Plastic Fuel Tanks
 

I've been thinking about swapping the tank on my R1100GS to a plastic one for an African trip next year.
This is purely for weight reduction purposes.

I've often seen plastic tanks on pure off-roaders/scramblers/desert raiders but never on bigger tourers/dualies.

Any advice or thoughts?

Does it need a separate expansion tank or is a breather pipe/vent sufficient?
Does anybody produce these already - either off the shelf or to order?

The only reason to change for a plastic tank is for capacity. If you already have 200 + mile range then there's just no point. Any days you might need a bit more range, just strap on a container !

For those of us with tiny tanks on trailbikes (Mine has 10L), an Acerbis etc is pretty much essential for overlanding but I think your 1100 has a good 20 litres already.

Plastic tanks crash better than steel but I've not seen a pressed steel tank burst in anything but a MAJOR street crash. Even then, they are designed to bend rather than split.

A replacement for the 1100 is going to cost ££££££££££££££££££££ too. Money best spent elsewhere.

Thanks Tedmagnum

Do the plastic tanks have heavy wall thickness and therefore have no weight advantage?

How do plastic tanks cope with fuel vapour expansion?

Depends on the tank but I don't think they offer any genuine weight saving. They are pretty thick you see and are of a similar weight as the original.

As for vapor expansion, they usually adopt the same technology as trail bikes. The caps have either breather hoses or vented locks. Your GS will probably have a breather hose running under the tank.

Whats the range on your 1100 ?? Anything over 200 miles is just a bonus and for any long hauls, just strap on a plastic container and top your tank up when it will fit in.

I have twin Elkamet tanks on my F650 (aka wrongly as Touratech tanks as they sell them but they are made by Elkamet)

Both tanks have a venting pipe to the air. No vented locks or caps- Just good old fashioned tube open to the air-
IMHO, these are much tougher than OE tanks but no weight saving there
I took a dive at 60mph and the bike slid on both sides:rolleyes2: on the tanks- they got a bit like 'grated cheddar' where the rub was but did not puncture.
Aside from the added range the other benefits are one of convenience and more importantly their central location and proper weight balance -
and as for range...oh yes, a hair over 1000kms! The max I ever 'pushed' these were in Africa and 815Kms without finding any fuel!

In addition to the breather hose, most plastic tanks are permeable to petrol vapours, so it can also breath through the walls of the tanks. The downside of this is that you can't put any stickers on, and painting them is near impossible by simple means, as it'll throw bubbles and peel off eventually. On the other hand they neither rust nor get dents.

Just a little correction if I may Sirakor- as far as Elkamet tanks are concerned-
I was curious as I have Elkamet tanks- so I telephoned them today and put the question to their technicians-
The answer is: "no- our fuel tanks are not permeable to petrol vapour." Pffewwww, my HU stickers are safe after all! :Beach:

Thanks for that Bertrand - I should have added that this applies to Acerbis tanks!

Thanks for all the info guys.
Good stuff! :thumbup1: