As a start, make sure that you have the latest service packs installed.
Have you looked through the execution plan and query statistics?
This could be due to a number of issues such as blocking, resource contention, design issues or even index fragmentation and out of date statistics.
When you drop the view and re create it would be removed from the plan cache.
The next execution of the view would then put the plan into the cache again.
Do some digging and perhaps post some more information if you need further help