Fuel tank expansion due to ethanol

[GuzziMoto]

Whatever the reason the tanks expand, the real issue is (in my opinion) that Guzzi did not make a tank that was suitable for its job. They knew ahead of time what would be put into the tanks, and yet they did not spec a tank made to properly hold said fuel and everything it would likely include.

Is it the end of the world? Not to me. I am used to having to finish building Guzzi motorcycles. Having to coat the inside of the fuel tank to make it capable of properly holding fuel is not that big a deal. Not to me. And I suspect many other Guzzi people feel the same way. I can, however, see how this could become a major shitstorm with other brands like Ducati. I can see those guys getting pretty upset that their uber expensive Italian exotic has a fuel tank that has issues if you put fuel in it.

[velofish]

Acerbis made the tanks.  I don't expect Guzzi to be expert on plastics.  The blame for this, if there is blame, rests on Acerbis and not on Guzzi, Ducati, MZ, Aprilia, etc

I wonder if it's helpful to run a ratchet strap circumferentially. around my tank when it's stored empty in my attic to help the shinkage?

Edited October 8, 2020 by velofish
correct autocorrect

[sunbeamtim]

Tank on the 2000 I just picked up had been off the bike for several years. It had stretched by 1/4 of an inch. just trimmed a little of the rear of the rubber tank mounts pushed it forward a little. Jim at hamlin cycles recommended draining the tank totally dry over the winter and refilling with non-ethanol fuel, and said it would shrink back. Fits and works fine at the moment. Will see if there are any other issues that appear.

[LowRyter]

9 hours ago, po18guy said:

Plastic contains chemicals which, by class, are known as plasticizers. They lend the flexibility and resilience to the base material. With heat and time, these plasticizers migrate out, through oxidation, heat cycles, sunlight (UV) or exosure to other chemicals and solvents. Thus old plastic of virtually all types becomes brittle. It usually shrinks, as its component parts leech out. But Guzzi tanks expand. That is from the chemical content of the gasoline  which they store. Ever clean rubber parts with alcohol? Some types will blow up like a balloon. Add that alcohol to gasoline and you get the same result.

That's predisposed with the notion that the tanks fitted right when they were installed new.   I have my doubts since it's plastic.  If it was caused by fuel, the why do some tanks fit well and others don't?  My guess it was because they were molded plastic and there was little consistency during the production process.

These companies have been using the ethanol excuse forever and there's still no proof.

[GuzziMoto]

4 hours ago, velofish said:

Acerbis made the tanks.  I don't expect Guzzi to be expert on plastics.  The blame for this, if there is blame, rests on Acerbis and not on Guzzi, Ducati, MZ, Aprilia, etc

I wonder if it's helpful to run a ratchet strap circumferentially. around my tank when it's stored empty in my attic to help the shinkage?

Fair enough, but Guzzi is the one paying Acerbis to make the tanks, they are spec'ing the tank. They are who we are buying the tank from, not Acerbis.

If I buy a Ford and something on it is poorly made I don't blame the vendor who made that part, I blame Ford. Not sure why Ford came to mind in my off the cuff example...

[EAB]

Hi guys, I run a store that specializes in a type of motorcycle that uses a plastic Acerbis tank and have the honor of owning other models with plastic tanks as well. After looking at the causes of deformation the only solution to the problem was to avoid gasoline with ethanol like the plague. Specially for storage or if you do not use your motorcycle often. The stuff is really harmful to the shape of plastic and wether it is because of the alcohol content in it or not, it really damages the tanks. I have a Ducati that was the cause of a lawsuit vs. Ducati and led to a recall and the free replacement of a tank. They replace it with a plastic tank by the way   - Subsequent models incorporated a metal tank for the US market. By the way, the majority of countries out there do not use Ethanol, its predominant in the US.  A Solution? : Metal tanks for the US market?

[Gmc28]

Mmmm, another ethanol thread. We are gluttons for punishment... :->

The tanks on my cagiva’s all fit fine from the dealer early on, so wasn’t an Italian QC issue. then over time they expanded and became very problematic. Same with other earlier model ducs from back when we had moved beyond metal but didn’t really see the effects of the ethanol yet.

As Phil and others have have indicated, clean em out, whichever way works best for you, then either coat the inside or or just convert to non ethanol gas. All my little gas powered stuff at home now, lawnmowers, weed whackers, dirt bikes, are all on clear gas, and none of them have the tank and carburation issues that plagued them before the ethanol issue was highlighted a number of years ago. Pretty dramatic difference on a large number of motors in my little sphere.

[bbolesaz]

This is a helpful resource for finding ethanol free gas.  Unfortunately, at least in Arizona, most of the ethanol free is not available at pumps, but rather in 5 gallon cans.

http://www.pure-gas.org

 

[docc]

48 minutes ago, bbolesaz said:

This is a helpful resource for finding ethanol free gas.  Unfortunately, at least in Arizona, most of the ethanol free is not available at pumps, but rather in 5 gallon cans.

http://www.pure-gas.org

 

Here in Tenn-o-see, that would be a generous quantity. After all, sometimes you want zero ethanol and sometimes: nuthin'-but . . .

[Gmc28]

2 hours ago, bbolesaz said:

This is a helpful resource for finding ethanol free gas.  Unfortunately, at least in Arizona, most of the ethanol free is not available at pumps, but rather in 5 gallon cans.

http://www.pure-gas.org

 

It’s a great one.  Like u say, hard to find in some places, but Then u end up in Montana and see it’s darn near everywhere (or was last time for me), and about the same price as regular.  Crazy.

[po18guy]

14 minutes ago, Gmc28 said:

It’s a great one.  Like u say, hard to find in some places, but Then u end up in Montana and see it’s darn near everywhere (or was last time for me), and about the same price as regular.  Crazy.

I called the customer service line at (Union) 76 petroleum and actually spoke with a person. She referred me to the puregas website, as their mix is different from state to state.

[Dan M]

I had this issue on both my LeMans and more so on an Aprilia Tuono. 

Draining the Aprilia tank and leaving it open (no filler cap or pump assembly) for a couple of months brought it back to original size. I coated it with Caswell's Dragon Blood sealer and it held it's size from then on. 

For some reason the expansion on the Lemans tank has not been as severe so I've left it alone.

[gkaan]

Has anyone experienced other symptoms associated with ethanol and tank damage / expansion?  I wonder if the ethanol causes a deformation of the exterior of the tank that is visible to the eye?  My silver tank has a minor crease near the point where it converges with the seat and side panel but it has no visible signs of exterior damage. Could this be due to years sitting in storage with ethanol fuel in the tank?  

 

 

 

[Lucky Phil]

2 hours ago, gkaan said:

Has anyone experienced other symptoms associated with ethanol and tank damage / expansion?  I wonder if the ethanol causes a deformation of the exterior of the tank that is visible to the eye?  My silver tank has a minor crease near the point where it converges with the seat and side panel but it has no visible signs of exterior damage. Could this be due to years sitting in storage with ethanol fuel in the tank?  

 

 

 

We need an image. The only visible external issues are reduced steering lock in some cases and bubbling paintwork. Maybe this "crease" is a form of that bubbling in the paint. But like I said an image would be helpful.

Ciao  

[jtucker]

I believe I'm experiencing some of that paint bubbling myself. On the bottom edge of the tank, above where the throttle bodies live. Only really noticeable when you're down low and looking up at the tank, so I haven't been too worried about it... yet. Looks like a bunch of small bumps, like a rash.

__Jason