Caswell liner failure

My '83 BMW R100RS came with a red liner in the tank (I think it may be a stock BMW thingy) and it seems a tad "flakey" so I may have to re-do it.

The one thing about POR15 is: it doesn't seem to react to anything. In other words, I haven't run across anything that softens it or acts as a solvent.

While that does suggest that it makes a great tank liner, it also means that if you get even the smallest drop on the outside of a painted tank....it will likely be there till he!! freezes over.
 
First Norton I owned had the factory fiberglass tank.... '70-'71 maybe. :umm:
No liner, never had a problem. 'Course, that was pre ethanol days.
Yeah the Norton guys won't use any of those old factory glass tanks on a bet now, they didn't age well.
:twocents: Pretty much true of all fiberglass it doesn't age well.
 
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What do you think gas station fuel storage tanks -- the ones underground -- are made of? Well, I wondered too, so I Googled it. Here's a prominent result:
https://www.nwpump.com/petroleum/petroleum-products/storage-tanks/
They sell tanks. They say that steel tanks are cheapest. Then they go on to say, and I quote:

Fiberglass tanks are a rust-proof option in this age of ethanol fuels and biodiesel fuel products, offering some distinct advantages to traditional steel.

So, believe what you want about fiberglass motorcycle tanks.

Trophies.jpg

I built the above bike in 2014. That's early Omar's glass. The tank was already several years old when I got it in 2014. I don't remember if there were any signs of it ever having gas in it when I got it. I used to have a pic of Kenny Roberts on an XS650 that had the same tank with the exact same graphics on it -- which I'm pretty sure were paint, not decals, if that's possible.
Anyways, at that time, 2014, Omar's said that the only tank liner that worked with fiberglass was Caswell. They would Caswell the tank that you were buying from them for a little extra. Yes, ethanol gas was everywhere in 2014.
So, I lined the tank with Caswell's. Used nothing but E10 in it. Never drained it. Rode it for a least year after I completed it. Sold it to a guy in south Texas. He'd call me every couple years to tell me how much he loved it. Never had any problems with the tank.

I've used Caswell many, many times since. It now comes in several colors, black, blue, grey, red, etc.
I've lined over failed Kreme liners more than once with no problems.
The only time I ever had a problem was when I made the mistake of measuring the proportions by weight instead of volume. It would not harden, but turned rubbery. I fixed it by re-lining with properly proportioned Caswell's. That was several years ago and the tank has been on my daily rider ever since.
By the way, I asked Caswell to give me the by-weight mixing proportions, and they didn't know what they were, a real shortcoming if you ask me. I mean, how hard can it be for them to figure it out? I have since calculated the by-weight proportions myself, not hard to do.

Final word: yes, E10 is nasty, but it's really nasty when it gets old. You need to keep cycling it, in other words you need to ride your bike enough that you're putting fresh gas in it like every three months or so at the most. If the gas is going to sit longer than that, I strongly recommend an ethanol fuel stabilizer. Which is a topic for a whole 'nother thread, and there are several on this Forum. The stabilizer I think is best is called "Ethanol Shield." It was little-known in 2014, but now Lowe's, Home Depot, and Walmart have it in-store.
Final final word -- I ride my bikes enough that I see no need for Ethanol Shield. But I ALWAYS used it in my Caswell's-lined Omar's tank, and I told the guy I sold it to to do the same.
 
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What do you think gas station fuel storage tanks -- the ones underground -- are made of? Well, I wondered too, so I Googled it. Here's a prominent result:
https://www.nwpump.com/petroleum/petroleum-products/storage-tanks/
They sell tanks. They say that steel tanks are cheapest. Then they go on to say, and I quote:

Fiberglass tanks are a rust-proof option in this age of ethanol fuels and biodiesel fuel products, offering some distinct advantages to traditional steel.

So, believe what you want about fiberglass motorcycle tanks.

View attachment 237357
I built the above bike in 2014. That's early Omar's glass. The tank was already several years old when I got it in 2014. I don't remember if there were any signs of it ever having gas in it when I got it. I used to have a pic of Kenny Roberts on an XS650 that had the same tank with the exact same graphics on it -- which I'm pretty sure were paint, not decals, if that's possible.
Anyways, at that time, 2014, Omar's said that the only tank liner that worked with fiberglass was Caswell. They would Caswell the tank that you were buying from them for a little extra. Yes, ethanol gas was everywhere in 2014.
So, I lined the tank with Caswell's. Used nothing but E10 in it. Never drained it. Rode it for a least year after I completed it. Sold it to a guy in south Texas. He'd call me every couple years to tell me how much he loved it. Never had any problems with the tank.

I've used Caswell many, many times since. It now comes in several colors, black, blue, grey, red, etc.
I've lined over failed Kreme liners more than once with no problems.
The only time I ever had a problem was when I made the mistake of measuring the proportions by weight instead of volume. It would not harden, but turned rubbery. I fixed it by re-lining with properly proportioned Caswell's. That was several years ago and the tank has been on my daily rider ever since.
By the way, I asked Caswell to give me the by-weight mixing proportions, and they didn't know what they were, a real shortcoming if you ask me. I mean, how hard can it be for them to figure it out? I have since calculated the by-weight proportions myself, not hard to do.

Final word: yes, E10 is nasty, but it's really nasty when it gets old. You need to keep cycling it, in other words you need to ride your bike enough that you're putting fresh gas in it like every three months or so at the most. If the gas is going to sit longer than that, I strongly recommend an ethanol fuel stabilizer. Which is a topic for a whole 'nother thread, and there are several on this Forum. The stabilizer I think is best is called "Ethanol Shield." It was little-known in 2014, but now Lowe's, Home Depot, and Walmart have it in-store.
Final final word -- I ride my bikes enough that I see no need for Ethanol Shield. But I ALWAYS used it in my Caswell's-lined Omar's tank, and I told the guy I sold it to to do the same.
Do you happen to recall what paint code yellow you used on that bike?

Looks very similar to Corvette Competition Yellow.
 
The glass was that way when I got it. The paint was extremely professional, and I always assumed it was done by or for Omar.
I chopped and painted the front fender using Valspar rattlecan # 85010 "Gloss Gold Abundance" from Lowe's, which was near-identical color.
 
@willis, have you had any resolution on this? I just went through the entire thread. Importantly, @willis did not apply the liner. So, there's no telling what could have gone wrong.

I have an XS750 tank on the shelf. I cleaned it to slick bare metal. I followed with 90 wt gear oil or fogging oil. It was many years ago, so I don't remember. What if I were to put a Caswell liner in it? What if I failed to remove 100% of the oil that I used to protect it? JAT.
 
@willis, have you had any resolution on this? I just went through the entire thread. Importantly, @willis did not apply the liner. So, there's no telling what could have gone wrong.

I have an XS750 tank on the shelf. I cleaned it to slick bare metal. I followed with 90 wt gear oil or fogging oil. It was many years ago, so I don't remember. What if I were to put a Caswell liner in it? What if I failed to remove 100% of the oil that I used to protect it? JAT.
Acetone will remove the oil. I'd do it more than once. Unless the outside of the tank has good paint. Then, I'd be extremely careful when I sloshed it.
I haven't followed up on either of my tank tumbling threads lately, but I finally tried tumbling with drywall screws. (They work just fine if you already have a bunch of them -- or roofing nails, or something -- and only have one tank to do, and don't want to spend money on HF abrasive media.) They work, but I thought they were too abrasive. They seemed to scratch up the good metal, removing a very small amount of it, rather than only attacking the rust. So, I think they'd be perfect for roughening your tank prior to the Caswell. Also, drywall screws are mentioned in the Caswell instructions.
 
Bit ironic that I link this source in this thread, but Marbles Motors mixes and sells the Yamaha Competition Yellow online; high quality PPG DBC stuff.

Why….whatever do you mean?
Old Men Laughing GIF by ABC Network


I know I’ve thrown a lot of hate at Marbles Motors in the past. But for what it’s worth I don’t think my experience was typical. I’ve moved on. 😎
 
Why….whatever do you mean?
Old Men Laughing GIF by ABC Network


I know I’ve thrown a lot of hate at Marbles Motors in the past. But for what it’s worth I don’t think my experience was typical. I’ve moved on. 😎
BTW, Randy has moved-on (sold, retired:shrug:). New guy (forget name atm) is very knowledgeable and provides excellent service.:twocents: He mixed and drop shipped all the Euro XS2 stuff to @Jim and if Dent is happy, well.......
 
Do you happen to recall what paint code yellow you used on that bike?

Looks very similar to Corvette Competition Yellow.
Not to harp on this semi-thread jack, but that pic I posted has way too much red in it, so I removed some of it. Compare the thumbnail pics below. The second pic is closer to the actual color.
Trophies.jpgTrophies2.jpg
 
@willis, have you had any resolution on this? I just went through the entire thread. Importantly, @willis did not apply the liner. So, there's no telling what could have gone wrong.
Unfortunately there has been no resolution. The bike was drained of gas and stored a year ago. I’m unsure quite how to proceed. Do I try a second application of Caswell over the failed portion, or do I just run it as is with good inline filters? Fortunately I have a few spare tanks I can substitute until a resolution can be made. I may address it once warmer weather arrives. Leaning towards tumbling with screws, cleaning and applying second Caswell coat. Aside from this failure, the rest of the epoxy is really nice and durable.
 
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