In short, yes, they will slow you down and your productivity with it.
In my experience, the only thing you can do is try to motivate them (your coworkers) also. Even if you just accomplish to motivate 1 out of 50, it's a good job done.
Even though I'm not the best developer on the block, I do try to motivate others to do even better. I myself am visiting a lot of usergroups, when an interesting subject is presented I send a mail throughout the department and hope 1 or 2 will respond and come along. Most of the time they don't.
Also, try to write reviews/articles of things you have seen or learned and let the others know it. Most of the time I'm doing this stuff by mail because it's easy and everyone can read it when or if they want it.
Some mentoring is also a good idea. Even if you aren't the best developer on the block, you can probably still learn your coworkers a thing or two, or discuss about it.
Most of the time you won't succeed in motivating others though. They probably got different priorities and tell you they got a social life and you don't. Just disregard those remarks and go on with visiting, writing and try to motivate others. It's a hell of a job, but won't go unnoticed.