by dave#3 » Thu Nov 06, 2008 8:27 pm
Don't take this the wrong way, but have you ever owned a bike before? A zx10r's a hell of a bike to learn about what tyres look like when they're worn out on!
Tyres have wear indicators - blocks of rubber within the grooves - and when they're flush (or nearly flush) with the rest of the tyre the tyre is worn out. Tyres can wear out before that, however, such as if they're out of shape (squared off, scalloped out, edges worn out, etc) or simply because they've "gone off" (too much heat, too many heat cycles, old rubber, etc). For the most part it's a "feel" thing along with a visual inspection.
Life expectancy will vary by huge amounts based on a number of factors, but the OEM tyres on your 10 will probably be good for 4-7000 km's depending upon the rider and how they're maintained. Replacement costs can vary from $300 set to over $600, with average prices about $500 a set. Depending on what you buy these will last you from 2-20,000 kms.
Hope this helps.
dave#3 | '03 z1000 roadie | '08 zx6r tracky | '03 KLX400R dirty
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Winner - KSRC Murphy's Law Award 2008