[Tiger955iMan]

Hi - I've got a 2007 Tiger 955i and have blisters (air bubbles) on the tank decals - caused by leaving petrol in it over winter! I've contacted my local dealer who inform me it is the plastic tank breaking down, that there is no known cure and Triumph don't make the tanks anymore!! Does anyone have a suggestion for what I can do to remedy the situation?

I had intended to sell the bike this year but clearly can't pass this issue on to a new owner without curing it first.

 

[Steve Ford]

Have the decals replaced with paint.
The bad part is those bubbled decals are under the clear coat.

One enterprising soul cut away the clear coat, removed the decals and put on fresh vinyl ones. That would require a very steady hand, though.

Or there are these Bagster covers which some people like:

https://www.motolegends.com/bagster/bagster-tank-covers?Bike-Make=TRIUMPH&Bike-Model=TIGER-900-TIGER-955

 

[VABird]

Take a sewing pin and pop the blister at one of the thousands of dots.
Use your fingernail to work out the air.
Problem solved.

 

[Tiger-G]

I don't think it's got anything to do with leaving fuel in it over winter ??

My 2007 '955 is exactly the same, I don't worry about it. I did the old pin prick and work the air out, but they came back.

 

[lobout]

I've heard of this happening before pretty regularly. There have been a few posts on the subject. Doubt it's anything to do with petrol inside the tank.

 

[VABird]

I don't think it's got anything to do with leaving fuel in it over winter ??

My 2007 '955 is exactly the same, I don't worry about it. I did the old pin prick and work the air out, but they came back.

Agree. I had some blisters come back, but persistence pays. So far none have returned this summer.
Nothing to lose but a little blood if you jab your finger!

 

[Tiger955iMan]

Petrol Tank Blisters

Thanks to everyone for the replies.

I did the pin trick, although you can see the tiny holes if you look closely - will keep it up. Tank bags look good, may go for one of those to cover up my pin prick attempts!!!

 

[Lee337]

Most (if not all) plastic tanks suffer similar issues. its down to the Ethanol they put in fuel. Many years ago my Aprilia RSV tank was fine, until Ethanol was introduced in UK fuel. then the tank started to warp (as did my girlfriends Ducati Monster tank).

Fast forward to last year. My Tiger tank had the dreaded bubbles under the decals. My research suggested it was the Ethanol causing the problem. There is also evidence that it can also warp the tanks. If taken off the bike & left for a while, the bolt holes don't align the same as when it was taken off.

Since I got my Tiger last year, I've pricked the decals & 'massaged' the air out. I also only use premium fuel (BP or Shell) which until recently didn't contain Ethanol, at least in my geographical area. No returning bubbles.

Sadly, over the last 3 - 4 months, BP have started adding ethanol to their premium fuel. Bubbles are now back.

Ethanol hates plastic!

 

[Tiger-G]

Most (if not all) plastic tanks suffer similar issues. its down to the Ethanol they put in fuel. Many years ago my Aprilia RSV tank was fine, until Ethanol was introduced in UK fuel. then the tank started to warp (as did my girlfriends Ducati Monster tank).

Fast forward to last year. My Tiger tank had the dreaded bubbles under the decals. My research suggested it was the Ethanol causing the problem. There is also evidence that it can also warp the tanks. If taken off the bike & left for a while, the bolt holes don't align the same as when it was taken off.

Since I got my Tiger last year, I've pricked the decals & 'massaged' the air out. I also only use premium fuel (BP or Shell) which until recently didn't contain Ethanol, at least in my geographical area. No returning bubbles.

Sadly, over the last 3 - 4 months, BP have started adding ethanol to their premium fuel. Bubbles are now back.

Ethanol hates plastic!

Hi,

I don't see how ethanol, or any other components of fuel, can have an effect on external blisters ?? Is the ethanol seeping through the plastic tank from the inside on a molecular level ??

 

[Lee337]

Not sure of the exact process, but Ethanol is corrosive to both plastic and fibreglass to the point where it's use is banned in aviation due to safety concerns (although microlights are exempt).

Ducati were sued successfully in the USA in 2010 because of this issue, where the presence of ethanol rapidly caused their plastic tanks to degrade and deform.

Ethanol is also hygroscopic, so the higher the % of ethanol present, the more likely there is water getting into the fuel system.

This article may be of interest.

https://www.bmf.co.uk/news/show/will-ethanol-blended-fuel-damage-my-motorcycle

 

[Steve Ford]

All of the plastic tank models are going to have problems with the decals getting blisters.
It seems like sunlight helps to speed things up.
Not as bad as on the Buells, though, they had the paint itself bubbling along with the decals.

 

[revrandy]

Someone suggested to me to take a small needle, like diabetics use, puncture the blister, push out the air and then squeeze in a wee bit of superglue to seal the pin hole. This will stop water from getting underneath the vinyl and causing rust or rot down the road.

Anyone tried this? I have the bubbles as well, but haven't done anything about them.

 

[yakatak]

Ethanol eventually destroyed my tank. The paint was heavily blistered and gasoline started leaking around the battery tray studs. I repaired the leaks multiple times with various epoxy materials but none of them held for long. I was able to find a new tank in the right color and Caswell coated the inside. On year 5 with no signs of damage. I try to avoid use of ethanol but difficult on the road.

 

[Terry Colley]

This problem has been around for a while however issues with the surface finish and bubbling under decals is much less common than the distorting and swelling of tanks that has been occurring.

Acerbis is the main supplier and they manufacture street bike tanks out of nylon. The type of nylon they use, polyamide, has the unfortunate habit of being able to absorb water. And, as Lee337 has pointed out, ethanol is hygroscopic. It continuously absorbs water from the air which then leeches into the nylon of the tank causing it to distort and expand. I've seen tanks removed from Daytonas and Speed Triples for an afternoon of maintenance so distorted they can't be refitted because the mounting holes are 20mm out and no longer line up. HD even offer alternate trim kits for some of their models to cover up the large gaps that form between adjacent panels when the tank has expanded. The cure for this is to drain the tank and leave it in the sun. This drives the moisture out of the tank material quite quickly and it assumes it's correct form so fits again. Of course being in Australia this is easy, not so much in colder, damper climes.

Out of interest when you pinprick the blisters does any moisture come out?

Curiously, in over 18 years of 955 ownership, several models, I've never had a problem and I'm a habitual E10 user. Go figure.

 

[Tiger955iMan]

Hi everyone and thanks for your helpful comments. I've gone ahead with a reline of the tank with an ethanol proof product - £240. Feel relieved I've cured the problem and that the next owner won't get a nasty surprise.

 

[VABird]

My 955i has 45,000+ miles, is stored inside, and I usually run ethanol free gas.
There is a fuel treatment (Lucas ethanol treatment) I use when E-0 gas isn't available
I've had a few blisters, but worked them out with a needle. They haven't been back in about 2 years.
The tank has been off a number of times for maintenance, and always gone back on without the least distortion.