I don't have my own bike, so I want to buy a fixed gear bike.

我没有自己的自行车，所以我想买一辆单速车。

youdao

A fixed-gear bike is a bicycle whose pedals rotate at all times, even when coasting.

固定齿轮自行车是一种需要人一直不停地踩的自行车，即使在滑行时也要一直踩。

youdao

So if you see a bearded intruder on a fixed-gear bike in your neighbourhood, welcome him.

所以如果你在你住的社区看到一位骑着自行车、一脸络腮胡子的不速之客的话，就欢迎他吧。

youdao

And London-based architect Andy Martin teamed up with furniture company Thonet to design a gorgeous bentwood fixed-gear bike.

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On the other hand, the fixed-gear bike, currently popular with hipsters and cycling purists, is rather too Spartan, not to mention tough on the calves.

WSJ: An Urban Cyclist's Criteria

If you really want to get the most from your bike a smooth, reliable gear change is a must.

BBC: Sport