This aluminum piston stopper screws in the spark plug hole. When the
piston is brought to contact with the stopper, you note the degrees on a
degree wheel, then turn the crank the other direction, mark the degree
point where it stops, and subtract the two points, to find true top dead
center. A dial indicator will do the same thing, perhaps more accurately,
but on some motors it is better to use a piston stopper. |
This
custom-built leakdown tester allows Moto Rapido to test seals, whether old
or new, for leaks. Leaky seals cause lean running in two-strokes, and
often allow engines to race out of control, causing seizures. |