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posted by The Bangkok Consultant
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They're not the most popular options with foreigners but many do use them. The ride can be a little hair-raising, but they are a good way of beating the rush hour traffic. It's not advisable to use one that does not have an orange jacket. These guys are regulated and have to at least have some kind of check to make sure their bikes are up to the job.
They're usually quite cheap, though avoid them at bus stations. If they're offering to take you somewhere for 300 baht, it's far too much. If it does seem too much then try to haggle.