Bicycle
32. The poskim forbade riding a bicycle on Shabbos even in a place with an eiruv, for multiple reasons. The main reason is because it is a weekday activity [עובדין דחול ] – “The way you go on Shabbos should not be like the way you go during the week” (גמ' שבת דף קי''ג ע''א ). A bicycle is mainly used to get to work or for sport (חוט שני ח''ג ס''ח ). There is also a concern that a person might mistakenly leave the techum Shabbos (כף החיים ). Also, perhaps there will be an issue with the bicycle, as is common, e.g., a puncture, flat tire, stuck chain, or the like, and the rider will fix it on Shabbos (שש''כ פט''ז אות י''ח ).
33. Muktzah. Therefore, regular bicycles are muktzah, with the status of a כלי שמלאכתו לאיסור (ארחות שבת פי''ט אות ס''ז ).
34. Children’s bicycle. Similarly, one should not allow children to ride children’s bicycles for the above reasons. A child should not even ride a bicycle with training wheels, as they are similar to regular bicycles.
35. Tricycle. A child may ride a children’s tricycle, as it does not at all resemble a regular bicycle, and the concerns with a regular bicycle do not apply to it.
Scooter
36. Riding a scooter is also a problem of עובדין דחול [even non-electric ones obviously]. Anyone over bar mitzva should not ride one. Children under bar mitzva should also not ride one.
37. Small children. Small children below chinuch age, e.g., until five years, do not need to be stopped from riding a scooter in another place, e.g., outside the house or in a courtyard, since scooters do not have the same concerns that regular bicycles do; for small children, they are like toys. However, they should not use them to get somewhere far, as then it is clear that it is a mode of travel and not a toy.
38. Skates. One should not use any sort of skates on Shabbos, e.g., Rollerblades, a skateboard, etc. This is a problem of עובדין דחול, as their main function is for sport, which is assur on Shabbos.
