I have a lithium battery in my bike but it is race only....The stock battery, the Yuasa YTZ7F(S) is 2.1kg (4.3lbs). 130CCA, 6AH, 113mm x 70mm x 105mm.
You can get a bunch of different Lithium batteries for the R7, the Dynavolt one weights 0.6kg (1.3lbs). So there's a weight saving of 1.5kg (3.3lbs) available if you want to run a lithium battery in your bike.
Other numbers for the battery (according to the Yuasa catalog) are:
SSB - RTX5L-BS
SSB (Lithium) - LFP5L-BS
Motobatt - MBTZ7S
Revplus - STZ7-S
Varta Powersport - VTZ7S
Dynavolt (Lithium) - MLFP7ZS