Talk:Speed

While narrow gauge such as 610mm saves on capital and running costs, the trade off is the low maximum speed which increases journey time.

For example on the 762mm gauge Victorian "Puffing Billing" railway which has 40m radius curves speed is limited to 24km/h (15mi/h).

It is not known what the maximum speed is allowed on straight track, which might also be limited by the strength of the track, considering:

spacing of sleepers;

weight of the rails;

the diameter of the driving wheels on the locomotives.