....Is it normal. All comments very much appreciated!

[Cormanus]

Welcome to the forum, PrecisionMike.

[pdedse]

Hi to all. I'm new to the forum and my CB1100RS. I've been riding g for 50 years and raced for 16 of them and have had many many bikes over the years! I just refiuelled the 1100 for the first time and was surprised to see and hear a significant pressure release when opening the fuel cap. Has any one e experienced this....Is it normal. All comments very much appreciated!

Was it a warm day? I think I've noticed that a bit when it's hot outside, or maybe even when I've been riding for awhile, the bike is very warm.

[max]

Mike just to clarify; did the pressure escape from the tank or did the fueltank " inhale " the air?

And do you have a charcoal canister ( i think it is mounted behind the engine in between the swingarm ) which is part of a fuel vapour collection system called "evap"?

Like in this link
https://www.partsfish.com/oemparts/a/hon...e/canister

[PrecisionMike_imp]

Hi to all. I'm new to the forum and my CB1100RS. I've been riding g for 50 years and raced for 16 of them and have had many many bikes over the years! I just refiuelled the 1100 for the first time and was surprised to see and hear a significant pressure release when opening the fuel cap. Has any one e experienced this....Is it normal. All comments very much appreciated!

Was it a warm day? I think I've noticed that a bit when it's hot outside, or maybe even when I've been riding for awhile, the bike is very warm.

Was it a warm day? I think I've noticed that a bit when it's hot outside, or maybe even when I've been riding for awhile, the bike is very warm.
Hi. Thanks for your response. It was a cold day., approx 8 deg C. I had ridden about 25 miles and engine was at temperature. Definitely a pressure escape. I saw a cloud of vapour about 1 inch high. It deposited a slight mist on the paint. It's a Euro 4 bike so it does have an EVAP SYSTEM with charcoal canister. I know the PCM controls the purge valve which allows the vapour from the canister to be drawn into the engine but I dont know what parameters are used in the software to energise that solenoid operated valve. I suspect the either there is a fault or one of the parameters threshold was not reached....mst be ambient air temperature. ????

Mike just to clarify; did the pressure escape from the tank or did the fueltank " inhale " the air?

And do you have a charcoal canister ( i think it is mounted behind the engine in between the swingarm ) which is part of a fuel vapour collection system called "evap"?

Like in this link
https://www.partsfish.com/oemparts/a/hon...e/canister

Hi. Thanks for your response. It was definitely an escape and it does have a canister.

Hi. Thanks for your response. It was a cold day., approx 8 deg C. I had ridden about 25 miles and engine was at temperature. Definitely a pressure escape. I saw a cloud of vapour about 1 inch high. It deposited a slight mist on the paint. It's a Euro 4 bike so it does have an EVAP SYSTEM with charcoal canister. I know the PCM controls the purge valve which allows the vapour from the canister to be drawn into the engine but I dont know what parameters are used in the software to energise that solenoid operated valve. I suspect the either there is a fault or one of the parameters threshold was not reached....mst be ambient air temperature. ????

[Lord Popgun]

PM,

The evap system is not pressurized. Vapors flow from the tank to the canister and to a hose that comes out under the bike.

There is another inlet for letting in fresh air when the Evap Purge Control Solenoid Valve opens and vapers are pulled into the throttle body.

I suspect that your vent hose is pinched or something under the tank. Wouldn’t be the first time its happened here. I would lift the tank and check the hose and make sure its good when putting the tank back.

If you have a manual, look in section 1 for a drawing and explanation of the system.

[PrecisionMike_imp]

PM,

The evap system is not pressurized. Vapors flow from the tank to the canister and to a hose that comes out under the bike.

There is another inlet for letting in fresh air when the Evap Purge Control Solenoid Valve opens and vapers are pulled into the throttle body.

I suspect that your vent hose is pinched or something under the tank. Wouldn’t be the first time its happened here. I would lift the tank and check the hose and make sure its good when putting the tank back.

If you have a manual, look in section 1 for a drawing and explanation of the system.

Thankyou for the info. I'll check it out over the next day or so and post an update.

[PrecisionMike_imp]

PM,

The evap system is not pressurized. Vapors flow from the tank to the canister and to a hose that comes out under the bike.

There is another inlet for letting in fresh air when the Evap Purge Control Solenoid Valve opens and vapers are pulled into the throttle body.

I suspect that your vent hose is pinched or something under the tank. Wouldn’t be the first time its happened here. I would lift the tank and check the hose and make sure its good when putting the tank back.

If you have a manual, look in section 1 for a drawing and explanation of the system.

Thankyou for the info. I'll check it out over the next day or so and post an update.

Thankyou for the info. I'll check it out over the next day or so and post an update.
Hi . Problem solved and I suspect it might solve some folks stalling and poor idle issues. To recap my tank has what I consider to have excessive internal pressue which is seen to escape when opening the fuel filler cap. It also exhibits a vacuum when left over night. In all my years I've not seen this before. With the filler cap open a small seal is visible at the hinge end. It mates with a hole in the filler cap and is clearly part of the venting and I suspect EVAP circuit. I used a syringe placed on the seal and verified with VERY GENTLE pull push force that the path was blocked in both directions. Re performing the test with the tank raised...No blockage! Examining the vent pipe it can be seen it is pinched tightly in two places, this being caused by excessive pipe length in combination with resultant interference with a trim panel when the tank is in operational position. The vent pipe has a formed 90 deg elbow. I cut 10mm off the end of the pipe leaving the elbow intact. I re fitted the pipe such that the pre formed elbow was not strained., thereby eliminating chance of pinching. After re assembly, I verified success with the syringe test and now to re fuel and confirm success.
The bike is brand new so this was mr Honda's fault. Naughty Mr Honda!!
Thankyou to all for your help. It was indeed a pinched vent pipe.

[max]

Now you know why we call him LORD popgun, thanks mike, very perceptive and accurate, appreciate the feedback.