The correct washers from a BMW (cage) tuner site. They use the same part.

 

Nice pun.

 

Ordered the 25 pack from McMaster Carr website Sunday. They had a note saying the order would not be processed till after Memorial Day. $20.86 including taxes and shipping. About $.84 each. They arrived today.

Beemerboneyard filter wrench and filters ordered at the same time, still en route to USPS facility. Just saying... Only ordered filters from them to get the wrench order over the $20 minimum. :surprise:

 

The use of copper will merely pit the aluminum where the metals are in contact. The damage will be minimal, but why invite it?

 

Excellent point about the anodic/cathodic properties, especially in an area likely to see a lot of moisture (enabling/enhancing the corrosion as it's the medium). For our aluminum control section housing that I redesigned (JSOW missile), at first we had to coat with epoxy primer every stainless threaded insert (helicoil type) we used to prevent corrosion. We had a dedicated Engineer who did nothing but look at materials and corrosion issues. However, after new research came out in the mid '90's and was given to us by TI, it was found that, basically, the electrical potential of the dissimilar metals mattered. In other words, if the inserts were a small percentage of mass compared to the aluminum housing, the corrosion was not an issue. If it was a stainless casting with aluminum inserts (for the sake of argument) then the inserts would get eaten up in short order.

In this case, since the copper gasket is a very small mass compared to the engine castings, I'd say it's probably not an issue, especially since there's almost certainly a thin layer of oil between the 2 as a barrier. But since it has the "potential" (pun intended:laugh to cause light corrosion on the mating interface, why even chance it? The issue I'd be more worried about is that the torque value was designed based on how much pressure it would take to crush the softer aluminum, and with a copper washer of unknown value, you might end up getting either not enough or too much clamping force for a certain torque setting...possibly leading to stripping threads or the bolt falling out.

In short, me, I'd use stock washers and make sure they're oriented correctly and be worry-free...

 

I've got a bag of copper ones I use, I'll let you know if the engine explodes.

 

Oh, snap - read the replies too late.
Bought some Genuine BMW ones from a BMW car parts site.
Needed to buy a digital calliper and rear wipers for the wife's car, too.
The same part number for BMW cars... whodathunkit.

 

Just put some chewing gum around it. Works a treat.

 

I used high heat/pressure copper washers that I got on Amazon. Same size as OEM. They worked fine, changed them each oil change. If torqued properly and changed often they're fine. I still have a bag full of them. I don't remember the name, if you search for OEM size you will find them. They were much cheaper than OEM. For R1, motoD make alum one that are as good as OEM for one third of the price. Worth checking their catalog.

 

https://www.amazon.com/Crush-Washer...tive&ie=UTF8&qid=1526687620&sr=1-1&keywords=Crush+Washer+Oil+Drain+Plug+16+x+20

 

McMaster-Carr sells aluminum crush washers in the right dimensions for a much better price than the dealer. Just check their online catalog.

 

http://www.s1000rrforum.com/forum/1742738-post11.html

just ordered a pack of 25 16 x 19.9 mm aluminum crush washers from McMaster Carr.

https://www.mcmaster.com/#97725A850

 

This is the one I'm using: https://www.ascycles.com/Products/ProductID/2934/txtSearch/07119963252

 

Copper in direct contact with aluminum can damage the aluminum (aluminum is very anodic to copper).