Chaps,

The fuel tank cap on my '89 K100 RT has been difficult to open since I bought the bike some months ago, and now the worst has happened. The key turns clockwise continuously and the lid don't open; the key will turn anti-clockwise about120 degrees and then "stop" but again the lid won't open.

If the lid won't open I can't put petrol in, and if I can't put petrol in I can't ride my bike! Does anyone know how to open the lid? Alternatively, does anyone know how to remove or bypass the lock and still open the lid? I talked to a locksmith, but all he said was "About $33-00" and I don't think he really knew what he was facing.

Help! (please).

Greg

The screws to remove the cap involve opening the cap, unfortunately. Depending how desperate you are, I'd suggest getting the biggest screwdriver that will fit and cranking it anti-clockwise to see what happens. Or, drilling out the lock, followed by draining and cleaning the tank.

I wouldn't try and lever the lip open - the tank's only aluminium so you'll probably damage it before getting the cap open.

Good luck!

hmm.... tricky one ...what to do ?....destroy the tank (possibly ) or disfigure the (now hard to get) tank fuel cap, or is that the other way round ?,

maybe just maybe a small drill hole towards the lock tongue at the front of the assembly ..might allow you to put some stong metal lever into it to pull the latch mechanism back so the lid can be opened .

there is a plastic cam assembly that connects via a couple of recesses /pins into the mechanism , which retracts the toungue ...i believe the plastic bits of the recess portion loose their edge after rotaing it the incorrect way and over time (corrosion of the tongue bits happens as well making the whole action ...erm not ..to the best design ) surely a brass cam action could have been developed .

hope this helps some

Mine in the same condition at the moment Greg, Awaiting parts to fix. I can open it with a bit of persistent fiddling using the following technique....

With fingers under the cap pressing it upwards strongly I rotate the key anticlockwise while pressing the toe of it towards the fronts of the bike and the fob to the rear. I may have to do this a few times until I find the catching point. Then when I feel the resistance on the key, a lilltle turn further to the left and POP...the cap opens from the finger pressure.

Good luck with it.

Will

I had the same exact problem over the summer, while in a trip 1000 miles from home. Iwas on my way to New Hampshire, I stoped for gas @ 150 miles like I always do. This time my key just spun around but did nothing.

I am lucky to get 175 miles out of a tank of fuel. So lets say I was a little worried.

I bought the bigest screwdriver the gas station had (it was just a Regular #2), I started ripping the lock out. It took me about 25 min to get the lock out.then you have to break it alittle more so you can pull the latch.

This part you won't believe .... but I swear it it true, I have witnesses.

This happened at lunch time. I am there beating on my tank with a screwdrive and a brick (no pun intended), when this guy comes over and asks what I am doing. I explain.

He tells me he works at this motorcycle shop about 6 miles from the gas station. They use to be a BMW shop, but not any more, but that the thought they had a tank with a cap, out back under a tree. Well sure enough they had one, and it had a key too! But guess what .... my key fits it too I only got the gas cap not the whole tank.



Look at the back or rear of the cap you will see a small hole on both sides. there is a pin in there. see if you can drive it out. Then you should be able to open it from the back.

good idea ..i like that one ...

I took my bike to a vehicle locksmith who pushed down on the key and cap (at the same time) whilst he or an assistant turned the key. The cap opened, luckily, after disassembling the cap he drilled the bottom of the lock to put in two pins where the white-metal pins had worn off. Now the lock works well and gives no cause for concern.

Chaps,

Thanks to all of you who provided solutions and suggestions. In my case because the lock barrel was simply rotating it was not possible to unlock it conventionally, no matter how we fiddled with the lid and hinges. Similarly, I could not find the 'oles and pin mentioned by Chuck Donahue, so off to the locksmith we went.

He tried to remove the lock barrel elegantly by drilling a small hole and releasing some locking lever in there, but that didn't work so it was back to brute force. He then drilled out some of the lock cylinder (without getting metal in the tank, because he didn't drill right through the latch mechanism), and removed the cylinder.

As Chuck points out, there are two pins cast as part of the lock barrel, and one of these had sheared off. This allowed the lock to rotate 360 degrees, and because one pin was missing, turning the lock didn't turn the actuating mechanism, a cam which slides the latch tongue back. Putting two small diameter Allan keys (hex wrenches to North Americans?) into the holes, and placing a large, flat bladed screwdriver between them rotated the actuating mechanism enough to slide the latch tongue back and allowed us to open the cap. If you are caught in a similar situation, the screwdriver had a blade about 13 mm or half an inch across, and was inserted *vertically* between the pins; turning the screwdriver as if undoing a right-hand thread applies pressure to the Allan keys down low where they enter the holes in the actuating mechanism. All of this took about thirty minutes, and set me back thirty pictures of the Queen, which I thought was good value.

Three Phillips-head screws inside the cap allowed me to remove the actuating mechanism, which is in three major parts: a) the circular plastic body, b) the latch tongue, which slides horizontally across the bottom of the circular body, and c) the "cam body", which is a plastic cylinder. This cylinder is closed at one end, with a small snail cam moulded onto the outside surface of the closed end. Inside the closed end are the two holes into which the pins on the lock barrel mate, and the lock barrel is a neat sliding fit inside the cam body; turning the lock turns the cam body and the cam makes the latch tongue slide backwards. If you are tempted to disassemble this mechanism, be aware that there is a coiled compression spring inside the latch tongue to force said tongue into the cap-locked position when the cam is released. There is also a small circular snail-type spring under the cam body which forces the cam body and lock barrel to return to the tank-locked position when key pressure is released. If you pull it apart, I encourage you to do so under a piece of clean cloth so that you can recover the springs easily, and not spend half an hour crawling short-sightedly around the workshop floor, muttering imprecations whilst searching for very small springs.

If you need to find parts may I suggest that you look at http://www.munichmotorcycles.com.au; they seem to have lotsa parts of all sorts, and their website is easy to navigate. Note that I found that it is possible to purchase just the lock barrel, for AUD$35-00, which seems good to me; see this link - http://www.munichmotorcycles.com.au/product_info.php?products_id=1876

So now I can, and have, put fuel in the tank and go for a ride. Great 22 degrees C weather, sunshine, and a wasp in the eye (sigh). Ah well, every silver lining has a bloody big dark cloud wrapped around it.

Greg

good explanation greg ....and good to hear that you got it going again ....happy riding mate !!!

Obviously you are the key person for this information. Never lock away that knowledge.

22 C ?? its 27 C north side of town and I still can't ride the old girl ( bloody broken ankle ) tho have done 650 metres in the last 7 weeks on the main stand

I'm in the hills, Toto; it was 22C this morning . Sorry to hear about your busted fetlock, and I trust it will improve soon. How didja do the 650 metres? Sitting on the saddle and saying "Brrrmmm! Clunk! Brrrmmm! Clunk!" with your eyes closed, or was it something more serious than that?

G'day greg wish was sitting in the saddle , just starting the old girl once or twice a week to keep battery charged ( got a u beaut battery charger but one the kids borrowed it ....grrrrrrrr) finally hobbling around bare feet so hope to make the swap meet in Gawler on the 20 th this month ( proceeds to kids cancer so good cause )

Swap meet in Gawler? Where? I might go.

Event Details
A SWAP MEET not to be missed!

If you have motorcycle parts from a restoration project lying around or need to clean out your shed of old bike parts, then put the 20th NOVEMBER in your diary now and get the trailer loaded.

Gates for SELLERS open at 6am – trailers $10. Gates are open to BUYERS at 8am – admission $5 per person.

Enjoy breakfast on the grounds before you start looking over the 1,000′s of items.

Participate in the Show & Shine. Registration required before the day via email motorcycleswapmeet@gawlerlightrotary.org.au

Join in the MRA organised Group Ride. Starting at Tea Tree Plaza to Gawler via Chain of Ponds. Leaving Tea Tree Plaza, Civic Park at 9.30am.




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Damn I've had to much time off with this ankle just noticed I got wrong month or is that
a senior moment

Guest wrote:I took my bike to a vehicle locksmith who pushed down on the key and cap (at the same time) whilst he or an assistant turned the key. The cap opened, luckily, after disassembling the cap he drilled the bottom of the lock to put in two pins where the white-metal pins had worn off. Now the lock works well and gives no cause for concern.

Hey thanks for all the tips and tricks. I really thought I was screwed with a jammed filler cap and it seems the press down on the key bit was that magic bit of knowledge which got me out of  a tight corner.

I had already been pressing on the cap to release pressure on the mechanism but had not thought that pressing on the key would help.

Now I have it open, life suddenly becomes a lot more manageable.



I have a follow up question. I have another bike where the lock actually pulled out. The bike was left outside for about a year and when I tried to open the tank, the key got jammed in the lock.  I wiggled, jiggled and sprayed WD40 into it but no way would it come out. Fortunately (?) the key was on a ring, so was able to get a finger through the ring and pull.

Much to my pleasure the key came out ... until I realised the lock was still on they key.

That was my previous contact with a jammed filler cap and since the bike was not running it just stayed where it was. ( After I'd made some cosmetic adjustments to the shape of the tank ! ) I may now ( or rather, later when I've fix the real bike ) be able to use my new found knowledge to open that cap too but what I need to know is whether it is possible to replace the broken lock. I'm not sure what exactly gave way when it came out but assuming I can now open the cap with a 1/2" screwdriver and two small Allen keys,  is it possible to change the lock , and how ?

TIA.

The locks are available from Motobins or Motorworks. You have to undo and remove the three screws that hold the vent catch assembly exposing the lock. With your key in you can push in the detent and remove the lock, To insert the new lock you will need to push in the detent. I used a sliver of plastic cut from a blister pack this was inserted into the lock from the back enough for the detent to ride up over the plastic pushing it in. The plastic was then pulled out allowing the detent to pop out. Replacing the catch assembly is a little tricky but there is a  YouTube video on how to assemble it.
Regards Martin.

Had you searched 'How to open a petrol tank with a broken lock' you would have found this, there's no need to wreck the cap.

 https://www.k100-forum.com/t9469-open-a-petrol-tank-cap-which-has-a-broken-lock#111842

Paul.