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Quick question...

Wires removed. I've check the Ohms from End to End. Factory orig. wire at plug end is stamped 5K Ohms.
Does that mean that end to end resistance should be *around* 5K Ohms?

My wires, which look good: no breaks, chaffing, cracks etc. Pliable, not brittle:
#1 - 6.59
#2 - 6.51
#3 - 7.03
#4 - 6.63

A little history... EIGHT! years ago bike was running crappy after a dealer service. No smootheness at steady RPM. Stumbling, decreased gas mileage, reduced power until giving it increased throttle... then spitting, slight hesitation again until increased throttle! At any steady RPM: crappy running. I live in Miami, that was the Summer of 2009. It was H~O~T so I garaged bike and didn't ride it becaue the performance wasn't enjoyable. Not thinking it would be an extended layup. I never put any stabilizer in the tank...
Life events got in the way...
A coupla years later... I noticed familiar "stink" at the gas cap and despite new battery and gas. Bike didn't start: Fuel Pump eff'd.
More years...
Tore bike down saw that tank breather & overflow lines disconnected at right side of tank. I figured THAT was the reason for the crappy running that dealer forgot to connect them!?
More years... bike SAT covered outside in front walkway exposed to ALL the elements and CRITTERS for perhaps a year.
Many deal snail shells on top of engine and all inside and peanut shells presumable mice &/or squirrels. No evidence of wire chewing... YET! Factory electrical tape wrapping fine wires disintegrating all over bike however there no apparent wire intrusion and appears intact.

Since Feb. 2017 or 4 months ago I started the resurrection process: new fuel pump, filter, battery (Odessy), ALL fluids. Some setbacks overcame.
First shake-down ride was 2 Saturdays ago... bike still ran crappy as thought it was the same EIGHT years ago after dealer service. Ugh!

Bought new spark plus as old oem Bosch's had 13K miles on them. Replacing them with the NGK Iridiums recommended here. While prepping to replace plugs, I decided to check spark plug wires and their resistance as I read many threads here discussing replacements.

So, are my wires the cause of the crappy running as they are "over-resisted" or do my Ohm readings have nothing to do with the 5K Ohms stamped on the plug end of the wires?

TIA,

TERRY-Miami
2002 K1200LTC 30K miles in the process of Resurrection!
 

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Quick question...

Wires removed. I've check the Ohms from End to End. Factory orig. wire at plug end is stamped 5K Ohms.
Does that mean that end to end resistance should be *around* 5K Ohms?

My wires, which look good: no breaks, chaffing, cracks etc. Pliable, not brittle:
#1 - 6.59
#2 - 6.51
#3 - 7.03
#4 - 6.63

A little history... EIGHT! years ago bike was running crappy after a dealer service. No smootheness at steady RPM. Stumbling, decreased gas mileage, reduced power until giving it increased throttle... then spitting, slight hesitation again until increased throttle! At any steady RPM: crappy running. I live in Miami, that was the Summer of 2009. It was H~O~T so I garaged bike and didn't ride it becaue the performance wasn't enjoyable. Not thinking it would be an extended layup. I never put any stabilizer in the tank...
Life events got in the way...
A coupla years later... I noticed familiar "stink" at the gas cap and despite new battery and gas. Bike didn't start: Fuel Pump eff'd.
More years...
Tore bike down saw that tank breather & overflow lines disconnected at right side of tank. I figured THAT was the reason for the crappy running that dealer forgot to connect them!?
More years... bike SAT covered outside in front walkway exposed to ALL the elements and CRITTERS for perhaps a year.
Many deal snail shells on top of engine and all inside and peanut shells presumable mice &/or squirrels. No evidence of wire chewing... YET! Factory electrical tape wrapping fine wires disintegrating all over bike however there no apparent wire intrusion and appears intact.

Since Feb. 2017 or 4 months ago I started the resurrection process: new fuel pump, filter, battery (Odessy), ALL fluids. Some setbacks overcame.
First shake-down ride was 2 Saturdays ago... bike still ran crappy as thought it was the same EIGHT years ago after dealer service. Ugh!

Bought new spark plus as old oem Bosch's had 13K miles on them. Replacing them with the NGK Iridiums recommended here. While prepping to replace plugs, I decided to check spark plug wires and their resistance as I read many threads here discussing replacements.

So, are my wires the cause of the crappy running as they are "over-resisted" or do my Ohm readings have nothing to do with the 5K Ohms stamped on the plug end of the wires?

TIA,

TERRY-Miami
2002 K1200LTC 30K miles in the process of Resurrection!
Well, a lot of things could cause this on an LT. If you don't have a service manual, Clymer or BMW REProm, consider getting one and a GS-911 can be worth it's weight in gold for problems like this.

I don't think the unhooked fuel lines would affect this. They just let air into the tank and control the direction of overflowed fuel. Other than making a mess if you overfill your tank, they shouldn't affect anything.

I tend to not suspect ignition issues either as they tend to be less RPM dependent. A bad plug or wire will generally act up whether at steady rpm and throttle or at wide open throttle and high rpm.

This sounds like a fuel issue. Did you replace all the in tank lines when you replaced the fuel pump? Particularly, the U-shaped hose?

It would be nice to have GS-911 data on the lambda sensor and the throttle position sensor.

I am not familiar with the models older than my 07, but I believe the older bikes had a brown wire that could be cut to switch to a different fuel map. What I can't remember is if this was better or worse for hot weather. Also, I believe you could disconnect the temp sensor on the airbox, but not in addition to cutting the wire.

Since it began after a dealer service and you found one mistake already, I would start checking connections to see if a sensor was left unplugged. Or maybe a vacuum line on the TBI. It sounds like your issue is worse under high vacuum operation (part throttle), which can point to a vacuum leak. Although, that often also affects idle and I didn't see any mention of idle issues in your post.

Sitting with gas that has gone bad would also risk gumming the injectors. Although, that wouldn't have been an issue when you first saw the problem years ago.
 

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Quick question...

Wires removed. I've check the Ohms from End to End. Factory orig. wire at plug end is stamped 5K Ohms.
Does that mean that end to end resistance should be *around* 5K Ohms?

My wires, which look good: no breaks, chaffing, cracks etc. Pliable, not brittle:
#1 - 6.59
#2 - 6.51
#3 - 7.03
#4 - 6.63

A little history... EIGHT! years ago bike was running crappy after a dealer service. No smootheness at steady RPM. Stumbling, decreased gas mileage, reduced power until giving it increased throttle... then spitting, slight hesitation again until increased throttle! At any steady RPM: crappy running. I live in Miami, that was the Summer of 2009. It was H~O~T so I garaged bike and didn't ride it becaue the performance wasn't enjoyable. Not thinking it would be an extended layup. I never put any stabilizer in the tank...
Life events got in the way...
A coupla years later... I noticed familiar "stink" at the gas cap and despite new battery and gas. Bike didn't start: Fuel Pump eff'd.
More years...
Tore bike down saw that tank breather & overflow lines disconnected at right side of tank. I figured THAT was the reason for the crappy running that dealer forgot to connect them!?
More years... bike SAT covered outside in front walkway exposed to ALL the elements and CRITTERS for perhaps a year.
Many deal snail shells on top of engine and all inside and peanut shells presumable mice &/or squirrels. No evidence of wire chewing... YET! Factory electrical tape wrapping fine wires disintegrating all over bike however there no apparent wire intrusion and appears intact.

Since Feb. 2017 or 4 months ago I started the resurrection process: new fuel pump, filter, battery (Odessy), ALL fluids. Some setbacks overcame.
First shake-down ride was 2 Saturdays ago... bike still ran crappy as thought it was the same EIGHT years ago after dealer service. Ugh!

Bought new spark plus as old oem Bosch's had 13K miles on them. Replacing them with the NGK Iridiums recommended here. While prepping to replace plugs, I decided to check spark plug wires and their resistance as I read many threads here discussing replacements.

So, are my wires the cause of the crappy running as they are "over-resisted" or do my Ohm readings have nothing to do with the 5K Ohms stamped on the plug end of the wires?

TIA,

TERRY-Miami
2002 K1200LTC 30K miles in the process of Resurrection!
For the resistance specs, to the best of my knowledge, all K1200LT and K1200RS came with same type of Spark-plug wires and Caps from factory (although BMW might have used 2 suppliers at a certain point: BERU or BREMI).

As shown in attached photos, the CAPS have a fixed 5K Ohms resistance and Wires have a 1K Ohms resistance based on a fixed length specs (unknown if per feet): hence the sum of both will always be just above 6k Ohms from end-to-end (as all 4 cylinders do not have same length of wires). I would not worry too much as long as you do not get above 7K Ohms based on instrument and measurement errors.... ALSO are you measuring brand new wires or old ones??

AS-FAR-AS engine running bad, I would say there are too many variables in your situation (based on your post) to troubleshoot at a distance.
Too many possible causes, but history shows that these are most common to attack first fro old K1200LT that had lacked maintenance AND usage:

(1) air-leak from intake rubbers (manifolds rubber, vacuum hoses, crankcase breather 4-into-1 hose)

(2) cracked or damaged hoses inside fuel tank before and after fuel-filter.

(3) blocked fuel-filter (constant 50 PSI fuel pressure is critical to function properly)

(4) partially blocked fuel tank vent hoses (either en-route to charcoal canister OR from inside of charcoal canister). NOTE this applies to USA specs K1200 only,

(5) Incorrect free play at throttle cables. Must rest at idle stop when starting and no need to touch / increase throttle during starting phase. Remove Motronic EFI fuse for 20 minutes (ignition OFF) to reset all parameters in case EFI is confused by previous idle throttle position.
 

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The brown wire fix Matt ( Voyager) is referring to is poor running when it is over 80 degrees and on those properly equipped, cutting the brown wire ( or removing the yellow cat code plug under the passenger seat ) enabled a different fuel map and usually fixed that issue.

The 5K is a resistor in the head of the spark plug wires. I am not sure that the readings you have would consider calling a wire bad or not. The most common issue with the plug wires is a breakdown of the insulation and they arc to ground rather than across the gap and that causes very poor running depending on how many are doing that. You can open up the wire cavity and look at it in the dark for arcing. There are also tel tail signs if white dots where the arcing may have been occurring. EME sells a good NGK set much cheaper than OEM wires. Link below. I am running them with no issues.

EnDuraLast - BMW K1200 Ignition Cables ; 12 12 1 464 934, 12 12 1 464 935, 12 12 1 464 936, 12 12 2 305 044

Also mentioned is the internal tank fuel lines. If leaking, the fuel pressure can be low and cause poor performance. If they burst or pop off, the bike obviously will not run at all.

The disconnected breather and overflow lines may have been an attempt at the canisterectomy improperly implemented. Should not cause any poor running unless the purge valve is disconnected on the left side in front of the fuel rail.

A GS911 is very usefull so if you can borrow one, it can point to or eliminate many things but the fuel supply system is not monitored on the LT.

There are some things you can check, the wires glowing ( arcing) in the dark, with the top Tupperware removed, you can pull the fuel sensor tube and inspect the internal fuel lines. If you do start the bike with the tube removed, be aware that if the lines are leaking, you may get squirted in the face with gas so be careful looking in while priming or running. Check the plug on the air temp sensor on the front left of the air box. Someone may have pulled that as it is an alternate fix to the brown wire. Also may run poorly if that sensor is bad. That would show up with a GS911. There may be some resistance tests you can run on it. I don't have those values though.

EDIT:
And as Sailor said who posted just before I did, vacuum leaks on the rubbers or between the TB and block go along with a leaky purge valve hose. The purge valve can be blocked off entirely and that is an important part of the canisterectomy.
 
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