The  T40R can mount onto virtually any sport or sport touring bike and has room for everything you'd need on a weekend trip. 

The Oxford T40R is the most sophisticated of seat bags, packed with useful and innovative features. Big enough to carry a full-face helmet when expanded, it is equally capable of swallowing up enough gear for a weekend away.

Features:

• 27L capacity (40L expanded) 
• Key pocket 
• Elasticated net for extra storage on top of the bag
• The bag can be unzipped from the base for quick removal
• 5 point secure fitting system: under-seat safety strap and 4 webbing straps
• Converts into a backpack
• 13.8" L x 14.2" W x 10.2" H (14.7" H expanded)