Change tyres every two years ?? Shit, I was down to one rear tyre a month - and not quite two rear tyres for every front one .. I travelled just over 100 ks to work and killed a rear tyre in 3,001 ks - or just under 30 working days ...
You're all good changing just trhe rear - but make sure the new rear matches the front.
As has been said - the tryes are designed to work as a pair - and I prefer to keep them that way. I have mismatched tyres on my big Bandit - and I don't like them that much - the front is gripper than the rear (don't do it the other way around or the rear tyre will "push" the front tyre around) and occassionally the rear breaks lose under braking when it didn't used to when the tyres were matched ...
I'm going back to a matched pair when I need to replace them both ..
"So if you meet me, have some sympathy, have some courtesy, have some taste ..."
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