Google I love you.

http://www.bavauto.com/se1.asp?dept_id=51

Several suppliers on flea-bay too. Ok, no need to panic. 

There are other ways to make the stock cap a locking cap.  A bar or a pin in the right place, maybe brazed on, or mounted with those screws with one-way heads.

11 minutes ago, Zed Head said:

There are other ways to make the stock cap a locking cap.  A bar or a pin in the right place, maybe brazed on, or mounted with those screws with one-way heads.

Why not just pop rivet one these over the fuel door? By a good study Master padlock and your set.

The fancy chrome hood lock pins probably looked like that when they started but now people put them on for show.

I think that you could get it done under the door.  Not visible.  Just an option.  A ready-made cap with a key would be nice, but apparently they're not available.

I suppose you all would go gaga if I welded a tiny bracket with a hole on the back of the BMW gas cap to provide a connection for that all-important chain, wouldn't ya?

Plainly I need to sell a package of modified locking gas cap, and modified and fitted mounting ring. Maybe even a new rubber flap and bolts?. Naw that's just getting carried away, ain't it?

2 hours ago, zKars said:

OMG Steve, ROFL,  I'm just recovering now about the Chevy Chase scene... Oh my aching sides  I've learned my lesson with you guys for sure.

Ok, after staring at the ring and BMW cap for 10 minutes, the solution is really pretty simple.

You just need a stop block at the right spot. Pictures are worth 1176 words..

First weld in a scrap of metal, here. 

Put BMW cap in, twist to stop position, turn key to lock, lock tab now protruding and trapped behind welded in tab. 

A pic with the key in open position, free to turn CCW to unlock.

Had to use the rubber gasket from the stock cap, which is thicker. The tabs on the BMW cap are angled away from the body and will leave the cap loose if you don't have enough gasket thickness. Stock is about .012, BMW was only .08 ish

Another issue is the cap OD verses the ID of the mounting ring. Dang tight fit. I just did a little hammer tap tap around the inside to roll the lip just a smig and it slips in easy.

Ok who wants a modified mounting ring? Choice of powder coat, CAD plated, spray paint or sand blasted bare DIY.

This is similar to what I had in my mind's eye. I was thinking that the block could go into the notch on the ring.

Just now, zKars said:

OMG Steve, ROFL,  I'm just recovering now about the Chevy Chase scene... Oh my aching sides  I've learned my lesson with you guys for sure.

Ok, after staring at the ring and BMW cap for 10 minutes, the solution is really pretty simple.

You just need a stop block at the right spot. Pictures are worth 1176 words..

First weld in a scrap of metal, here. 

Put BMW cap in, twist to stop position, turn key to lock, lock tab now protruding and trapped behind welded in tab. 

A pic with the key in open position, free to turn CCW to unlock.

Had to use the rubber gasket from the stock cap, which is thicker. The tabs on the BMW cap are angled away from the body and will leave the cap loose if you don't have enough gasket thickness. Stock is about .012, BMW was only .08 ish

Another issue is the cap OD verses the ID of the mounting ring. Dang tight fit. I just did a little hammer tap tap around the inside to roll the lip just a smig and it slips in easy.

Ok who wants a modified mounting ring? Choice of powder coat, CAD plated, spray paint or sand blasted bare DIY.

I do !!!   How much are you selling it for???   Whichever "coat" looks best with a Red Z.

Thanks for figuring it out!

Jai 

I have a simplified solution now. No more extra piece of steel to weld in, just a weld bead on the side that sticks out just the right amount. Also discovered that a stock cap's tangs wouldn't clear the initial extra bit, but the weld bead works just fine with either. 

 

 

Jim,

That's looks good. If Jai wants yellow zinc I would take a stab at it with my Caswell setup for free. Just remember you get what you pay for...

Charles that's great idea. Thanks for the free plating offer.  Do you have a way to weld that bead before you do the plating? Doesn't make $$ sense for me to ship to you then you to her. Maybe just get Jai's and do the mod for her.. You two are on the same side of the continent!. In the meantime Jai can order up a cap then by the time you're done, she'll have all the pieces. 

I'll send my modded one to you first if that seems to make sense.

Here is a modded ring with Eastwood's "Reflective Chrome" powder coat. It's pretty darn shiny! 

If I spent more time pre-buffing the raw metal, this would be darn purdy! This was done with just sand blast then medium wire wheel buff.

Goes real nice with the chrome locking cap!