Narrow gauge on trams tended to be used for the same reason as on trains.FleetlinePhil wrote: ↑Mon Aug 27, 2018 11:23 I'm not sure there were many places in the UK where physical constraints were the reason - I think it was more down to reducing costs. I recall reading that the tramway company was responsible for maintaining the roadway between the tracks and a certain distance either side, so this area would be reduced slightly with a narrower gauge. Some areas had company-operated trams throughout their lifetime, others were operated by the local council but even many of these had originally been built privately.
The tram tracks take up less of the roadway, allow tighter curves and as trams tend to run at lower speed high speed instability is rarely a problem. I think a major problem with re-introducing trams is likely to be noise. On tight turns steel wheels on steel rails do tend to make a lot of noise, a secondary issue is the relatively low level of friction between steel wheel and steel rail which limits rates of acceleration and braking. The noise issue is why some Paris Metro lines run on rubber tyres. The Quebec Metro uses rubber tyred vehicles only. Advice such as 'get good double glazing' is all very well but does not help on a warm humid night when you need to open the windows to sleep
I prefer a modern version of the trolley bus with a pantograph to pick up power and lithium ion batteries to allow it to cross dead spots and manoeuvre round collisions and incidents that would block traditional trams. Out of town you could run it as a guided busway such as the Cambridge system. The construction cost and disruption would also be greatly reduced.