Originally Posted by
aley
Because you're not used to the idea, and/or you're not picking your route well.
I avoid most arterial streets because the 40+ mph traffic and three lanes in each direction take most of the enjoyment out of cycling. In most cases you can find perfectly acceptable streets that are smaller, slower, and have less traffic, and it's a lot more comfortable for a newer cyclist to start taking the lane.
Be assertive, but avoid being a jackass about it. Make it clear that you belong on the road, and that you know you belong on the road, and you'll be surprised at how many drivers will simply accept your presence on the road.
Couldn't have said it better. I stay on streets I can stay up with traffic on. No need going on a 45 mph street. I stick to most side streets with way less traffic then the busy street next to it.
Also it does take some experience to get used to it. I was exactly the same when I would read people writing about taking the lane. After doing it for months it just becomes natural.