On Tue, 25 Jan 2011 15:05:06 +0000, Gary wrote:

As Petrol is taxed because it is used in cars ...

As "road fuel" otherwise the stuff burnt in motorcycles would be duty
free. B-)

You can get the duty back from HMR&C if you jump through the right
hoops.

Alternative *might* be ethanol, that is used in some countries
instead of petrol but not without problems.

--
Cheers
Dave.