The world’s top professional cyclists are riding toward the Tour de France finish line this weekend, and they’ll get there safer and cleaner than in previous years. Tramadol, a performance-enhancing opioid, has been banned from cycling at the request of riders themselves — an unlikely move in a sport marred by doping scandals. Tramadol is a common opioid painkiller used in the U.S. and across the world, and linked to peloton crashes in cycling. Since it isn’t banned by the World Anti-Doping Agency (WADA), athletes in high-intensity sports frequently abuse the drug to push past their pain threshold. But as the head doctor of the International Cycling Federation puts it, the evidence against the drug has been piling up for years.