Fiberglass tanks and todays fuel?

scott s

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I know that ethanol has wreaked havoc on 'glass tanks in the past, but at Barber this year I was talking to a vendor and she SWORE that their new resins and liners will stand up to todays fuels.
I can't remember with 100% certainty, but I think it was the Legendary Motorcycles booth (someone correct me if I'm wrong. They had a booth set up at the bottom of the steep hill in Aces Corner).

She even said old, unused tanks could be used with their liner. If it ever had gas in it, it must be THOROUGHLY cleaned, lined and even then they couldn't swear it would last, but she felt you had a good chance.

Anyway....current experience with 'glass tanks and ethanol laced fuel? I think we get about 10-15% ethanol around here.
What brand tank? How many miles? Any special precautions? I'd love to hear your experiences.
 
My 09 Aprilia came stock from the factory with one. Can't say I'm a fan. The factory finish looks like some 15 yr olds in a high school shop class had their hands on it. It also swells quite rapidly when I unbolt and lift the tank for any reason. Makes it a bitch to bolt back down. Other than that........beautiful........just fckin beautiful!
 
I had a fiberglass tank on a BMW caferacer. I tried whatever I could to preserve it, including 2 new coatings. It just dissolved.

I will never ever by a fiberglass tank again, I am convinced that it just doesn't work with modern fuel.

On the bright side: It gave me a reason to buy an aluminum tank.
 
scott s said:
I know that ethanol has wreaked havoc on 'glass tanks in the past, but at Barber this year I was talking to a vendor and she SWORE that their new resins and liners will stand up to todays fuels.
I can't remember with 100% certainty, but I think it was the Legendary Motorcycles booth (someone correct me if I'm wrong. They had a booth set up at the bottom of the steep hill in Aces Corner).

She even said old, unused tanks could be used with their liner. If it ever had gas in it, it must be THOROUGHLY cleaned, lined and even then they couldn't swear it would last, but she felt you had a good chance.

Anyway....current experience with 'glass tanks and ethanol laced fuel? I think we get about 10-15% ethanol around here.
What brand tank? How many miles? Any special precautions? I'd love to hear your experiences.

yeah, i was at barber too, saw their booth, did not talk to them, instead looked at the only tank of theirs i saw on a bike. it was pouring gas and had a rag stuffed up under it.

ethanol in gas has only been around a few years, not long enough to prove any technology on the road, I know any fiberglass tank made for pump gas before ethanol is useless now, and any tank promising to work hasn't had enough time to actually prove the technology with new fuel, if those tanks are still around after 10 years of use, I'd go ahead and buy one, but not now. if they're so sure of their tech and production quality, why not offer a warranty that refunds your money if the tank fails?

and another thing, people who professionally produce fiberglass are aware of not just the chemical compatibility of resins, but also the service temperature, a gas tank in service can reach very high temperature (don't think engine heat, think a black gas tank in florida while your bike is parked), resins have been around for a long time that will resist ethanol, namely those used for building underground gas tanks, but service temperature would never rise above 100f in those cases, so it's good to think of all the factors
 
miob said:
I had a fiberglass tank on a BMW caferacer. I tried whatever I could to preserve it, including 2 new coatings. It just dissolved.

I will never ever by a fiberglass tank again, I am convinced that it just doesn't work with modern fuel.

On the bright side: It gave me a reason to buy an aluminum tank.

I've been quietly buying up old beat up [ thus cheap ] alloy tanks for some time now. GUARANTEED Ethanol proof ! and so what if you have to repair / fill / paint.
 
In my trials bike with glass tanks, I have them lined and I drain them after every event. It's a pain but no issues so far...
 
We had ethanol blended gas in Washington state when I was in high school. Graduated in 1991, so, 22+ years ago. No problems with it even in early 70s era 'glass tanks, a proper cleaning, argon purge and then line with a USCG approved fuel tank coating. Some kind of flexible gunk than you dump in, rotate the tank enough times to build up a 1/16" thick layer. Looks like tool handle dip when it cures, but it stayed stable in ethanol blends.

Haven't looked for it in years so I don't remember the name. I do know we could only get it at the boatyards, your average boat supply is most likely not going to have it. And it takes forever and a day to cure, tanks had to be lined and left to cure while the rest of the bike was torn down and overhauled. Don't cure it in your workshop, attached garage or house, will get you higher than model cement...
 
The only thing I've ever personally used as a tank sealer is this stuff:


http://www.caswellplating.com/restoration-aids/epoxy-gas-tank-sealer.html


I've used it on steel tanks with great success 8) and I lined my vintage fibreglass Tracy with it, but have not tried fuel in that one as yet. :-\
 
I purchased a really nice looking Benji's Cafe Racers fiberglass tank, and they DO NOT come sealed for fuel use. The Caswell sealer was what was recommended for me to use to seal it. I followed the directions to a "T", and that stuff dried very hard.

After sitting with fuel for two weeks, I tried running the bike, and the carbs were choking. I looked in teh tank and found the sealer was blistering and pealing off in the tank. The guys at Caswell attributed this issue to regional fuel additives.

I was searching around on the internet to see if there was anybody out there in the fiberglass world that could salvage my beautiful looking tank, and I found Dave at Legendary Motorcycles. I was searching and I found a post Dave made on a Triumph forum about how fuel resistant his company's tanks were.

So I sent Dave my tank to have Legendary craft one of a similar size to fit my bike. The product I got back was simply amazing! It is so much cleaner than the Benji's tank, and LIGHTER! The interior of the Benji's tank is very rough, and there seems to be a lot of bondo and putty on the exterior. The Lengendary tank is smooth inside and outside. According to Dave, Legendary uses a vacuum bag on the tank halves to achieve this. So far, I have had fuel sitting in this tank for a couple of months, and I haven't had a single issue.

Here are some pictures of my tank being made...

Plug
foamtank1.jpg


Top half
image.jpg


Tunnel mold and top half trimmed up
twohalves_zpsa2a8a774.jpg


Tunnel and top being married together
joinedtank_zps87b45cf7.jpg


Finished tank
frontcups.jpg


tankbottom.jpg


IMAG0451.jpg


IMAG0454.jpg


IMAG0455.jpg
 
I've had no issues with my tank (built with West Systems Epoxy) after about 3-1/2 years with fuel in it. I sealed it with POR-15 after about a year due to some issues around the filler neck that I glassed in after priming with non fuel proof primer. The tank otherwise was showing no signs of deterioration even without the sealer.

CC
 
Ranger - thats freakin' sweet! Good to hear she's holding up well, and black is a traditionally very hard colour on glasses as well (why d'you think aeroplanes are white?) so its really the ultimate test.

Let us know if you have any problems, she looks very nice.

- boingk
 
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