Gas cap rebuild

[redtank]

Well my '88 K75 gas cap is extremely difficult to open with the ignition key. I'm afraid of breaking off the key at some point. I push down on the cap while turning the key, but doesn't help at all. Do I need to rebuild the cap and if so can someone provide me with a part number for rebuild kit? I've watched a Youtube video showing the rebuild, but it didn't really address difficulty in getting cap open. When it rains really hard on K bike, water finds its way into tank regardless.

Thanks,
Cris

[RobP]

I had the same 'zact issue with my K100 gas cap.  Almost impossible to open without a lot of fettling about.

See here:  http://www.motobrick.com/index.php/topic,494.0.html

Scroll down, down, down until you see the picture of the lock tumbler with the wafers.  Leave the outermost retaining wafer intact, but then use a dremel or file to turn down the high wafers (when the key is in position).  I don't know how mine got so out of whack, unless the PO did a swap, but grinding the inner wafers flush did the trick.

[redtank]

RobP,
Okay, first thanks for the reply. I don't see how re-keying my gas cap is going to make it easier to open and how is that'going to replace the worn gaskets. I need the part number for the rebuild kit and need to know what component (in the tumbler) needs to be relieved in order to make it easier to open the gas cap. Maybe I'm missing something in the website you pointed me to?

Thanks,
Cris

[rbm]

BMW Part No. 16 11 9 062 461

[redtank]

rbm,
Thanks for the part number, I'm replacing all fuel lines this weekend so I'm going to have a go at the lock tumbler because RobP had luck working on his. I'm also going to lube bikes clutch splines so will be down for a week or two.

Cris

[rbm]

Lubricating the lock catch mechanism will go a long way to making the mechanism function easier.  A good moly lubricant like what you will use on the splines will be best.