Rubber rejuvenator ...?
 

Oooh errr missus ..... No, not that sort ... just aged, hardened rubber parts. In this case from the fuel line of a bike. It needs to be softened (as you can't get the part new anymore) so it'll work ... Any tips on softening it up?

Cheers

Dave

Is this of use: http://www.frost.co.uk/item_Detail.asp?productID=9004

Maybe something more appropiate here: http://www.frost.co.uk

You could try rubber and nylon lubricant, Halfords etc.
Forgotten make but I use it on doorseals etc.
Or a spray with silicone in like bumper restore stuff.
If it works clean excess off before refitting bits.
If the parts are washer type bits it's worth finding a local rubber supplier 'cos often they have lots of punches etc. to make washers. They usually have different thicknesses and types so tell them it's for petrol.
Worth finding a supplier as they can sometimes make something to suit.

I used to use glycerine on the rubber seals on some photographic/printing equipment. Just bought a bottle at Boots for 1.59 (labelled as cough medicine) to nourish the window seals on the Scoob :D