This is the perfect battery charger for the Yamaha FJ or FJR for a couple of main reasons.
 1. Its a CTEK (Yuasa sell these with their brand name on) Yuasa/GS have supplied ALL  GS and Yuasa O/E batteries for FJR1300 since the bike was introduced in 2001) so it  is recommended by the battery maker.
 2. This charger is actually sold (rebranded) by Yamaha so its recommended by Yamaha.
Its a 6 stage 12V smart charger and will charge any  lead acid type battery ( wet, MF,GEL, AGM Ca/Ca) between 1.2  and 32 Ah. It will not damage sensitive electronics and is spark proof with reverse polarity protection and is also short circuit proof.
Comes supplied with a permanent battery connection lead for quick connection and also a lead with crocodile clips.
Simple to use 
Just connect the charger to the battery and then connect the charger to a wall socket and switch on.
Charger will then charge battery fully automatically in 6 stages.