It is important to be cautious in every neighborhood.
As a general rule, 18th Street is quite a safe street, I live on 17th, and walk up and down 18th all the time, mostly because of bi-rite, and dolores park. Also, there is a great dance studio, and climbing spaces nearby your location.
If you are an avid biker, the main thing is to just have a space to lock up your bike at night, or bring it into your new home. Any neighborhood has crime, and obviously it is important to be vigilant, but as a general rule, that is a very up and coming and young friendly area of the city.
Realtor Associate- BHG Mason McDuffie