2007 Arctic Cat Y-12 90cc ATV Service Manual, Page 50Get this manual
37Install the cylinder head cover and secure with four cap screwsTighten to specifications DSC02295
33Install the spring, washer, and cap screw; then tighten to specifications
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38Inspect the transmission bearings and oil sealsReplace any worn or broken seals with new onesReplace any rough or worn bearings; then install the gasket and two alignment pins and press the drive gear into the bearing39Install the final drive gear, intermediate gear, and the final driven gear shaft into the left-side crankcase
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34Rotate the flywheel to align the "T" mark to the timing line on the right-side crankcase coverNOTE: Rotate the flywheel clockwise several revolutions to purge oil from camshaft lobes, tappets, and drive chain