http://en.wikipedia.org/wiki/HandcarThe link above refers also to 'rail cycle with 4 wheels', which should satisfy most people, and 'three-wheel handcars'. By extension: '3-wheel rail cycle', '3-wheel rail bike' or 'rail tricycle'? / 'rail trike'?.
Seems you can mix and match the words to fit the technology you're trying to describe.
Although the technology is indeed a bicycle-type mechanism (a single in the case of a trike and a double bicycle in the case of the standard trolley for tourists) I prefer a phrase that uses the word 'cycle' because it's less specific. Besides, the pic below seems to show a trike without the front wheel, a kind of unicycle with stabilising outrigger wheel, which amounts to a bi-cycle if you really want to be picky.
http://www.notempire.com/images/uploads/Thumb...A Belgian company has also adopted the 'rail bike' mentioned earlier (www.railbike.be) .
The point to keep in mind is whether the context has been established in the text yet. 'Draisine' immediately conjures up the image of a thing on rails, so it can be used generically to establish context, without detail being required. The word 'trolley' is too broad and thus cannot establish context; it can only reflect or maintain it. A hundred years ago the automobile hijacked the word 'car', so we can't use that generically either. Even 'handcar' doesn't tell us much if we're not familiar with the things. Depending on the text I'd prefer to elaborate with 'a hand-pumped rail trolley' and then return to using 'handcar'.
Conversely, all other English phrases available to us, except 'railrider', are too detailed; they all specify either pedal or pump.
So 'railrider' or 'rail rider' it is, right?
Personally I wouldn't mind 'rail trolley', but they seem to be either full-scale wagons or more industrial contraptions e.g.
http://i93.photobucket.com/albums/l74/Thaitra...or
http://www.indiamart.com/sarsonenterprises/pc...or
http://lh6.ggpht.com/_jiddaqy8zA4/RzQdxXzkwbI...