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On a 2009 K1200lt,

In the Az summer she runs a little rough.

On my old VW fuel injection I could adjust the mix and get it to idle a little better in the heat.

Is there any way to do that to the K1200lt?

Maybe change spark plugs to a colder plug?

Or a adjustment screw in the fuel system on the bike?
 

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This sounds like the issue with high ambient temps affecting performance. Depending on what ECU is in your bike there may be a solution. On the 09, there is probably a small brown wire loop under the seat I believe on the right side. IF your bike has the proper ECU installed, then you can cut this wire and it will enable a secondary fuel map for non US bikes without cat converters and runs a richer mixture that usually cures the hesitation in higher temps. It has to be an ECU with the dual map though. A gs911 or the dealer MoDiTec readout can tell you what P/N is installed. I do not know what happens if you cut the wire with the wrong ECU but there are cautions about it.

Here is a thread to read and post #14 has links to more good information about the ECU P/N's and what you would need for that approach.

http://www.bmwlt.com/forums/k1200lt/155234-cat-code-plug.html

Another possibility is to unplug the air box temp sensor which also alters the mix. There are strong cautions about cutting the wire and also unplugging the sensor at the same time. It is a one or the other, not both. read up before you try either of these as you need more information to make a decision.

Lastly, there are chips available with alternate mappings also if you have the correct ECU. John Gemi (sp) is one who sells these chips on Ebay and swapping the chip might help your issue too although getting one of John's chips has been difficult as I think he is having health issues. Several options to evaluate if you really want to try and fix your issue.
 

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No, not really. The fuel injection system on the bike is controlled by the bike's Motronic Control Unit (the computer). You have an oxygen sensor attached to the exhaust system that "sniffs" the exhaust gases constantly and that info is used by the Motronic to adjust the air-to-fuel ratio being delivered to the cylinders. The A/F ratio is purposefully set at the factory to be on the lean side because this improves the EPA test results. Most bikes in most conditions do fine with the lean mix. But most bikes in most conditions would run better with a richer A/F ratio. The problem is, no matter what you do to make the A/F ratio richer, the O2 sensor will know and the Motronic will override.

One of the things that affects A/F ratios is air temperatures. If the bike is sucking in colder air, the computer will add more fuel to compensate for the increased density of the air. You still end up with the same A/F ratio. BUT . . . one of the things that some tuners have tried is to add an extra circuit to the temperature sensor to make it send false readings to the computer. Basically, to tell the Motronic that the ambient temperature is 20 degrees (F) colder than it really is. That's what the Boosterplug does, for instance. (https://www.boosterplug.com/shop/boosterplug-bmw-k1200lt-203p.html). The problem with these things (my opinion only) is the bike will run like it's being chased by the Devil on your first tank of gas, will run somewhat better on your 2nd tank of gas, and by the 3rd tank of gas the Motronic will have figgered out your Tom Foolery and adjusted things back to the baseline.

The next step is to try re-writing the factory programming in the Motronic. You will sometimes hear this referred to as changing "the map." In fact, sometimes even BMW will come out with a new map for a bike that's already on the road. Same goes for cars--I got a new map for my Jeep 6 months after I bought it (new) and the new map was a transformation. Just sayin'. For the LT, the only product that I know of that will re-write the Motronic map is John's Performance Chip. Does it work? I don't know. Are there drawbacks? I don't know. You should maybe start reading the threads here and decide for yourself. Here's one to get you started -- http://www.bmwlt.com/forums/k1200lt/176193-gemi-chip-install.html

Would everybody else now please chime in and correct any mis-info I've provided?
 
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This sounds like the issue with high ambient temps affecting performance. Depending on what ECU is in your bike there may be a solution. On the 09, there is probably a small brown wire loop under the seat I believe on the right side. IF your bike has the proper ECU installed, then you can cut this wire and it will enable a secondary fuel map for non US bikes without cat converters and runs a richer mixture that usually cures the hesitation in higher temps. It has to be an ECU with the dual map though. A gs911 or the dealer MoDiTec readout can tell you what P/N is installed. I do not know what happens if you cut the wire with the wrong ECU but there are cautions about it.
I think you are thinking about the 99 and 00 model LT's.
 

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I think you are thinking about the 99 and 00 model LT's.
Didn't the later models come with the brown wire? earlier models only had the cat code plug under the rear seat and no brown wire like mine. In any case, it does sound like the same issue with air temp over 80 and those were the potential solutions.
 

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Didn't the later models come with the brown wire? earlier models only had the cat code plug under the rear seat and no brown wire like mine. In any case, it does sound like the same issue with air temp over 80 and those were the potential solutions.
Only the 2002 - 2004 LT's had two maps with the brown wire.
 

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Only the 2002 - 2004 LT's had two maps with the brown wire.
Thanks for the clarification Dave. Is pulling the air box temp sensor still an option for Kevin?
 

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Okay, so I attempted to do one of these mods for my 05. According to this thread 02-04 is a brown wire cut? I have looked for a brown wire loop on my 05 and do not see it. Does that mean I am a Cat Plug unplugger from under the tour pack? It's always above 80 in South Texas. I have not owned my bike long. I am still getting to know her. I think I feel the lag from the timing retarder.

Thanks!
 

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No brown wire and no CAT code plug. Unplugging the air box temp sensor may help but I have not seen anyone report on the 05 with that.
 
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