Setting Timing
Install a probe long enough to hit the top of the
piston in the end of the dial indicator. Mine is an early Kawasaki special tool
set and I have one set for Yamaha, which usually does the job for any and every
two stroke on the planet.
The dial indicator should have a shaft travel to be able to make the needle go
around at least 4 full rotations to be able to read the timing correctly for our
engines.
Now, for changing mm's into inches, as I have said previously, I set H1B's at
3.25mm BTDC. This would be .128 inch on the gauge, two complete rotations off
TDC, plus .028 on the gauge face. To get the right conversion from metric, as in
3.25, to thousandths, take the thousandths spec for one millimeter, and multiply
with the metric timing spec. .03936 x 3.25 = .12795, or round it off, .128. If
you wanted say, 2.94mm BTDC, like the later H1's use, then, .03936 x 2.94 =
.11718, or .117/.118.
So, with the gauge reading 0, piston all the way up in the bore, and the gauge
set so it can read piston movement downward in the bore, rotate the crank to the
right PAST the timing setting, two full rotations and .028, then reverse crank
and bring the piston up to the timing point, .128 BTDC. Set the pointer, mark
the rotor. When .128 is found, the gauge would read at 22 on the scale.
Install the dial indicator, turn crank until the gauge
doesn't move any more, and set the dial for 0, allowing for at least 4mm of
change in the gauge as the crank is turned off TDC.
Then, rotate the crank clockwise to move it BTDC, PAST the timing you want, say
to 3.50mm, then, reverse the crank and bring the piston up to the timing spec
you want to use, check/remark the timing line on the rotor for middle and right
cyls, move pointer for left cyl.
When you have that done, you can then dial each set of points in for the right
timing with the dwell meter and timing light. H1B has NO advance curve, so
where the light says, the timing is.
Indicate all 3 cyls, remark the rotor if need be, use
dwell meter/timing light to final set/check.
I use both a timing light and dwell meter to set the H1B ignitions.
Dwell meter: Set one set of points with the correct gap, then run the bike and
get a dwell reading, set the other two the same dwell for each cylinder. You
will actually be creating your own dwell meter reading to go by with the other
cylinders, so get the cap right. If I remember correctly, I use the 4 cyllinder
scale to get the dwell spec, but any reading/scale would be OK.
Now, with the dwell meter and timing light connected, set the timing on each set
of points, and confirm the dwell hasn't changed from the timing setting
operations. When done, the timing will be dead on for each cylinder, and the
dwells for all 3 will also be the same.
Just like using a Uni-syn to set carb balance,
dwell/timing is an active participation exercise, and you will have to go back
and forth setting the dwell and timing as you do each cylinder. What you want to
end up with is, same dwell, and timing on all 3 cylinders.
This is a rather time consuming thing, but to get it right, this is the way to
do it. Rebalance carbs with Uni-Syn, or better yet, mercury manometer (Carb Stix)
AFTER doing the timing.