sgd30-40 for gas per 2 weeks? depends on how you use but just to be safe alot about 100per month.
sportsbikes... (maintenance part)
2-stroke about sgd10-24 per litre which lasts about 2 weeks? so about 50-60 per month.
4-stroke, no idea...but suppose to be less costly...
cashcard depends on use so keep alert and monitor with care...
carry a booklet of coupons coz sometimes you'll be parking somewhere where there's no gantry..booklet about $6.50
outside parking check online, there're lists of free parking for motorcycles islandwide so quite convenient.. also plan your route, it'll save you time and gas money.
Hope this helps!