Is 100kph enough as the maximum speed limit on our highways?

My arguments for increasing our speed limit (to even 120 or 140kph):

- most accidents do not occur due to high-speed driving, the last two SLEX accidents that I've heard occurred due to using the shoulder as the passing lane.

- speed limit should be classified per vehicle type. heck, almost all vehicles (even jeepneys) can run 100kph but can their vehicle handle it? IMO it should be like this:

cars from 1980 onwards: 120-140kph
cars below 1980: 100kph
buses, jeepneys and trucks: 80kph

- lane segregation should also be looked closely (as this has the biggest impact on traffic condition and road safety - NOT speed limit). ALL large vehicles should be relegated to the rightmost lane (as they block the view area of most vehicles - seen this working in singapore). slowpokes should also be shooed away from the passing lane.