Next to each of your Google Calendars you will see a check box allowing you to select whether or not you wish to synchronise reminders for that calendar.

The following "rules" apply when synchronising alarms from different calendars:

Reminders active for your calendars
Reminders will be synchronised from both Google and the device.

Reminders turned off for your calendars
Reminders will not be synchronised from either Google or the device.
Reminders added or modified will be maintained during the sync process (e.g. reminders added to the device will not be added to Google but they will not be removed from the device).

Note - Reminders added to your device may not be added to Google if that particular calendar doesn't have any default reminder values set (under the Notification settings in Google Calendar).
Google have been making changes to how their reminders work and one of their changes is to allow the user how they wish to be notified when a reminder is available (via SMS, email or pop-up).
When the device sends a reminder it just sends the date and time of this reminder, unless Google is set to default to a particular notification type it will not be able to process the reminder time sent from the device.

Note - Due to restrictions in Google only the following reminder times can be sent from the device (if Google encounters an event with an unsupported alarm time that event will have its reminder removed before the event is added to Google Calendar):

• 5 minutes
• 10 minutes
• 15 minutes
• 20 minutes
• 25 minutes
• 30 minutes
• 45 minutes
• 1 hour
• 2 hours
• 3 hours
• 1 day
• 2 days
• 1 week