Question: Why do orthodox Jews refrain from riding bikes on the Sabbath?
Answer: Bicycles should not be ridden on Shabbat for three reasons:
- If the bike's chain falls off or the tire goes flat, one might repair the bicycle. ("Tzitz Eliezer" by R' E. Waldenberg, VII 30). Fixing the bike is like "making the bike anew", which is an act of creation. Jews refrain from creative activites on Shabbat.
- Bike riding is considered uvdin d'chol (a weekday activity). ("Code of Jewish Law" O.C. 327; MB 7).
- It is common to travel with a bicycle for a distance longer than the t'chum (Sabbath's 2000 cubit limit outside the city). To avoid going out of the t'chum, one should not travel with a bicycle on the Sabbath.
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