With the FJs in hibernation I decided to fill their tanks (to prevent internal corrosion) and put in fuel stabilizer. The new bike won't be used until next April and I don't know when the old one will be back on the road. Advice varies on how long fuel lasts - seems 6 months is about the limit. The problem is that fuel oxidises and becomes gummy. I left half a tank in a bike for about 5 years and the tank above the fuel was heavily corroded and the fuel in the tap had turned to brown chewing gum. I've never had a problem with a bike stored without stabilizer over the winter but since the possible damage to carburettors is serious it seems like cheap insurance.