(Portland, OR)  --  Portland's River View Cemetery is saying "no" to bicycle riders this Memorial Day weekend.  Director David Noble tells KGW-TV that signs have been installed near the cemetery entrances and exits to warn cyclists not to cut through between Friday morning and Monday night.  Noble says there have been a number of complaints about cyclists speeding through the cemetery, cutting off cars, and yelling and swearing at visitors.  He says Memorial Day is the busiest weekend of the year for the cemetery.