K1200GT Gas Tank Vacuum

[17308]

After 17000 miles my bike starting running rough as though the fuel injection was either on or off between 2000-3000 rpm while riding through town. It runs smooth at hiway speeds but any change in throttle is abrupt, again like on or off. When I stopped to fill up the gas tank, I actually had to force open the gas cap due to a vacuum in the tank. The dealer can't find a problem. Now the bike stalls occasionally when coming to a stop, but starts up easily. Still drawing a vacuum in the tank which obviously isn't venting. Any ideas as to what might be causing the problem. I hate to leave for the National Rally with this hanging over my head.

[58058D]

Not sure why a dealer would not be able to find the problem as it sounds as simple as a plugged/pinched vent line. Sounds like it is time to follow the lines yourself and assure they are open. I have read other posts here where using air or a fine wire to run through your vents should take care of or at least indicate where the problems are. Possible the tank has been getting 'overfilled' and the vapor canister or the vent line to it is full of fuel? If you do a search for the subject you should be aboe to find other posts on clearing these vent lines.

[chuck_donahue]

Try running it with the cap open?
That is if there is no sensor, micro switch, or a dohicky thingamabob that won't let it run with the gas cap open. :dunno

[Gilly]

Wondering what year the GT is, previous brick style or new transverse engine.
Gilly

[17308]

[QUOTE=Gilly;475206]Wondering what year the GT is, previous brick style or new transverse engine.
[/QUGillyOT

It's a 2007 with the new transverse engine

[jcpuckett]

After 17000 miles my bike starting running rough as though the fuel injection was either on or off between 2000-3000 rpm while riding through town. It runs smooth at hiway speeds but any change in throttle is abrupt, again like on or off. When I stopped to fill up the gas tank, I actually had to force open the gas cap due to a vacuum in the tank. The dealer can't find a problem. Now the bike stalls occasionally when coming to a stop, but starts up easily. Still drawing a vacuum in the tank which obviously isn't venting. Any ideas as to what might be causing the problem. I hate to leave for the National Rally with this hanging over my head.

The activated carbon canister is probably plugged or the rubber vent hose plugged. If an insect crawls up the vent tube and dies, that will do it. Quick test - run with your fill cap open. I did that on my RT to prove that vacuum was causing my intermittent fuel starvation problem.

[58058D]

It's a 2007 with the new transverse engine[/QUOTE]

Might get better answers over at the Wedge heading?

[Gilly]

'zactly what I was getting at. Mod???
Gilly

[gfmecm]

The activated carbon canister is probably plugged or the rubber vent hose plugged. If an insect crawls up the vent tube and dies, that will do it. Quick test - run with your fill cap open. I did that on my RT to prove that vacuum was causing my intermittent fuel starvation problem.

Another option is to pull the vent hose off the canister. I did that on my RS when I had a similar problem. That should provide a clear vent to the tank if the canister is clogged. Mine was rusted. I'm not sure how hard the canister is to get to on the GT, but if you can pull off the hoses and check the condition of the canister connections, that should give you another clue. I ended up doing a "canisterectomy" rather than replacing the canister. I don't know if that is an option for you. Good Luck.

[deilenberger]

Moved to wedge forum..

[free2ride]

Is there a written procedure somewhere for doing a canisterectomy? I performed one on my LT but had good written instructions.

[gregfuess]

My '08 12S started doing this on hot days after long rides. Totally die at low rpms. Options are to keep the rev's above ~2,500 or be patient. It restarts almost immediately, but has to cool wa-ay down to idle properly. Just went through the 18k miles service, so hopefully that will cure this issue?

Greg

[cjack]

My '08 12S started doing this on hot days after long rides. Totally die at low rpms. Options are to keep the rev's above ~2,500 or be patient. It restarts almost immediately, but has to cool wa-ay down to idle properly. Just went through the 18k miles service, so hopefully that will cure this issue?

Greg
If you don't have vacuum building up in the tank, it's probably not your answer.
There's a bulletin out meant for the 1300s but may be your issue as well. Some have had deposits build up in the throttle bodies preventing proper flow. Cleaning fixes them. There has also been a 13S with perfectly clean TBs, but resetting with the dealer's computer fixed the problem.

[dwestly]

The throttle body build-up is a separate issue and causes stalling when the throttle is shut off but doesn't impact smooth running between 2k-3k rpm. It can also cause a delay in throttle response at higher rpm. I had both these issues with my 09 13GT, but a trip to the dealer and throttle body cleaning cured both problems. BMW has now issued an interim fix to the throttle body issue, which consists of interval usage of fuel additive to keep the throttle bodies clean, until they can do a final fix. According to at least one major m/c magazine, the K1300 throttle body fix is currently BMW's highest priority and a final fix is forthcoming. (only relaying what I read on this last...)

[cardinal51]

Did anyone find the problem here? I just got back from a trip to New England and my 1100 GS did the same thing. I was having a problem on opening the tank when stopping to fill up. The bike ran fine with no problems. Then I noticed the vacumn actuall sucking in both sodes of the tank. A small 6 inch dimple on the roght side and the whle left side of the tank. Finished the trip leaving the tank open under the tank bag. Now I have to figure what may be wrong and how to get the dents out of the tank. Any thoughts would be appreciated.

[cjack]

Did anyone find the problem here? I just got back from a trip to New England and my 1100 GS did the same thing. I was having a problem on opening the tank when stopping to fill up. The bike ran fine with no problems. Then I noticed the vacumn actuall sucking in both sodes of the tank. A small 6 inch dimple on the roght side and the whle left side of the tank. Finished the trip leaving the tank open under the tank bag. Now I have to figure what may be wrong and how to get the dents out of the tank. Any thoughts would be appreciated.

Check the hose from the vent on the tank to the canister...and the canister. Sometimes the canister fills with gas and doesn't vent the tank.