According to the Bombardier website, they are building a brand new Bombardier system in São Paolo. it is expected to cover approximately 24 kilometres, stopping at 15 intermediate stations, in approximately 50 minutes. Oh dear.
Show your calculations if you've got something better than that for your monorail.
Yeah, sure. That 50 minute time is pretty ridiculous, but I think I know why it's like that. There are about 3 possibilities: they're not running the system at full speed, the line has a lot of sharp corners, or they're using high dwell times for some reason. I think it's the last one, but I'll get to that in a second.
First of all, the alignment I've been looking at is https://mapsengine.google.com/map/edit?mid=zq16q5bIvtbA.kQFufhPzU0-g
. It requires knocking down a mere 3-5 houses or so. On a few occasions it would go over the top of some existing commercial development. Along most of it between Parramatta and Central, the only casualties will be parking spaces. Note that the only sharp corners that aren't near stations in that section are one just on the Newington side of Rosehill and two near North Strathfield. The stations are also fairly evenly spaced. This allows us to use the following rough calculations.
Approx length = 24km = 24000m
Stations between Parramatta and Central inclusive = 12
Average distance between stations = 24000 / 11 = 2181.8m
Accel/decel rate = 1m/s^2
Top speed = 80km/h = 22.2222...m/s
Time to reach top speed/stop from top speed = 22.2222...s
Displacement while accelerating/decelerating
= r_0 + (v + v_0)/2 * t
= 0 + 22.2222 / 2 * 22.2222
Total distance spent accelerating/decelerating between stations
= 246.91 * 2 = 493.83m
Distance at top speed between stations = 2181.8 - 493.83 = 1687.97m
Time to cover top speed distance = 1687.97 / 22.2222 = 75.96s
Total time between stations = 75.96 + (22.2222 * 2) = 120.4s
Total time excluding dwell = 120.4 * 11 = 1324.45s
Add 30s dwell time for each station = 1324.45 + 330 = 1654.45s = Approx 27 and a half minutes overall total.
Now this method tends to underestimate the total time by 1-2 minutes, so take that into account. Also, the distance by heavy rail between Parramatta and Central is actually only a touch over 23km, not 24km as used here. By the timetable current all stops services take 33 minutes, and express services take 26 minutes, so it should certainly work. It won't compete with a theoretical high speed express, but that would require tunnelling and would be much more expensive.
I've done these same calculations for a few existing metro/monorail systems as well, just to check that it was reasonably accurate. It comes out consistently 1-2 minutes under the correct total time for Copenhagen metro and Tokyo monorail (30s dwell time each), Osaka monorail (60s dwell time) and the Sao Paulo monorail (with a 90s dwell time). Admittedly this is assuming minimal sharp corners for all those systems, and the only one I can verify for that is Copenhagen, but I think that's a fairly safe assumption.
So going by all this, I expect that the monorail in Sao Paulo has a 90 second dwell time for some reason. I have no idea why, but there you go. That sort of time is also pretty consistent with several of the other metro lines they have there, so it's plausible.
points for guessing which station pair I'm referring to...
No idea. I can find a number of station pairs that take 7 minutes to traverse, but the longest of those seem to be 9-10km apart (eg Moss Vale and Bowral). But this is going by the current timetable, and you may not be.
Edit: Link fixed. I swear, BBCode is broken here.