Use hydrogen, it's even lighter.  May make for an interesting ride as well.

Mike

On 4/25/03 9:05 PM, "John Rodgers" <j_rodgers@CHARTER.NET> wrote:

> pensioner wrote:
>
>>  Air has a large proportion of N2 in it as
>> shipped.  Now if it was He (helium) you might lighten your load
>>
> The lightened load from the extra lift would be short lived. The helium
> molecules are so small as to pass through the interstices in the rubber
> of the tyre, in the same way a childs ballon looses it lift when the
> helium leaks through the rubber walls.
>
> John Rodgers
> 88 GL Driver
>
>>
>>
>