I've done a lick over 28,000 in the last 12 months and about 11,000 so far this year.
If I don't ride a reasonable distance each week, I have withdrawals, but I have been running out of new roads.
As a guestimate, fuel at 8c per kilometre for fuel, that is $2240 for fuel, about $500 for tyres, $350 for service/oil etc., $550 insurance and reg. (single seat) equates to ~$3640 without considering depreciation and major repairs/upgrades.
~13c per Km.
~$70 per week.
I can't imagine (it fills me with almost a feeling of horror!) not having the bike, so it is well worth every cent.