I fitted a PC5454 (with a few simple 'mods') to my bike after the std battery got sick. I was away touring when it died, and couldn't push start the b*astard to fire it up, even with 2 big strong volunteers helping. The new battery has never even hesitated to fire up the motor. I figure riding a 1,5kg heavier bike is better than pushing a 1,5kg lighter bike a long way to find a steep hill to bump start it