If the tyres would not be round they will not move.
without air the tyres wont go round :/
Only round tyres can move smoothly while other shapes cannot.
Friction is desirable on your tyres and brakes. Tyres need to grip the road, to push the car forward, stop and go round corners. Brakes need friction to stop the wheels turning.
I'm guessing 1 of your tyres? It means it's out of shape, usually causes a vibration or wheel bearing type noise.
Front tyres 30psi Rear tyres 34ps1 Fully loaded 5 passengers with luggage Front tyres 30psi Rear tyres 38psi This is for Tyres 185/60/R15
how does friction help car tyres?
Assuming you're talking about the tyres... The tread on the tyres channels water away from the wheels - allowing the tyres to grip the road better than if the tyres were completely smooth.
because if the tyres are of metal the will slip
Normal pneumatic tyres do not work correctly without air. Run flat tyres do, so do solid tyres.
According to the manual for mine, it's 2 bar for the front wheels and 1.8 bar for the back. That is with a medium load and cold tyres. Should be 2.2 bar all round with a full load and you should add +0.3 bar when tyres are warm.
The advantages of using Continental tyres are that they are cheaper than some other tyres. Another advantage of using Continental tyres can be that they last longer than some other tyres.
There are many retailers and websites that can offer customers scooter tyres for sale. Some of these companies that offer scooter tyres are Scooter Tyre Store, My Tyres and National Bike Tyres.