Hi and welcome to FixYa,
Most used 400s are ridden hard eitheras a starter bike or forced to max out playing catchup with biggerbikes. But unless abused, they tend to have longer usable life than thebigger ones. For a VFR400 (NC24), areas that would need your attention/check would be:
- was it imported to Australia by Honda or is it a gray bike? If it is a gray bike, then it would most likely be a Japanese domestic market/model that has a 180 km/h (110 mph) restriction;
- rear suspension - the NC24 was one of the first production bikes with Pro-Arm single-sided swingarm;
- listen closely to the "whine" sound from the engine. It should sound healthy not raspy. This is specially true for VFRs because the camshaft are driven by straight cut gears. This model does not use a timing chain or timing belt.
Common areas to check:
- condition/level of the engine oil. An oil change would do no harm;
- brake pads (front & rear);
- carbs and tank condition, A rebuilt/clean is a wise action;
- sparkplug check/replacement. Note the color/condition of the ends of the plugs;
- valve check/adjustment;
- electrical system check which includes battery/terminals, major connectors (high amperage), regulator, lights, switches;
- chain and sprocket. If adjusted against the stops, might be time for a replacement of the set;
- fork oil seal.
Even if there are somethingsyou feel like needing work, the general judge wold be how you likeriding the bike. Your body, sense of balance and riding style woulddictate which if ever would need priority work/replacement/checkingover.
Pls post back result(s). Good luck and Thank you for using FixYa.