V7 I / II Fuel Cap Replacement

[Dirk_S]

I’m looking at maybe buying a used V7 II fuel tank to install on my V7 III (it’s the right color and price, so why not?). The fuel cap for the V7 I & II is the type that sits flush inside the ring and simply locks, no screw mechanism. The tank does not come with a fuel cap, so I’d have to purchase a fuel cap as well. Two questions—

• Can the existing lock cylinder be easily drilled out on these fuel caps?
• Are there aftermarket options for this style of fuel cap, or do I have to go with an OEM fuel cap?

Pics for reference:

[malik]

It looks like it should fit, although dont know for sure. You will really want to see if you can get hold of a lockset- so you can go back to.one key only - cheaper from a parts wrecker. Refer to the Spare Parts Manual (the last page in some manuals) showing all 3 locks. Note that I think you'll find other models have the same cap & tank cap surround, for example the Cali 1100. Don't forget the cap surround.

[DoubleGuzzi]

This should be interesting, as I may be in a similar position. I'm not keen on a Monza style cap that's fitted to a steel tank on a V7 C. I think the matt Azzurro tank may have come from a V7 Stone but I don't know which series.
(I don't have a better pic, at this time..)




If you can reach the underside of the cap, then I reckon you might be able to remove/replace the lock without drilling.

[Dirk_S]

It looks like it should fit, although dont know for sure. You will really want to see if you can get hold of a lockset- so you can go back to.one key only - cheaper from a parts wrecker. Refer to the Spare Parts Manual (the last page in some manuals) showing all 3 locks. Note that I think you'll find other models have the same cap & tank cap surround, for example the Cali 1100. Don't forget the cap surround.

Sorry, Malik, I think I might’ve explained my query confusingly. The gas cap shown belongs to the same tank shown—both are off a V7 II. If I buy the tank and gas cap, I’ll obviously have to have a key for the gas cap. I’d prefer the lock match my existing key for the V7 III, so I was wondering if the lock cylinder can be replaced. The parts fiche for the V7 II, shown below, doesn’t show a separate cylinder—just the gas cap. Makes me wonder if perhaps the cylinder can’t be replaced at all.

[DoubleGuzzi]

^ I was about to give you bonus points for saying fuel instead of gas - you blew it! 

[Dirk_S]

^ I was about to give you bonus points for saying fuel instead of gas - you blew it! 

Well, fine. Then I’m knocking your Euro card for not defaulting to ‘petrol.’

[DoubleGuzzi]

Pounds, please, Scottish ones at that.

This image from Stein-Dinse suggests that the lock can be interchanged..

[Dirk_S]

Pounds, please, Scottish ones at that.

This image from Stein-Dinse suggests that the lock can be interchanged..

Excellent! My cursory search on S-D had only shown the gas cap with the lock cylinder already installed. Now, to figure out the type of cylinder. And I’ve never purchased a spare key or cylinder before, so I’m not sure if one can have a cylinder fitted to a key, or if it’s only the other way around.

[n3303j]

At least on my V11 the flush fit fuel cap disassembles and the cylinder is removable.

The pins (tabs) lock the cylinder in position through a slot in the lock body with the key out. When the key is inserted it shifts the pins (tabs) to a position where they are all flush with the cylinder and the cylinder can be rotated to the unlock position. (Yup, we already knew that stuff)

Now, if your ignition key is the same blank as the gas cap you can remove the lock cylinder and install your ignition key in that cylinder. Some pins will stick proud of the cylinder. Dress these flush with a flat file and then your ignition key will open the gas cap lock. When it locks it might be only one or two pins holding it shut but that's enough to keep gas in and folks honest.

You can fiddle with the order of the pins and maybe have to file off a bit less. Not necessary

This does not work on more complex locks that drop mating pins against the cylinder to detect cylinder pins that come up short.

[DoubleGuzzi]

I've done something similar for a 2nd hand topbox, where I didn't have the key. Removed and re-arranged some pins, so that the original ignition key could lock the topbox. IIRC I ended up with 4 pins instead of six, therefore not so "secure" but these locks are only an opportunistic deterrence anyway.
 

[DoubleGuzzi]

This might help,if you're thinking about trying the V7III lock on the other tank cap..
https://www.af1racing.com/606800m-oem-moto-guzzi-billet-gas-cap-blk-606800m
Scroll down for disassembly details.

Expensive options and cheaper with the lock and keys -go figure..
https://www.gutsibits.co.uk/pr/TheShop/index.php?f=e&Shnew=&Model=&ModelName=All%20Models&Cat=TAA&CatName=Tanks%20and%20Fittings&Sort=PriceDesc&spPage=1

Same item but cheaper and gives a full list of compatible bikes, so you know what to look for. 
https://www.stein-dinse.com/en/item-1-1024377.html

[malik]

I confirm that the (flush) fuel cap can be disassembled to remove the cylinder. Don't know anything about its internals. I got hold of a second hand lockset & took it apart to clean & polish when changing the locks on the 2014 V7 Special. You do have to watch the orientation of the cylinder within the cap on reassembly - insert it the wrong way & the key won't turn past the stop. Test with the key before buttoning it up. (Ask me how I know, for a while there I thought I might have wasted my money).

The ignition on the V7C melted in 2014. There was no new ignition in the country at the time, but there was a lockset. $AUD230 in 2014 dollars. Don't know what it would be in 2026 dollars. The ignition switch itself was then $180 odd to replace. Fast forward to 2024, the second hand lockset cost $AUD143, & in the following year the V7 Special's ignition switch failed. Parts on the shelf. Did have to pay for an extra 2 keys $34.

Good luck with playing with the cylinder insides. I had an idea that a decent locksmith should be able to cut a key to fit the lock mechanism, but all services cost. For me, changing all the locks was a neater solution.

[DoubleGuzzi]

Grabbed a used V7III type (screw in) cap this morning, that has no keys. I'll let you know how I get on re-keying it for the original V7C keys.
Wish me luck!
Even if I can't get it to lock, it won't matter to me too much, as the existing Monza cap ain't lockable anyway. 

[faffi]

Grabbed a used V7III type (screw in) cap this morning, that has no keys. I'll let you know how I get on re-keying it for the original V7C keys.
Wish me luck!
Even if I can't get it to lock, it won't matter to me too much, as the existing Monza cap ain't lockable anyway. 

I do not know the design of the key barrel, but even if you can just get one of the pins/slots working with the key will prevent someone to just open it easily with any key or screwdriver. FWIW, the old keyed tank caps on the Kawasaki KZ-series could be opened with anything, as there where no security built in whatsoever. Still safer than nothing, especially for those that do not know.

[DoubleGuzzi]

FWIW, the old keyed tank caps on the Kawasaki KZ-series could be opened with anything, as there where no security built in whatsoever. Still safer than nothing, especially for those that do not know.

I never tried, with my array of Kawas over the years.  Some toe rag did mangle the ignition on my 250 though - bar-steward!

[DoubleGuzzi]

I'm having a wee bit of a struggle undoing the large circlip on the underside of the top. My exchangeable heads circlip pliers keep popping off, just before the clip ends are squeezed enough to lift out the clip. Frustrating but hopefully I'll get there in the end.

[DoubleGuzzi]

Well, I purchased a cheap pair of fixed head supposedly heavy duty circlip pliers. When trying to undo the large circlip, a tip broke off almost immediately - a few choice words were said. Back to the original pliers and with the assistance of a third hand from my lovely assistant (I had to say that), I finally got the circlip off. Hurrah! That's the good news.

The key cylinder appears to be cast then pressed together, never to be opened. Reminds me of those cast metal toy cars and planes from the '70s. There are three indents, that look like the top of rivets but even when drilled out by approx. 1.5mm, the cylinder couldn't be split apart. More curses. I didn't want to go any further and..
Plan B. The cap arrived in the locked position i.e. the top and threaded portion are disengaged from each other. To 'unlock', a plastic peg juts out when the key is turned, engaging in a slot on the threaded portion, thus locking the threads to the top of the cap.
I enlarged the peg with black Polymorph, to constantly mesh the lock/cap top with the threaded portion. Now the cap looks like a locking one but it isn't - hey the Monza one doesn't lock either, so no big loss. The only other downside (for the anal-retentive) is the cap can't be rotated when on the tank, to keep the writing the "right way" around, when the cap is fully closed. Perhaps I can live with that on this particular bike. 

[Edit] Senior moment alert!
After I typed this up, I checked for the petrol resistance of Polymorph and it turns out that it can soften and degrade, being biodegradable in nature. Drat! I'll need to get the circlip off again and replace the Polymorph with Milliput. Best laid plans..

[faffi]

 

[DoubleGuzzi]

By demand..

 

 

[Antietam Classic Cycle]

If you buy a cap with no key, any locksmith worthy of the title should be able to cut a key to work in it.

[faffi]

Never seen a tank lid designed like that before. Looks complicated. My mailbox also have a lock that cannot be replaced, nor taken apart, due to the way it is made.

The cap on my V9 has no lock, which is rather unusual. Don't think I have had a lid with no lock since 1982.

[DoubleGuzzi]

If you buy a cap with no key, any locksmith worthy of the title should be able to cut a key to work in it.

Coincidentally, I made a search for local auto locksmiths yesterday. Too many recent outgoings to consider spending cash on such things for the foreseeable and too many other issues with the bike to resolve. 

[I'm not sure that the Milliput that I've used will harden up, given it's been in a cupboard for a few years. At least forking out for a new pack won't be limited to just this one task. Useful stuff to have handy.]

Looks complicated.

I likely made it sound worse than it is: a simple enough mechanism, albeit logically in reverse, apart from it (unnecessarily) being seemingly a sealed unit.

[ridingron]

I saw Stein-Dinse mentioned in several post above. As of today, they are not shipping to the U.S.

[Antietam Classic Cycle]

I saw Stein-Dinse mentioned in several post above. As of today, they are not shipping to the U.S.

Anything that Stein-Dinse sells can be ordered through MG Cycle and/or Crusty Cycle.

[DoubleGuzzi]

@Dirk_S
I should've mentioned before..
The Monza cap that I have, has an included screw in type adapter that makes it fit the V7III. The receipt for it shows that the cap was intended for a Triumph 900. Therefore, caps for the Street Twin 900 and other Bonneville variants of the same years are a viable alternative for the V7III tank.
That opens up a lot of other products, especially generic and aftermarket caps, from various outlets - even cheapo AilXpress ones. 
HTH

[Dirk_S]

Yeah, I had read in multiple posts on here, Reddit, and the GuzziTech forum that the gas cap for Triumphs fit. I would love to have a Monza style cap for my V9 cafe build, but I’m not ready to spend over $100 for one yet; I bought a cheap screw cap that at least looks like a legitimate moto tank cap and less of a 90s Transformers part like the OEM caps.

Back to my OP, I ended up finding a dentless V7 III tank at a fair value, and bought that instead of the V7 II tank.

BUT WORTH NOTING: I had Kev experiment for me, since he has both a Heron and a hemi model:

His V7 III key fits and turns the lock on his V7 Classic gas cap.

[DoubleGuzzi]

His V7 III key fits and turns the lock on his V7 Classic gas cap.

I unsuccessfully tried that with my two V7III caps. 
Good that you found something.
https://www.aliexpress.com/item/1005011929542001.html