Knobbly tyres

[Randochap]

There has been a trend to extremes over the last decade or more. First mountain bikes--which have never been any good on the road (excepting early prototypes, which can still be converted to decent commuters) and now that the road bike has come back into vogue, a lot of shops are pushing racing bikes onto unsuspecting people.

Fact is, most road cyclists would be better off with relatively wider tyres--up to around 40mm--with smooth rubber (next to no tread) and with supple casings. Most of this development (or rediscovery, if you will) is happening in the 650b size.

 

[jimboalee]

The secret of a free rolling bicycle is to have high pressure tyres.

The whole weight of the bike and rider is supported by the air pressure in the tyres. For example, a 200lb vehicle supported by two tyres ( with the weight evenly distributed ) will have 100lb resting on each tyre.
If the tyres are at 100 lb per square inch, there will be 1 square inch of rubber in contact with the road.

Bikes are usually 40/60 front/rear. This means 80 psi in the front and 120 psi in the rear.

The smoothest rolling bikes have 18 mm tyres at 130 / 170ish psi.


A 200 lb vehicle with 60 psi in both of its low pressure non-clincher tyres will be more difficult to roll.

This is why only the strongest cyclists ride 100 km Audax on Raleigh 20 shoppers.

 

[guitarpete247]

I've got an '88 Saracen Tufftrax and fitted these Schwalbe Landcruisers. I am finding them good both on and off road and at a reasonable price too. They're also p*nct*re proof (they say they are and I aint had a fairy visit yet).