Yeah, well, if you've got the walker locked into [surf/fly] / volt tackle you have roughly 10% chance to find either of them. Surf pika appears 3% of the time, fly pika 2%. So yeah, you need to like shake the pokewalker 40000+ steps per day if you're actually serious about it(which equates to about 2000 watts!) so....yeah. 3 or 2 % chance to get a surf/fly pika respectively isn't a lot. And LC EVing is a VERY long process, which is why I'm basically the only one on smogon who does it :/