Submitted by General (Delphi Forums Kawasaki Vulcan Forum)
Batterymart.com sells a vulcan vn2000 replacement for 79.95 that has 270 cca that is a replacement drop in for Vulcans (VN2000, Mean Streak, most Vulcans and Intruders as well as M109R Suzuki). I've bought two, one for the Mean Streak I totaled, it worked great, and one for my VN2000.
Buy that battery, and get proper charger that desulphates the battery and charges at 2 amps and your battery problems will be over. Trickle battery chargers sulphate your battery over time.
Here's the battery... YTX20CH-BS AGM Maintenance Free Battery
These guys are great.. they ship very fast. They have another web site called bigcrank.com. Same company - same products - same service.
Here's the charger... BatteryMINDer 12 Volt 2-4-8 Amp - it's made for agm and gel cell batteries - General