GS450 - Tires?

MY bike has 12 year old tires on it, not cracked but hard has rocks. I haven't had any close calls , but don't feel overly confident.

Suggestions? A few people said get battle axes, but I wasn't too sure. Also my tires are listed in measurements like 18x3.5 ... can't seem to find a calculator online to educate myself as to what I'm really looking for

Thanks!

j

Here's a conversion chart: http://www.webbikeworld.com/Motorcycle-tires/tire-data.htm

For a bike that old your choices of brand and model may be limited, I'd suggest going to dennis kirk or bike bandit to see what's available in your sizes.

Bought some Pirelli Sport Demons

100/90/18 120/90/18