The biggest problem facing the garden machinery service department these days is that of stale petrol. This causes poor starting, bad running, poor power, and damage to fuel system components. Normal unleaded petrol has a shelf life of only 30 days. A solution to this is to use Aspen fuel which will last for 5 years! Aspen 2-stroke and 4-stroke alkylate petrol is the cleanest form of petrol that is today available on the market.