Home Bike News Head to Head – BMW M135i vs BMW HP4 Bike News Head to Head – BMW M135i vs BMW HP4 By Nic Wang - January 20, 2015 563 0 Facebook Twitter Pinterest WhatsApp Vicki on a BMW M135i goes head-to-head with 2011 World Supersports Champion, Chaz Davies on a BMW HP4. Battling out in three challenges highlighting the key skills of each vehicle and reveals which is best!