When viewing your web site with a secure socket layer or SSL keep in mind that the data is being encrypted by your browser and then unencrypted by the server, this takes time. The higher the encryption the slower the process will take. This is why it is beneficial to use SSL for securing financial and sensitive information, rather then your entire site.
It is important that you encrypt credit card numbers and passwords, however it typically isn't important that your ‘special of the week’ or other sales information is secured for example.