Anyway, I don't think we can compare tire and fuel waste/consumption between US and Europe, Italy in particular.
The riding styles, the kind of roads and the traffic are completely different.
When I read US forums I see people stating that their tires last for more than 50.000 km (Harley Davidson), that in 50 years of riding they never had an accident or that bikes usually known for having "leaky tanks"
can pass the Sahara desert no stop for refuelling.
I keep reading this also on some Italian forums where you always meet someone swearing that his bike is capable of 40 km/litre...
If I obviously say "poor guy" to the Italian above because he clearly wants to show off or to be noticed anyway, I can almost believe to what is declared in US because:
- you (generally) ride bikes following cages rules with no accelerations, no quick overtakings, no lane splittings and respecting speed limits of even 25/30 mph or less
- most of you live and/or ride in immense spaces with long straights where a constant (low) speed (usually 55mph) is kept with the slightest use of the throttle: constant rpm's, no accelerations... for miles and miles!
- even in most of the cities, roads are large and straight and traffic flows well at a low speed; traffic lights and stop signals are present and this increases the gas waste but the driving style (for both cars and bikes) is not "nervous" but relaxed, thus accelrations are smooth and gradual with the least possible waste of gas
In Europe instead, and in Italy particularly, the style and the road conditions are completely different
- lot of curves, caotic traffic in cities where you have to be quick, thus accelerating much more
- less respect of speed limits when we are reasonably sure that there are no speed traps around
- bikes are perceived as a "fast" vehicle to avoid car traffic, slowings down and queues, thus almost all rules of driving a cage DO NOT apply: we pass where a car shouldn't, we split lanes, we "infiltrate" in a traffic jam (obviously we respect traffic lights and stops
)
Notice that the rules for cars apply exactly to bikes, but bikers risk more and police usually (not always unfortunately
) considers that breaking a road law for a bike helps to reduce in many cases the traffic jam
If you consider all this you can probably better agree that fuel and tyre wastes on this side of the pond are noticeably higher than those in the US.