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Discussion Starter · #83 ·
If this tank comes to market, IMS should engrave Westieterrier's name into a small, hidden area of the mold in homage to his efforts.
That's kind of you to say PS! But I'm doing this (as well as the Dyno test, etc.) for this awesome community. It is to both pay back the community for the wonderful guidance it has given me, as well as earn some points for the many uninformed (i.e., stupid?) questions I will have in the future. There's a dozen or more guys on here who spend alot of time posting pictures and explaining all kinds of things to us newcomers. I'm not allowed by law to send IPAs across state lines to everyone of them that have helped me, so this is my way of expressing gratitude. More to come . . . . Thanks. Patrick
 

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A form fitting 4+ gallon tank would be nice with the stipulation that reserve properly drains the tank. I'm sporting a Clarke 4.1 now and routinely hit reserve @ 170 miles when there is still plenty of daylight. I'm still working out my reserve range but it seems like there is lots of fuel left and the center hump impedes transfer. Or to spin it in a positive light, my reserve has a reserve.

I have a 4.1 on my XT, and just this past weekend ran it dry to see what my total range would be. I went 180 miles before reserve, and then ran dry at 251.3 miles, which means that the reserve is good for about 70 miles. I REALLY like that nice reserve as where I live, even if I really screw the pooch, I should be able to find fuel within 70 miles...

This was with a new Yamaha XT225 petcock in the tank. Different petcocks with different length standpipes will cause differences in the above numbers, as will individual bike's fuel economy, obviously. In my case, none of those miles were gentle though.

Granted, you are correct in that a little fuel remains in the lower front "lobe" on the left side, but it's not a lot of fuel at all. And on the right, there is a bit more. So, yeah, a little reserve for the reserve... If needed, I can lay the bike to the left side to transfer all that remains on the right to the petcock side, and likely get a few more miles.

Here's mine once I ran it dry...

Left side:

213381



Right side:


213382



And after adding the contents of one of the fuel bottles I took along for this little experiment:


213383



But yeah, with four gallons, I KNOW that I can comfortably go 200 miles on a tank while still having a 50 mile "cushion". :) (y)
 

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I said "trying" to live off the land, I ended up losing a few pounds. Even with short coconut trees it was rather difficult for a Haole boy like me to harvest and open coconuts with only a pocket knife, but thirst is a great motivator. Shredding the husk and cracking open a mature nut for the meat burns a lot of calories too. Many a tasty looking guava & papaya were too high out of reach and I'm no climbing monkey. But the experience of immersion in the environment was worth the sunburn, the itch of dried saltwater and the unusual bugs at night. Juvenile Spinner dolphins can be quite inquisitive and playful with a silly human who couldn't dive very deep nor hold his breath for very long.:)
View attachment 213322

Seeing native Hawaiians keep alive a sense of hunter-gatherer skills was impressive, they could kick my butt with survival skills while I would starve . Not atypical to see a powerboat pull up to into a sheltered remote bay for a picnic with very little store bought food. The guys would go out with nets and sling spears, the gals comb the tide pools for shellfish and jungle for whatever. In short order they would bring together all their collected sustainable harvest , cook it up and have a family feast. Take that Safeway!
Man, I totally hijacked this thread about gas tanks, sorry.
 

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Fred
I like your adventure in Hawaii rant. I live on the Big Island not sure where you were guava hunting. Probably the best place on earth for living off the land and a lot of people do it. Unfortunately too many of them avoid the water too much which is unfortunate because that is where most of the food is and ...... it would be a benefit to others they come into contact with .... if you catch my whiff, or more so theirs🤢
Anyways sent in my vote for a less intrusive 3-3.5gal tank because we can always carry and extra rotopax if needed where a 4plus gal tank will always be there no matter what.
Getting the TW I have on the mainland (in Montana) ready for a planned TW only trip across country on the TAT around September and with that we are definitely going to require extra fuel. Have a Clark tank on standby.
 

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Discussion Starter · #88 ·
I have a 4.1 on my XT, and just this past weekend ran it dry to see what my total range would be. I went 180 miles before reserve, and then ran dry at 251.3 miles, which means that the reserve is good for about 70 miles. I REALLY like that nice reserve as where I live, even if I really screw the pooch, I should be able to find fuel within 70 miles...

This was with a new Yamaha XT225 petcock in the tank. Different petcocks with different length standpipes will cause differences in the above numbers, as will individual bike's fuel economy, obviously. In my case, none of those miles were gentle though.

Granted, you are correct in that a little fuel remains in the lower front "lobe" on the left side, but it's not a lot of fuel at all. And on the right, there is a bit more. So, yeah, a little reserve for the reserve... If needed, I can lay the bike to the left side to transfer all that remains on the right to the petcock side, and likely get a few more miles.

Here's mine once I ran it dry...

Left side:

View attachment 213381


Right side:


View attachment 213382


And after adding the contents of one of the fuel bottles I took along for this little experiment:


View attachment 213383


But yeah, with four gallons, I KNOW that I can comfortably go 200 miles on a tank while still having a 50 mile "cushion". :) (y)
This is very helpful. How much orphan gas do you think was left? Fred’s 1/3 gallon? Maybe a pickup tube inside the tank would help? P
 

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This is very helpful. How much orphan gas do you think was left? Fred’s 1/3 gallon? Maybe a pickup tube inside the tank would help? P

I can't say, really, as I didn't remove the tank and drain it to measure what remained. As you can see from the photos above, the left side only had a little fuel remaining in the front lobe portion. Just looking at the thickness of the tank in this location, I wouldn't think that it was much at all. The right side holds a bit more obviously, because of the frame hump, so it still had some fuel all the way across, front to back. But again, laying the bike over on the left will get all of that over to the petcock side. Some may say that's a PITA. But to me, that just gives me a little "safety cushion" against stupidity. We all like to think we're immune to acts of stupidity... But, I know I'm not... In fact, that little leftover fuel on the right side saved me once on another bike when I filled up and forgot to switch the petcock back from the reserve position to On. On that occasion, if I had used ALL of the fuel in the tank I would have been hosed. But, by laying the bike over, I had enough left to get to gas. So, for me personally, I don't mind the right side leftovers. With the XT's tank shape, it's really just that left front lobe portion that's actually completely inaccessible.

But with the way the petcock is positioned within the side panels of the XT, the petcock location is restricted. The TW doesn't have this problem... So, just looking at mine, I believe that the tank could be made to hold a bit more by lowering the petcock a bit. With a gravity feed system, all you need is for the fuel to be above the inlet spigot on the carb, after all... As long as the bottom of the tank where the petcock mounts is above the needle and seat valve, fuel will flow into the float bowl.

And then, I really wish my tank was wider as well. With the way my XT tank is shaped, I can get a much better grip with my legs while standing due to the way that tank flairs out a bit toward the front. I feel the TW's tank is too narrow, doesn't flair out enough, and with the slickness of the material, I basically have no grip with my legs while standing. I'd MUCH prefer the tank if its shape as more like the tank on the XT. By lowering the tank somewhat, and adding to the width a bit, with a flair toward the front, even the basic shape of the Clarke TW tank could be made to hold quite a bit more than it does now. And then there's a lot of wasted space on the lower front, below the front mounting bolt. If this area was extended further forward rather than sloping down and back, along with a bit of width behind the fork recesses, I'm pretty sure a tank could be made for the TW that would hold considerably more, and without causing any issues with clearances or ergos. With those thoughts in mind, I still don't understand why there are those that would prefer a tank that holds less than is reasonably possible and that comes with no fitment issues or other negatives... 🤷‍♂️ And I still feel that a bit more width would make the tank BETTER in ways other than just the added capacity that it would allow... So, I'm looking at more than just capacity when it comes to improving what is already on the market with the Clarke TW tank...

And as far as carrying a Rotopax... That's all fine and good. If one needs more then that's understandable. But... A Rotopax cost more money. It adds weight to the rear of the bike, where you really don't want/need it. It takes up space that could otherwise be used for luggage, tools, what have you.... I'd MUCH rather carry my full fuel load in the gas tank where it belongs, where it creates a better weight distribution, and where I don't have to deal with unloading my gear to access a Rotopax or transferring fuel to the main tank. Why bother with all of that if I can have a tank that will accept more fuel? And for those that like their Rotopaxs, and travel into remote locations where more fuel is always better... Ok, I get that too. So, wouldn't a 4 gallon tank and a 1 gallon Rotopax be better than a 3 gallon tank and a 1 gallon Rotopax? What are the negatives of a 4 gallon tank if IMS can make one that holds that quantity, bolts straight on the bike with no modifications, and doesn't cause clearance or ergonomic issues?

I've actually read elsewhere, people saying they didn't want to always be carrying around that much weight... :unsure: Hmmm... Well, let's see... Here's an idea... Don't fill the tank up for those trips... I have a 4 gallon on the XT for those times where I want to go some distance and not have to worry about fuel. And there in lies the rub... There are some riders that don't ride that far at a time... I use my bikes as mini-adv bikes though. My typical day is likely to be in excess of 200 miles, and 250 has been done on more than one occasion. I have a trip on the SM500 scheduled in May, and plan to ride the SEAT later this year as well. For those other days where I don't plan on going that far, I just put 2 or 3 gallons in the tank...


With all that said, I really don't know what IMS can do... It's difficult for me to visualize volume in a complex shape like a motorcycle tank. But, I would guess that IMS can easily knock up some shapes in a CAD program or something and easily calculate volumes to see what will fit within the confines of the bike design. If they come back and say X is the most we can do without this concession or that, then ok... But, I just see no point in asking for less than is possible as long as it can be done with no negatives involved.... Ask for the world, and if the designers come back and say, "I can only give you half of it", then ok. But ask for half, and you'll never know what could have been possible....

To my way of thinking, wouldn't it be better to NOT specify a quantity, and simply say something to the effect of, "As much as is feasible, as long as it bolts on with no major modifications, causes no clearance issues, and doesn't negatively impact the ergonomic fit of the rider/bike interface"?

Just my thoughts on the subject....
 

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Seems to me I remember the gas amount as being about a pint.
 
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Discussion Starter · #92 ·
I can't say, really, as I didn't remove the tank and drain it to measure what remained. As you can see from the photos above, the left side only had a little fuel remaining in the front lobe portion. Just looking at the thickness of the tank in this location, I wouldn't think that it was much at all. The right side holds a bit more obviously, because of the frame hump, so it still had some fuel all the way across, front to back. But again, laying the bike over on the left will get all of that over to the petcock side. Some may say that's a PITA. But to me, that just gives me a little "safety cushion" against stupidity. We all like to think we're immune to acts of stupidity... But, I know I'm not... In fact, that little leftover fuel on the right side saved me once on another bike when I filled up and forgot to switch the petcock back from the reserve position to On. On that occasion, if I had used ALL of the fuel in the tank I would have been hosed. But, by laying the bike over, I had enough left to get to gas. So, for me personally, I don't mind the right side leftovers. With the XT's tank shape, it's really just that left front lobe portion that's actually completely inaccessible.

But with the way the petcock is positioned within the side panels of the XT, the petcock location is restricted. The TW doesn't have this problem... So, just looking at mine, I believe that the tank could be made to hold a bit more by lowering the petcock a bit. With a gravity feed system, all you need is for the fuel to be above the inlet spigot on the carb, after all... As long as the bottom of the tank where the petcock mounts is above the needle and seat valve, fuel will flow into the float bowl.

And then, I really wish my tank was wider as well. With the way my XT tank is shaped, I can get a much better grip with my legs while standing due to the way that tank flairs out a bit toward the front. I feel the TW's tank is too narrow, doesn't flair out enough, and with the slickness of the material, I basically have no grip with my legs while standing. I'd MUCH prefer the tank if its shape as more like the tank on the XT. By lowering the tank somewhat, and adding to the width a bit, with a flair toward the front, even the basic shape of the Clarke TW tank could be made to hold quite a bit more than it does now. And then there's a lot of wasted space on the lower front, below the front mounting bolt. If this area was extended further forward rather than sloping down and back, along with a bit of width behind the fork recesses, I'm pretty sure a tank could be made for the TW that would hold considerably more, and without causing any issues with clearances or ergos. With those thoughts in mind, I still don't understand why there are those that would prefer a tank that holds less than is reasonably possible and that comes with no fitment issues or other negatives... 🤷‍♂️ And I still feel that a bit more width would make the tank BETTER in ways other than just the added capacity that it would allow... So, I'm looking at more than just capacity when it comes to improving what is already on the market with the Clarke TW tank...

And as far as carrying a Rotopax... That's all fine and good. If one needs more then that's understandable. But... A Rotopax cost more money. It adds weight to the rear of the bike, where you really don't want/need it. It takes up space that could otherwise be used for luggage, tools, what have you.... I'd MUCH rather carry my full fuel load in the gas tank where it belongs, where it creates a better weight distribution, and where I don't have to deal with unloading my gear to access a Rotopax or transferring fuel to the main tank. Why bother with all of that if I can have a tank that will accept more fuel? And for those that like their Rotopaxs, and travel into remote locations where more fuel is always better... Ok, I get that too. So, wouldn't a 4 gallon tank and a 1 gallon Rotopax be better than a 3 gallon tank and a 1 gallon Rotopax? What are the negatives of a 4 gallon tank if IMS can make one that holds that quantity, bolts straight on the bike with no modifications, and doesn't cause clearance or ergonomic issues?

I've actually read elsewhere, people saying they didn't want to always be carrying around that much weight... :unsure: Hmmm... Well, let's see... Here's an idea... Don't fill the tank up for those trips... I have a 4 gallon on the XT for those times where I want to go some distance and not have to worry about fuel. And there in lies the rub... There are some riders that don't ride that far at a time... I use my bikes as mini-adv bikes though. My typical day is likely to be in excess of 200 miles, and 250 has been done on more than one occasion. I have a trip on the SM500 scheduled in May, and plan to ride the SEAT later this year as well. For those other days where I don't plan on going that far, I just put 2 or 3 gallons in the tank...


With all that said, I really don't know what IMS can do... It's difficult for me to visualize volume in a complex shape like a motorcycle tank. But, I would guess that IMS can easily knock up some shapes in a CAD program or something and easily calculate volumes to see what will fit within the confines of the bike design. If they come back and say X is the most we can do without this concession or that, then ok... But, I just see no point in asking for less than is possible as long as it can be done with no negatives involved.... Ask for the world, and if the designers come back and say, "I can only give you half of it", then ok. But ask for half, and you'll never know what could have been possible....

To my way of thinking, wouldn't it be better to NOT specify a quantity, and simply say something to the effect of, "As much as is feasible, as long as it bolts on with no major modifications, causes no clearance issues, and doesn't negatively impact the ergonomic fit of the rider/bike interface"?

Just my thoughts on the subject....
Beautiful post IP !! You've eloquently expressed the same feelings I have on just about every single point. I'm not experienced enough off-road to appreciate the "tank gripping" comments yet as I am merely trying at this beginner level to just 'keep the rubber side down.' I imagine I will identify with what you're saying on leg positioning perhaps this summer. Awesome!

Considering that you've done such a great job here, perhaps you can give Daniel or Chris a call at IMS: (951) 653-7720 PCT. Tell them what you say above. They're super friendly Californians.

Regarding fuel left in the tank, I've now read a number of old posts regarding the XT tanks on this forum, and one knowledgeable person stated that a small amount of fuel left in the tank is a good thing as it captures debris and impurities by design. The person further stated that most motorcycle tanks are made in such manner. Interesting.

Lastly, one final question. How would you compare the Clarke XT225 4.1 tank to the XT350 4.0 tank? Which one has a cleaner fit? If IMS does not come through with a definitive answer, I will be heading in that direction. Thank you for all your work here!!
Patrick
 

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Beautiful post IP !! You've eloquently expressed the same feelings I have on just about every single point. I'm not experienced enough off-road to appreciate the "tank gripping" comments yet as I am merely trying at this beginner level to just 'keep the rubber side down.' I imagine I will identify with what you're saying on leg positioning perhaps this summer. Awesome!

Considering that you've done such a great job here, perhaps you can give Daniel or Chris a call at IMS: (951) 653-7720 PCT. Tell them what you say above. They're super friendly Californians.

Regarding fuel left in the tank, I've now read a number of old posts regarding the XT tanks on this forum, and one knowledgeable person stated that a small amount of fuel left in the tank is a good thing as it captures debris and impurities by design. The person further stated that most motorcycle tanks are made in such manner. Interesting.

Lastly, one final question. How would you compare the Clarke XT225 4.1 tank to the XT350 4.0 tank? Which one has a cleaner fit? If IMS does not come through with a definitive answer, I will be heading in that direction. Thank you for all your work here!!
Patrick
I have the XT225 tank on both of mine. Based on my reading of the same forum posts/tutorials that you have probably read, it looked to me that the 225 was a more natural fit in terms of mounting and seat fitment.
For the record, I'm not necessarily a Clarke fanboy. However, I think a lot of guys make too big of a deal about their TW mold flaw. It's a well known issue, doesn't affect function, and Clarke discounts that model according. I chose the XT225 over the TW tank solely for the extra capacity.
If IMS made a 4 gal direct fit it would negate the need for guys to retrofit an XT tank, Clarke or OEM. Bonus points if it works without modifying the side panels. I'm not sure I'd toss my Clarkes in favor of an IMS, but if I bought another bike, I'd absolutely go with the more direct fit of the two. And I'd certainly recommend it to new owners too.
 

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I can't say, really, as I didn't remove the tank and drain it to measure what remained. As you can see from the photos above, the left side only had a little fuel remaining in the front lobe portion. Just looking at the thickness of the tank in this location, I wouldn't think that it was much at all. The right side holds a bit more obviously, because of the frame hump, so it still had some fuel all the way across, front to back. But again, laying the bike over on the left will get all of that over to the petcock side. Some may say that's a PITA. But to me, that just gives me a little "safety cushion" against stupidity. We all like to think we're immune to acts of stupidity... But, I know I'm not... In fact, that little leftover fuel on the right side saved me once on another bike when I filled up and forgot to switch the petcock back from the reserve position to On. On that occasion, if I had used ALL of the fuel in the tank I would have been hosed. But, by laying the bike over, I had enough left to get to gas. So, for me personally, I don't mind the right side leftovers. With the XT's tank shape, it's really just that left front lobe portion that's actually completely inaccessible.

But with the way the petcock is positioned within the side panels of the XT, the petcock location is restricted. The TW doesn't have this problem... So, just looking at mine, I believe that the tank could be made to hold a bit more by lowering the petcock a bit. With a gravity feed system, all you need is for the fuel to be above the inlet spigot on the carb, after all... As long as the bottom of the tank where the petcock mounts is above the needle and seat valve, fuel will flow into the float bowl.

And then, I really wish my tank was wider as well. With the way my XT tank is shaped, I can get a much better grip with my legs while standing due to the way that tank flairs out a bit toward the front. I feel the TW's tank is too narrow, doesn't flair out enough, and with the slickness of the material, I basically have no grip with my legs while standing. I'd MUCH prefer the tank if its shape as more like the tank on the XT. By lowering the tank somewhat, and adding to the width a bit, with a flair toward the front, even the basic shape of the Clarke TW tank could be made to hold quite a bit more than it does now. And then there's a lot of wasted space on the lower front, below the front mounting bolt. If this area was extended further forward rather than sloping down and back, along with a bit of width behind the fork recesses, I'm pretty sure a tank could be made for the TW that would hold considerably more, and without causing any issues with clearances or ergos. With those thoughts in mind, I still don't understand why there are those that would prefer a tank that holds less than is reasonably possible and that comes with no fitment issues or other negatives... 🤷‍♂️ And I still feel that a bit more width would make the tank BETTER in ways other than just the added capacity that it would allow... So, I'm looking at more than just capacity when it comes to improving what is already on the market with the Clarke TW tank...

And as far as carrying a Rotopax... That's all fine and good. If one needs more then that's understandable. But... A Rotopax cost more money. It adds weight to the rear of the bike, where you really don't want/need it. It takes up space that could otherwise be used for luggage, tools, what have you.... I'd MUCH rather carry my full fuel load in the gas tank where it belongs, where it creates a better weight distribution, and where I don't have to deal with unloading my gear to access a Rotopax or transferring fuel to the main tank. Why bother with all of that if I can have a tank that will accept more fuel? And for those that like their Rotopaxs, and travel into remote locations where more fuel is always better... Ok, I get that too. So, wouldn't a 4 gallon tank and a 1 gallon Rotopax be better than a 3 gallon tank and a 1 gallon Rotopax? What are the negatives of a 4 gallon tank if IMS can make one that holds that quantity, bolts straight on the bike with no modifications, and doesn't cause clearance or ergonomic issues?

I've actually read elsewhere, people saying they didn't want to always be carrying around that much weight... :unsure: Hmmm... Well, let's see... Here's an idea... Don't fill the tank up for those trips... I have a 4 gallon on the XT for those times where I want to go some distance and not have to worry about fuel. And there in lies the rub... There are some riders that don't ride that far at a time... I use my bikes as mini-adv bikes though. My typical day is likely to be in excess of 200 miles, and 250 has been done on more than one occasion. I have a trip on the SM500 scheduled in May, and plan to ride the SEAT later this year as well. For those other days where I don't plan on going that far, I just put 2 or 3 gallons in the tank...


With all that said, I really don't know what IMS can do... It's difficult for me to visualize volume in a complex shape like a motorcycle tank. But, I would guess that IMS can easily knock up some shapes in a CAD program or something and easily calculate volumes to see what will fit within the confines of the bike design. If they come back and say X is the most we can do without this concession or that, then ok... But, I just see no point in asking for less than is possible as long as it can be done with no negatives involved.... Ask for the world, and if the designers come back and say, "I can only give you half of it", then ok. But ask for half, and you'll never know what could have been possible....

To my way of thinking, wouldn't it be better to NOT specify a quantity, and simply say something to the effect of, "As much as is feasible, as long as it bolts on with no major modifications, causes no clearance issues, and doesn't negatively impact the ergonomic fit of the rider/bike interface"?

Just my thoughts on the subject....
Let's just let ims give us the best , biggest tank that they can
One that holds some of the fuel low as possible on the bike
Without the need of a fuel pump and doesn't trap engine heat
And boil the fuel..
If this requires dual petcocks or a crossover line so be it..
A quality tank that fits well...
Ims is very good at what they do..
This tank could easily be as large as 4.5 gallons...
If it's to big for you just don't fill it all the way up..
A tank like this with 2.5 to 3 gallons in it would be less top heavy then stock..
As stated before there are other advantages to a large tank other
Then the amount of fuel it will hold ....
Grip for control and CRASH protection are only two..
Let's stop arguing about plus or minus a half gallon
and just hope like hell they are willing to help us at all....
mike from NC
 

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Have we heard back from them at all since this started?
 
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Let's stop arguing about plus or minus a half gallon
and just hope like hell they are willing to help us at all....
mike from NC
I don't see any arguing. Merely discussing of opinions. Thank goodness we have different opinions. Hopefully they will monitor this thread and take into consideration differing opinions.

Heck I'll throw in another attribute, that hasn't been discussed much.

Aesthetical value. It should look proper. The size, shape, and color are determining factors on how a bike looks. That's why custom bikes often have custom or non-stock tanks. And yes the TW is a utilitarian bike, there is no need to have it look like I'm going out to spray the crops with it, or look like I (poorly) fabbed it myself, like many of the other tanks mods end up looking.

But I agree, IMS appears to make high quality products. I'm sure they will prototype and deliberate and hopefully come up with a reasonable offering to us.

In the end, some will like it, some won't.
 

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Making a larger tank and keeping the weight down low is going to be a real challenge. Petcock location is going to be the first one and I can see a fuel pump being needed.
 

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unless they emboss pretty flowers on the sides or a picture of Wonder Woman.
Just like lunchboxes. Make mine the Monkees.

"Now with your favorite super hero! Collect them all: Wonder Woman, Superman, Urkel, Robin, and the entire band of Ewoks from Star Wars!" Caution: Collector edition tanks not suitable for use with gasoline or other liquids.
 
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