Gas fuel cap suction normal?

[ekyang]

Hello everyone,

Is it normal for the R1150R to create a fair amount of suction in the gas tank where it's takes a little bit of extra effort to open up the fuel tank for refueling? I've been riding during summer weather here in South Carolina - but it seems like its almost too much suction to the point that my bike key pulls out of the gas tank flap keyhole unless I keep the key turned to "lock" it in place and give the key something extra to open with.

I did do a charcoal canister lobotomy recently but put it back on after hearing forum comments - and am now wondering if I reconnected the hoses correctly...

[CycleRob]

No, the suction is not normal. It indicates either the vent line is plugged or the canister is plugged up from the cap water drain line being connected to the canister. The bottom line on the canister should go down to the footpeg area and be open to drain.

Here's my copy-n-paste of my old post in a text file on how to determine if the 2 vent lines are hooked up right:

To check if your vent hoses are hooked up right you need to do a simple mouth-on-the-hose blow test. If you want an easy check without taking anything apart, put the bike on the centerstand for stability. Next, get a wet paper towel to clean off the 2 dirty drain hose ends hanging downward below the right footpeg. Standing on the right side of the bike, open the fuel filler cap, put a paper towel or rag in the filler pocket to prevent water or dirt from entering the gastank opening during this invasive test. Next, put your finger over the little hole at the 9 O'Clock position (front is 12 O'Clock) of the filler cap opening. Then kneel down and blow into one of the open ended hoses. Avoid all contact with the smallest diameter battery vent hose end (If you have one) as it may still have Sulfuric acid residues in it or oozing out it's tip, so be careful contacting its open end. As you blow into the other pencil sized hose, you should feel air coming out that 9 O'Clock hole up top where your finger is. If your drain hose has residual rainwater or fuel-up spilled fuel in it, that may also squirt out at your finger and hopefully be captured by the stuffed-in-the-opening papertowel. It may also be plugged up solid with rust and dirt. Then you should use a 3 foot length of weed wacker plastic trimmer line to poke out the bockage from the top down.
If you don't feel any air coming out the 9 O'Clock position of the fuel filler hole even though you are able to puff air into it, remove the towel/rag, fully close the fuelcap and blow into the larger hose again. You should also get the sensation of inflating a large balloon (the fuel tank!). After 1 to 3 quick "inflation" breaths, the compressed air should then blow back out the hose end at you confirming that your hoses were mixed up!

If you have it apart and can individually put your mouth on both of the plastic connector fittings attached to the fueltank vent hoses, you should be able to figure out that blowing air out the fuel filler 9 O'Clock hole means that hose goes downward to the street drain. The other hose, that tries to inflate the closed up fueltank, goes to the canister center port. The top canister port goes to the solenoid. The bottom cannister hose goes to the footpeg area street drain.

To avoid this mix-up . . . again, leave one of the plastic male connectors with the bike and the other male connector with the tank hose providing foolproof gender mating, like this;


EDIT: To update to a better, faster photo host.

[captaincable]

My tank had suction also due to the P.O. installing a back rest and removing the canister so it would fit, CycleRob re-routed the hoses as they were hooked up wrong and we are are going to put the canister under the gas tank (non abs) eventually.
Nice not having to pull so hard on the tank lid to open it, and I agree it should be on the bike, it has led to discoloration from gas dripping on F.D. the way it was routed. Good luck
Mike

[CycleRob]

I hope the detailed hose connection description makes "good luck" unnecessary!

When it comes to emission controls, I am one of their biggest OPPONENTS when they kill fuel efficiency or "drivability". The OilHead charcoal canister does none of those things. It is only guilty of being ugly and visible when the system cases are not there. Infrequently it can/will damage R1150RT fuel level sensors and cause other fuel tank anomalies when the vent/drain hoses are INCORRECTLY CONNECTED. Its normal canister purge function will slowly add its recovered/stored fuel tank vapors into the engine's intake manifold, and when it doesn't add any fuel vapors, the O2 sensor compensates for it. I had a functioning charcoal canister on my 2002 R1150R for all 63,874 miles over the 8 years it traveled. It even became partially liquid fuel soaked (twice) on refuel overfills, only to recover within a half hour and regain normal function. Even the BMW tech I spoke to that hates the charcoal canister admits that the (high quality) way it is constructed, the charcoal granules cannot possibly escape.

Besides the fuel vapor recovery and burn-while-you-ride system common to every gasoline powered car/truck since 1974, the one thing I valued the most was NO FUEL SMELLS when a hot engined bike was put in the garage and the door immediately closed. Just like the car and truck next to it . . . . No fuel smells. Don't you wonder why even car nuts (in spite of it being illegal) do not disable and remove the fuel tank charcoal canister systems? It is because they do no harm to performance and they perform a needed odor control function, which can be dangerous in confined, natural gas heated vehicle storage spaces.

[gregor]

Never been the norm in the UK to have these cannisters. And we do have ever increasing emissions requirements in UK and EU.
Over the decades we have been amazed at these emasculated, air pumped, California spec vehicles.
I understand your preferences for an odour free vehicle but it is not a real problem on this side of the pond. If fuel is overflowing enough to become a fire risk then a Buncefield repeat is due. (a recent large explosion and fire at a fuel depot).

Still enjoying the 800?