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'09 R1200RT Fuel Tank Cap

rocketmanli

Chromehead
Now if BMW is going to build a really expensive bike like an RT, you think they wouldn't skimp on parts, right? Wrong....the entire bike is only as strong as its weakest link. The mechanism that keeps the gas cap propped open (that little 'click' sound when you open it) is controlled by this cheapo piece of plastic (the red one below). A roller pin goes into 2 microscopic holes at the end of the red thing as a pivot. My original one broke last year. Sure, BMW won't sell me the plastic part, nor tell me where to get it. They'd much rather I buy a brand new cap for about $250. So I took a shot and bought a used cap on Fleabay from a 2015 K1300S, and it happens to use the same piece (dumb luck). Now, after a year, the replacement one broke last weekend. If anyone else here has experienced this with any year bike, please let me know if you've come up with a better solution. Yeah I can leave it off, and then the lid would just flop around when open, which is no big deal. I just like when things work the way they're supposed to. I would assume a machine shop could make one out of metal. Just needs to be strong enough not to break, but flexible enough to spread a little to get the roller pin in. Just hard finding someone to make a one-off piece without it costing a fortune. Was hoping someone already did it, so I didn't have to re-invent the wheel.
 

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mine broke too, 2012 RT

Mine snapped one day, all of a sudden the click detente to keep the cap open was gone. I took it apart and it had broken in such a way that I was able to fix it with this stuff. I have used this to fix some other plastic pieces that would have been hopeless to repair by other means. If you cannot use this to repair yours you might try making a new piece of plastic to replace the little section that broke and gluing it onto the old base part. The weakness is the portion that holds the roller as I recall.

I also recall that this part being broken was more of an annoyance than a show stopper, so maybe you could just take it out and think about it for a while. A floppy gas cap when open shouldn't stop your ride.

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A flopping gas cap isn't just a hazard, it's a violation of Federal EPA laws - time for a recall...??
 
I replaced my cap with a screw in aluminum cap but you lose any semblance of security with that. Slingshot racing is the maker. I didn’t even know the detention existed as mine never stayed open since I bought the bike (used).
 
How violently are you guys opening the gas gap? Kidding here, but in general, I don't see why that part would break as it should have very little stress on it typically (unless you are rocking the nozzle onto the gas cap and applying pressure while fueling. I've had six bikes of this generation with the same gas cap and never had this happen. I also always fuel while sitting on the bike.
 
The cap doesn't flap when its closed; only when its open. This part has no effect on the closed cap. It just keeps it kind of stuck vertically when its open. And its not like I smash the gas nozzle into the cap while filling. IIRC I heard this thing snap, or break as I was closing the cap. All of a sudden, there's this weird extra pressure required to close the cap, and then "pop"....its done for. It seems (at least for me) to break where the roller pin goes into the hole in the red plastic holder. Won't be the end of the world if I never fix it or get another one. Would be nice if things just worked the way they were designed to work.
 
So it looks like you had one machined out of aluminum. Who did it and how much did it cost? And what holds it in place?
 
A friend did it. No cost (yet). Don't know what its made of but will be happy to share details after I pick it up. Its held in by a single screwed on clamp thing. I'll post a photo of that as well when I re-assemble it.
 
The cost was free and was done as a favor by a friend. He said it was very labor intensive and time consuming, and is not interested in fabricating any more. Hopefully these photos of the assembly will show you how its held in place. One screw holds the bracket down, and the roller pin slides against this bracket to lock the cap in place vertically when its open.
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I wonder if now that you have a good, working replacement, if the replacement could be scanned and later 3-D printed?
OM
 
RE: "if the replacement could be scanned and later 3-D printed?"

I've asked several friends who do 3D printing and they all suggested that the material used would most likely be more brittle than the original and wouldn't last long. From the markings on the OEM ones, a stupidly expensive mold was probably made, and the part was injection molded for mass production.
 
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