Conquer New Horizons with the Eastern Bikes Alpaka 29" Men's Hardtail Mountain Bike. Eastern Bikes Alpaka Hardtail Mountain Bike: $699. Buy Online Eastern Alpaka 29" Men's Mountain Hardtail Bike from Mountain-Bikes. The price of Eastern Bikes Alpaka Hardtail Mountain Bike is $699.99 with 5-star rating. Conquer New Horizons with the Eastern Bikes Alpaka 29" Mountain Men's Hardtail Bike. Aluminum Frame Ultra Light Hydroformed 6061, with 100mm Travel RST Suspension Fork, 9 Speeds, Front and Rear Hubs Sealed Bearing, 29"x 2.2 Kenda Tires, Warranty is 12months on all other parts, 5 years on Frame.