Piston Pin - Yamaha JT1 Series Service Manual

ENGINE-Cylinder, Piston Pin
C Cylinder Reconditioning
1) Pistons are available in 0.25 and 0.50 mm. (0.01
Q"
and 0.020") oversizes.
2) The cylinder should be rebored and honed to the diameter of the oversize piston plus the minimum allow-
able clearance
3) The error between the maximum and minimum diameters after honing should be no more than 0.04 mm.
(0.0015")
4) If cylinder rebore is necessary, be sure to chamfer all port edges to prevent the rings from catching
and breaking on o sharp port t::dge.
D Removing Carbon Deposits
Scrape off the carbon accumulation in the exhaust
port of the cylinder with the dulled end of a hack-
saw blade
E Installing the Cylinder
Put your fingers at each end of the piston ring.
expand the ring, and slip it onto the piston.Align
both ends of the ring with the knock pin m eac:h
rmg groove. Next. slip the cylinder down over
the piston. Compress the rings to prevent ring
breakage during installation.
3 -4 Piston Pin
A Pulling out the Piston Pin
Remove the clips at both ends of the piston pin
with needle nose pliers, and press out the piston pin
with a finger or a slot-head screwdriver.
Note : Before removing the piston pin clips, cover
the crankcase with a clean rag. so you will not
accidentally drop the clip or other foreign particles
into the crankcase.
Fig 3-3-3
Fig 3-3-4
Fig 3-4-1
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