Questioni have a 1981 virago and it failed emissions the hydrocarbons final reading is 2567 and its soppost to be 1800 or less can you help? and what is the spark plug gap for the 750 virago as well
AnswerMike,
-the emissions will be affected by
the general condition of the engine and
the state of tune.
-It may emit higher hydrocarbons
if you do not have stock pipes and air filters.
-Check your spark plugs and see if they
are clean,tan looking or black, black means
your fuel mixture is too rich or your compression
is low, it should be close to 150 psi.
-Your plugs should be NGK BP7ES, gapped at
.028"-.032"
-The air filter needs to be clean and make sure the
choke is fully off.
-The idle or pilot air screws should be about
2 turns out maximum.
-Check your fuel petcock valve vacuum lines for
any fuel, if there is fuel in the lines your
petcock or fuel valve on the tank will need
work. Sometimes they fail and start sucking
fuel into the engine which will definitely
cause it to fail emissions testing.
-it might help to change oil, add fresh fuel
and take it for a fast run before any testing
to clear out the engine and pipes of old
or heavy exhaust fumes.
-valve clearance is set about .004"-.005"
-ignition timing is not adjustable.
