Hello,
First of all - if you have a responsive template (Bike Store is a responsive template) you shouldn't use the gkcache, because it is unnecessary. GK Cache was useful on non-responsive template where it adds a possibility of caching page for different devices.
As I remember in one of the latest template updates we have even removed this plugin from our quickstarts for responsive templates.
And yes - if you're using it, you should clean the cache manually.