1999-2002 TRX400EX Fourtrax Service Manual, Page 114Get this manual
CYLINDERPISTON Spread each piston ring and remove it by lifting up at point opposite the gapCAUTION:
Do not damage the piston ring by spreading the ends too far
Clean carbon deposits from the pistonCAUTION Clean carbon deposits from the ring grooves with ring that will be discardedNever use wire brush; it will scratch the groove
INSPECTION
CYLINDER Inspectthe cylinder bore for scratch or wearMeasurethe cylinder 1.0at three levels in an and axisTake the maximum reading to determine the cylinder wearSERVICE LIMIT 85.10 mm 13.350 in) Calculatethe cylinder-to-piston clearanceReferto page 8-5 for measurement of the pistonO.DSERVICE LIMIT 0.10 mm (0.004in) Calculate the cylinder taper and out-of-round at three levels in an and axisTake the maximum reading to determine the taper and out-of roundSERVICE LIMITS Taper:0.05 mm (0.020 in) Out-of-round:0.05 mm 10.020 in) The cylinder must be rebored and an oversize piston fitted if the service limits are exceededThe 0.25 mm (0.010 in) and 0.50 mm (0.020 in) oversize pistons are availableThe cylinder must be rebored so that the clearance for an oversize piston is 0.0150.050 mm (0.00060.0020 in)TOP