BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

As everyone here probably knows, or may find out the hard way, the Auto-Lite 4164’s are a replacement for the bottom plugs on the twin-spark models. However, they won’t fit in the standard BMW plug wrench and to make matters worse, a standard 11/16” deep socket that fits the plug will not fit up into the plug well of the engine.

One solution would be to buy a thin-walled socket, but I found them to cost $20.00 or more and that seemed a little steep to me. So, as I stated at the end of another post, in a fit of rage I went to the nearest auto parts store and bought a cheap 11/16” deep socket and ground it down on my bench grinder till it fit. After all, I would only be out $5.00 if it didn’t work.

It’s not pretty, but it worked:


Up close:


As you can see it was pretty crude. And due to the out of roundness I thought at the time, it was sticking inside the well a bit. But, I didn’t want to grind on it anymore because it was starting to get pretty thin.

Well, the possibility of having a socket get stuck in the engine wasn’t sitting well with me so just before Christmas I picked up another socket. I took it to a friend who’s in charge of the Tool & Die Dept. where I work, along with my crude attempt & the BMW tool, and explained what I needed. In about 10 minutes he showed up in my cube with this “BMW Quality” version:


Up close:


Holding my crude version, He said: “You ground this down on a bench grinder?”
I said: “Yeah, why?
He said: “I measured it and it’s nearly perfectly round! You may have a second calling!”

There you have it, my simple low-cost solution to the Auto-Lite 4164 problem! Well, as long as your pretty good with a bench grinder, have a lathe, or a Tool & Die guy handy anyway.

That's a nice solution...

I was wondering if I could get the measurements, outside diameter and how far down/up the socket you ground for clearance.

Thanks
John C.

No problem:

1- Duracraft Pro 11/16" CR-V, 3" long, 1/2" drive, Deep Socket (appx $5.00)

Modification Dimensions: Turned down to a diameter of .850" for 1" from the socket end.


FYI: The one I ground down measures .858" dia. at it's widest and was only ground down for appx. 5/8". And, the BMW socket measures .849 dia. at it's widest and is fluted for about 5/8". I had them turn an inch off in case I needed it for something else. Of course when that happens, I'll need a different size

Thanks Mark,
I'll see about getting one of these modified by the local machine shop. (They do good work and charge next to nothing.)

Thanks again!
JC

Very nice and thanks for sharing. Probably a stupid question but, is this problem just for the twin spark Bottom plugs? I have a single spark and have not changed my plugs myself yet. I didn't know if I would need to do the same mod or not.

Buckster,

This is specifically for using Auto-Lite 4164's as the replacements for the bottom plugs on twin spark models. The 4164's are available at most local auto parts stores where the Bosch YR6LDE replacements had to be ordered.

The plug wrench that came in the BMW tool kit will work on the top plugs. In fact it's required because of how deep they are in the cylinder.

Buckster,

This is specifically for using Auto-Lite 4164's as the replacements for the bottom plugs on twin spark models. The 4164's are available at most local auto parts stores where the Bosch YR6LDE replacements had to be ordered.

The plug wrench that came in the BMW tool kit will work on the top plugs. In fact it's required because of how deep they are in the cylinder.

Good tip, Mark. Wish I had thought of something like that last spring when I found out that tightening the Autloite secondary plug with vice grips (couldn't find a workable socket to fit) resulted in this:



Pretty nasty, eh? The plug loosened up and eventually fell out before I had a chance to tighten it up properly. Here's some more damage:



Yup, even burned up the engine guards:




Lesson learned (the hard way): get a proper wrench and tighten that bugger! Now I've got a stripped secondary plug hole, and though the wire has been "repaired" by a BMW shop, I won't feel right till it's replaced. And who knows what other damage I might've done - won't know that until the head is removed and I can see the valves and piston crown. Wish me luck ...

Here is what I think is a better alternative to using the 4164 Autolites for the secondary plug. I have been running the 3923's as primary's with good results for the past year. Just installed my second set last week. I seriously considered using the 4164's and bought a set but the issue of the plug wrench stopped me. I considered having one turned down but thought that not a good alternative just to use the 4164.

NGK's website: http://www.ngksparkplugs.com/ Provides some useful information concerning plugs

The NGK DCPR6E is the NGK recommended plug for the secondary in the 1150. Fits the BMW plug wrench just like the 3923 and is $2.29 each at Advance Auto. Their part number is 3481.

I installed a set of secondary's today and ran probably 200 miles. Ran fine. I could tell no difference between the Bosch oem's and the NGK's in terms of starting and performance. If you want to go a step higher and get platinum tipped you'll pay a buck or so more per plug. (Advance Auto) Still not a bad deal. The 3923's and the DCPR6E's seem to me to be a very good and inexpensive alternative for spark plugs for our machines. By the way NGK lists the plug gap at .032 (Primary) and .028 (secondary) and those numbers are for our bikes specifically. fwiw---I had already set mine at .034 on both and it ran fine. I may change them to the above gap numbers and check the difference.

Wayne

Cool!

Thanks for all the info Wayne!

I'll more than likely order a set of DCPR6E's next time I change them. No one had them in stock locally. Nearest "Adv. Auto" is an hour away. The pains of living in "Corn County IL"

Mark---I bet you could order online from their website--maybe get two or three sets to make it worth the shipping.

Wayne

thanks for the info. I found an NGK solution also. Found some at NAPA, but there, whichever ones I got, were $20 for the pair (platinum). That was over 12k miles ago and when last checked they were fine looking. But $3 a piece is better.

John