twin spark plug part numbers
 

for those curious:

12127653771 larger center location plug-NGK $5.95
12127671302 smaller bottom location plug-Bosch $5.99

they both have two leads. meant to write down the actual manufacturer number for those to cross-reference. promise to do that later tonight. all i have in front of me is a sheet with bmw part #'s.

repoe3

Greetings Repoe,

Thanks!

Robert Foster

been lazy but finally posting the manufacturer's number, so here they are:

12127653771 larger center location plug-NGK $5.95
BKR7EKC

12127671302 smaller bottom location plug-Bosch $5.99
YR6LDE

now cross reference your hearts out...

repoe3

What do you mean by "larger center location" and "smaller bottom location" plugs? I thought there were just two spark plugs and they were both located on the same spot of each cylinder and were the same size? I know I must be missing something so please forgive the stupid question.

Speaking of which, is there a list of factory-equivilants plugs that work in the R1100S? I assume anything you get at Kragen, etc are cheaper them the stock BMW plugs and work just as well.

Thanks!

the center, or primary plug, like all previous oilheads, is a physically larger plug than the lower one added to the twinspark oilheads.

you will go round and round looking for equals. there are some to be had for the primary plug, but i have had zero luck with the lower plug.

i gave up and order or pick the bmw branded NGK and bosch plugs.

repoe3

I'm sorry - I must totally be missing something. I thought there were just two cylinders on the R1100S, hence two sparkplugs. Both of which are located in the same location? Is there a lower and upper one I am not seeing or something? And I would think both plugs would be the same size?

The later models are different, and have 2 plugs per cylinder.

not to mention, lots of twins have two spark plugs...ducati and aprilia to name two semi-well-known brands.

it varied by model, but you can clearly see the difference as the coil cover says "twinspark" and is shaped differently. there will be a second plug under a plastic cover at the bottom of the head. man, the debates this created when it first happened. donuts and squish.

repoe3

OK. So on the 1999 R1100S, each cylinder has two spark plugs? I thought the plugs were located on the sides of the cylinders - not one on the top and one on the bottom? So, are the two plugs sitting side by side?

99-2002 have 1 plug per cylinder. 2003- have 2 per cylinder...

Ah ha! Now things are becoming clearer! So, as I read through all the threads it looks like any of these plugs will work in my 1999 R1100S:

NGK BKR7EKC
Autolite 3923
Bosch +4 4417
Bosch FR6LDC

Yes?

looks like it.

repoe3