Starting from 1st August 2016, full-sized bicycles will be banned from the Skytrain in Bangkok during peak hours. This announcement was inevitable. The skytrain carriages have been so crowded over the last few years that there has been little spare room for passengers, let alone bikes. I know some cyclists did their best to avoid rush hour and only use their carriage at the far end. However, some tour groups brought their customers onto the skytrain which obviously caused problems for everyone. One time I saw a group of eight cyclists in one carriage. Complaints about this kind of behaviour, and of course overcrowding, has led to to a ban. Though fortunately, it is not an outright ban like on the MRT Subway.
Starting from 1st August, you can only take full-sized bikes on the skytrain during these times:
Weekdays: 6:00 a.m. to 6:30 a.m. and 10:00 p.m. until close of service
Weekends: 6:00 a.m. to 9:00 a.m. and 10 p.m. until close of service.
This means you CANNOT take your bicycle on the train during the day between 6:30 a.m. and 10:00 p.m. on weekdays and between 9:00 a.m. and 10 p.m. at the weekend. However, folding bikes are allowed on the train at all times.