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arcing between spark plug lead and valve cover

Detroit Kim

New member
Got stranded last night on the way home from work.
My 1150RT started missing, then was only firing on the left cylinder.
I heard a cracking from the right plug area and could see arcing from the lead to the cover.
I switched the plugs left to right to check if the plug had failed, but the right cylinder lead still shorts.
The lead looks perfectly healthy with no splits or cracks.
Has anyone elase had this issue.
Hopefully all thats needed is a new lead.
 
Does that bike have dual spark plugs and stick coils on the ends of the wires? I've heard of stick coils failing and arcing to the heads also.

If it's just bad wires Euromotoelectrics has very high quality replacements for much less than BMW.
 
Does that bike have dual spark plugs and stick coils on the ends of the wires? I've heard of stick coils failing and arcing to the heads also.

If it's just bad wires Euromotoelectrics has very high quality replacements for much less than BMW.

Single plugs.
Thanks for the reply and I'll check out the non BMW plug lead link.
So the coils are in the lead heads ?
 
I've seen this on an 1100 also; the owner had actually wrapped a band-aid over it in an attempt to reduce the arcing... it was all he had!

There was a hardware store nearby, so we wrapped it all up with black tape; got him home.

If you have two plugs per cylinder, yes the "stick" coil is right there on the end of the cable. They are a bit fragile, so it's quite worthwhile to buy an all-metal puller instead of using the cheapie P.O.S. plastic puller from the toolkit. If you have one plug per, then the coil is under the front of the gas tank.
 

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Whats involved in taking the tank off or can you just lift clear enough to replace leads. (1150RT).
I removed the rear bolt from the RHS, but didn't want to start yanking on it before I new it would be safe.
 
'Taint no lifting it just to clear; it's tedious but not difficult. If it's like my '04:
remove bottom cowling, seat, black sidepanels
remove both mirrors (knock off)
remove both body sidepanels
remove glovebox (some hidden screws, one inside top rear and one outside bottom front; also helps to remove air intake snorkels)
remove big tank screw from bottom right rear (don't drop nut or washers, note bushings)
unplug 4-conductor connector (pump etc.) @ bottom right of tank
Drain tank if you haven't already; gas is about 6 pounds per gallon and the tank is clumsy to handle
disconnect two fuel lines (now is the time to install Quick Disconnects if you don't have them already)
gently lift and pull tank to rear to clear
I've probably missed a few details...
 
'Taint no lifting it just to clear; it's tedious but not difficult. If it's like my '04:
remove bottom cowling, seat, black sidepanels
remove both mirrors (knock off)
remove both body sidepanels
remove glovebox (some hidden screws, one inside top rear and one outside bottom front; also helps to remove air intake snorkels)
remove big tank screw from bottom right rear (don't drop nut or washers, note bushings)
unplug 4-conductor connector (pump etc.) @ bottom right of tank
Drain tank if you haven't already; gas is about 6 pounds per gallon and the tank is clumsy to handle
disconnect two fuel lines (now is the time to install Quick Disconnects if you don't have them already)
gently lift and pull tank to rear to clear
I've probably missed a few details...

I quite easily managed to lift the tank away high enough to get god access to the coil pack to replace the leads. Ended up only being a 1/2 hour job. I've got taking the tupperware off to a fine art now.
Thanks for the link to after market suppliers of the leads. Saved me $$$$.
Its weired how leads just suddenly go from working 100% to complete failure. I did try to wrap the offending lead in electrical tape, but the arcing still took place
 
I ordered a set for my Roadster, too!

BMW-WSR641OE Original Equipment Style Spark Plug Wire Set - BMW R Oilhead; 12 12 1 342 641 / EnDuraLast
1 $59.00

Subtotal: $59.00
Tax: $0.00
Shipping & Handling Cost: $6.20
Grand Total: $65.20

LINK>>>euromotoelectrics.com
 
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The caps at the coil and spark plug ends usually have markings molded into the rubber.

Are these Bosch or Beru items and what numbers are on them if anyone has a set out in the open.

Also, how to the wires attach to the caps? Do they use a threaded brass end on the wires?
 
The caps at the coil and spark plug ends usually have markings molded into the rubber.

Are these Bosch or Beru items and what numbers are on them if anyone has a set out in the open.

Also, how to the wires attach to the caps? Do they use a threaded brass end on the wires?

No marking's found.
Wires are one piece. Like my 1995 Factory wires.













Part #: BMW-WSR641OE

*Original Equipment Style Plug Wire Set ( x 2 wires) for BMW R850, R1100, R1150, R1200 thru 2006.
*OE Style boot allows use of BMW spark plug removal tool (Part # 12 12 2 306 064)

*Assembled with 7mm silicone wire, stud connected silicone boots, and internal brass tubing for positive spark plug terminal nut support. Includes nylon anti-chaffing sheath jacket over the full length of the cable.
*Less than 50% the price of 2 wires from BMW Dealer !
*Silicone withstand temperatures up to 1200?F / 650?C
 
No marking's found.
Wires are one piece. Like my 1995 Factory wires.

First, a big thanks for taking the time to post pics of the new cables.

What I was looking for were markings on the original BMW ignition cables. I would guess that you might find Bosch or Beru marked on them along with some numbers.
 
And the point your trying to make is....?

First, a big thanks for taking the time to post pics of the new cables.

What I was looking for were markings on the original BMW ignition cables. I would guess that you might find Bosch or Beru marked on them along with some numbers.

Yes, the O.E.M. have numbers and Beru on them. What is the point your trying to make?
 
Yes, the O.E.M. have numbers and Beru on them. What is the point your trying to make?

I'd just like to know what the part numbers are. I can then find out if the cables are attached the same way as the Beru cables I made for my Porsche. And if so, I can make at least two of them for my dual-spark R1150 GS if needed.
 
Part #: BMW-WSR641OE

*Original Equipment Style Plug Wire Set ( x 2 wires) for BMW R850, R1100, R1150, R1200 thru 2006.
*OE Style boot allows use of BMW spark plug removal tool (Part # 12 12 2 306 064)

*Assembled with 7mm silicone wire, stud connected silicone boots, and internal brass tubing for positive spark plug terminal nut support. Includes nylon anti-chaffing sheath jacket over the full length of the cable.
*Less than 50% the price of 2 wires from BMW Dealer !
*Silicone withstand temperatures up to 1200?F / 650?C
 
I'm a little late to the dance, but I would like to also thank all those who gave advise, I did some damage to the spark plug end on the left side trying to get it disconnected from the spark plug, although the damage is slight, I order a set of wires from the Beemerboneyard, Question, someone mentioned a metal plug wire removal tool, anyone know where this can be purchased? Also anyone know the life of the plug wires? the MC is a 2002 R1150R, with 50k. Thanks in advance, Den
 
These are solid wire not resistor wire,. Most bikes will go the scrapper with the original cables. They do not wear out. Some do fail, and fail is different than wear. A match head sized dot of dielectric silicone in the end, keeps the boot from sticking to the plug. The removal is easy enough to avoid damage.

Rod
 
These are solid wire not resistor wire,. Most bikes will go the scrapper with the original cables. They do not wear out. Some do fail, and fail is different than wear. A match head sized dot of dielectric silicone in the end, keeps the boot from sticking to the plug. The removal is easy enough to avoid damage.

Rod

Agreed, 251,000 km on my original '00 GS wires.
Always use dielectric grease on the plug end.
 
Thanks again!, I have changed the plugs several times & never a problem removing the plug wire, but this time it was "stuck" & in my zeal I caused some damage, I have dielectric on the shelf,& will be using it in the future, I appreciate the advise! msn
 
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