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Discussion Starter #1
Have 09 1200LT that tends to stall when bike is hot. (doesn't quit, but idles low/rough) When warm/hot the RPM will drop into the 500s as you come to a stop and then goes back to 900. Even though the idle comes back up I still have a hard time getting the RPMs back up when starting off again. Any ideas?
 

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FLYARNG said:
Have 09 1200LT that tends to stall when bike is hot. (doesn't quit, but idles low/rough) When warm/hot the RPM will drop into the 500s as you come to a stop and then goes back to 900. Even though the idle comes back up I still have a hard time getting the RPMs back up when starting off again. Any ideas?
I'd put the bike under a GS911 and see what it sez = expecially with regard to the exhaust oxygen sensor. Hopefully, you have some LTers in your area that are listed on the GS911 roster as having one for use. Good luck.
 

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FLYARNG said:
Have 09 1200LT that tends to stall when bike is hot. (doesn't quit, but idles low/rough) When warm/hot the RPM will drop into the 500s as you come to a stop and then goes back to 900. Even though the idle comes back up I still have a hard time getting the RPMs back up when starting off again. Any ideas?
I had the same problem on a K1100LT. Mine would die, if I waited a few seconds it would start up fine. This went on for a year till I noticed that it was temperature related. Turns out it was the engine temperature sensor telling the Motronics that the engine was cold. I changed the sensor and end of problem.

Robert
 

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My 08 LT started having the erratic idle just like your 09. After my 24,000 mile service I decided to sync the throttle bodies and found that my #3 throttle body was the culprit. Took me longer to fabricate an 8mm wrench then it did to sync the throttle bodies. Just another opinion to think about. Good luck!
FLYARNG said:
Have 09 1200LT that tends to stall when bike is hot. (doesn't quit, but idles low/rough) When warm/hot the RPM will drop into the 500s as you come to a stop and then goes back to 900. Even though the idle comes back up I still have a hard time getting the RPMs back up when starting off again. Any ideas?
 

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2005 K1200LT
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Try unplugging the temp sensor( the one at the back of the cylinder head) and see if it improves. This will fool the ECU into thinking it is hot and turn on the fans. If driveabilty improves that is the culprit .
 

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I have a similar problem, as the temp warms up it starts running rough and the tach starts and erratic dance. I might try changing the coolant sensor although my fans come on right when they are supposed to @ 105C.
 

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FLYARNG said:
Have 09 1200LT that tends to stall when bike is hot. (doesn't quit, but idles low/rough) When warm/hot the RPM will drop into the 500s as you come to a stop and then goes back to 900. Even though the idle comes back up I still have a hard time getting the RPMs back up when starting off again. Any ideas?
My 07 does this also and I have yet to find a solution. I bought a GS-911 and it shows nothing amiss. Fuel mileage is unchanged and fine (48 MPG average) so I don't think it is the O2 sensor. My leading suspicion is ethanol in the fuel and the problem began a couple of years ago and seemed to be pretty coincident with our last gas station switching to poisoned gas.

I may be able to test this theory now as one fairly local station (20 miles away) is now advertising that their 91 octane is ethanol free so I am going to try a few tankfuls of that.

Do you know if you are burning real gas or is it ethanol laced?
 

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Discussion Starter #9
FLYARNG said:
Have 09 1200LT that tends to stall when bike is hot. (doesn't quit, but idles low/rough) When warm/hot the RPM will drop into the 500s as you come to a stop and then goes back to 900. Even though the idle comes back up I still have a hard time getting the RPMs back up when starting off again. Any ideas?
And the answer is...........Bad O2 Sensor AND throttle position sensors needed reset.

Thanks for the help.

LJW
 

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Thanks for posting the successful results as that is what makes this site so helpful and a wealth of information.
 
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