Plastic Tank problems: Discussion thread, see info thread sticky for updates

[krista]

PEX/XLPE actually allows fuel vapor to travel through it. This is why it can't be painted and why it's not CARB legal.

As I wrote above, we are going to fluorinate our MTT tanks upon production. This gives the outer layer of molecules a behaviour more like that of teflon with regard to vapor permissivity. From the research I have done, fluorination improves surface adhesion & will allow for the painting of PEX/XLPE.

- Chris

[hillbillypolack]

My second tank is twisting.  And, despite numerous emails to another alloy tank manufacturer I haven't received any replies.

This clusterbleep is making my bike unrideable.  I had wanted to be proactive in replacing the tank with alloy, so I am holding out hop for Iz's tank and heroic effort.

[jerryz]

So in reality as most bike manufacturers do ,,,STEEL is still king for fuel tanls ,of the majors  99% of bikes made use it  only Ducati and KTM seem to persist with plastics .

[Curmudgeon]

So in reality as most bike manufacturers do ,,,STEEL is still king for fuel tanls ,of the majors  99% of bikes made use it  only Ducati and KTM seem to persist with plastics .

Just out of curiosity, is the underseat tank on a BMW F-Series not plastic? BTW, my 851 had an nice alloy tank.

[twolanefun]

So in reality as most bike manufacturers do ,,,STEEL is still king for fuel tanls ,of the majors  99% of bikes made use it  only Ducati and KTM seem to persist with plastics .

There are models from many brands using plastic and affected by varying degrees including Aprilla, BMW, KTM, Moto Guzzi, MV Augusta, and yes even Harley Davidson. I give Ducati credit for new designs that enable them to hide the plastic fuel cell, such as the new monsters, pretty clever. But that does not give them a free ride on the remedy they offered for afffected bikes. - Gene

[muskrat]

I don't agree that hiding the problem is clever at all.  For the price of today's bikes they should have a solution IMO

[twolanefun]

Yeah you could be right. But along with those designs we also got huge increase between service intervals, reduced weight, DTC, ABS. And the price isn't bad. - Gene

[krista]

You guys keep forgetting about the costs with steel and alloy. There's a reason people use plastic: it's like 1/10th of the cost to get running. I'll be flatly stunned if anyone mass produces metal tanks for Ducatis. There is zero financial motive. The Big Four Japanese manufacturers sell enough numbers (like 100x Ducati) so the huge costs are amortized among more bikes. The metal tank Ducati made for the original Monster is probably why they kept using it until 2006 (last found on the S4R desmoquattro).

I'm quite amazed that over time, Ducatis have either kept the price the same or reduced. The original owner of the 1992 900SS I owned paid $10,500 for it. In 1991. What did a GSXR go for back then? $6k? The 888s were a bit over $20k.

If the fluorination proves to be the magic bullet for plastic tanks, we'll make another monster tank that mimics the factory tank's looks.

[twolanefun]

Agree and by not spending money on redoing the tanks in metal they added other features, bike was lighter, and the price was kept reasonable. In fact a M1100 EVO is a very competitive bike in the market. - Gene

[DRKWNG]

In fact a M1100 EVO is a very competitive bike in the market. - Gene

It's ugly too. 

[muskrat]

My Duc and my Harley have metal tanks and it's gonna stay that way.  They may cost more but I'm not buying the argument of incrementally shooting the price of the bike skyward.  Just look at the electronics and how much more time and effort went into that to be added. 

[twolanefun]

Hey I'm lucky enough to have the only Harley with a plastic tank. I got rid of the S2R but the XR1200 is not going anywhere. I just replaced the S2R1000, mostly my track bike, with another metal tank Duc, a nice find Supersport to be exact. - Gene

[NorDog]

Hey I'm lucky enough to have the only Harley with a plastic tank. I got rid of the S2R but the XR1200 is not going anywhere. I just replaced the S2R1000, mostly my track bike, with another metal tank Duc, a nice find Supersport to be exact. - Gene

The V-Rod has a plastic tank too.

[ducatiz]

The V-Wad has a plastic tank too.

fixed

[ducatiz]

PEX/XLPE actually allows fuel vapor to travel through it. This is why it can't be painted and why it's not CARB legal.

As I wrote above, we are going to fluorinate our MTT tanks upon production. This gives the outer layer of molecules a behaviour more like that of teflon with regard to vapor permissivity. From the research I have done, fluorination improves surface adhesion & will allow for the painting of PEX/XLPE.

- Chris

That's interesting.  EPA SHED testing shows XLPE gas tanks permeate at a lower rate than HDPE tanks.

EPA testing on Marine tanks made of HDPE and XLPE tanks showed XLPE rated lower permeation than all HDPE tanks. 

Plenty of HDPE tanks around on cars and boats.