Great motor, iffy electrics
V4 motor is a very robust design, with added reliability from the gear-driven cams. Oil and filter should be changed at least every 4000 miles (using a good quality, semi-synthetic oil); valve clearances every 16,000.The whine from the camdrive, incidentally, is perfectly normal and part of the NC’S character.
Tiny, exquisite and notoriously difficult to set up correctly, resulting in common mid-range flat-spots and the like from worn or badly adjusted carbs.those in bikes that have been standing for a while also often get clogged up with gunk and will require a full strip and clean.
If an import it will originally have been restricted to adhere to Japanese market regulations – although most by now will have been derestricted. Check the ignition unit under the seat (just ahead of the taillight). If it has a small black box plugged-in in sequence, it’s the gizmo (usually an M-max plug-in box) that overrides the 180kph/112mph speed restriction. It’s easier to remove the peg in the speedo.uk-spec VFR400S do not require derestricting.
A weak spot on most Hondas of the period and even genuine replacements rarely last more than five years.to check, use a multimeter across the battery terminals with the engine at 5000rpm – it should read a steady 14.4 volts. If significantly under, your best bet is a decent aftermarket item. Make sure you check the earth too.
All versions of thevfr suffer from weak electrics.a bad battery can easily take out your regulator and generator so check for charging/starting problems.the switchgear